Search Results: "eof"

8 April 2023

Evgeni Golov: Running autopkgtest with Docker inside Docker

While I am not the biggest fan of Docker, I must admit it has quite some reach across various service providers and can often be seen as an API for running things in isolated environments. One such service provider is GitHub when it comes to their Actions service. I have no idea what isolation technology GitHub uses on the outside of Actions, but inside you just get an Ubuntu system and can run whatever you want via Docker as that comes pre-installed and pre-configured. This especially means you can run things inside vanilla Debian containers, that are free from any GitHub or Canonical modifications one might not want ;-) So, if you want to run, say, lintian from sid, you can define a job to do so:
  lintian:
    runs-on: ubuntu-latest
    container: debian:sid
    steps:
      - [ do something to get a package to run lintian on ]
      - run: apt-get update
      - run: apt-get install -y --no-install-recommends lintian
      - run: lintian --info --display-info *.changes
This will run on Ubuntu (latest right now means 22.04 for GitHub), but then use Docker to run the debian:sid container and execute all further steps inside it. Pretty short and straight forward, right? Now lintian does static analysis of the package, it doesn't need to install it. What if we want to run autopkgtest that performs tests on an actually installed package? autopkgtest comes with various "virt servers", which are providing isolation of the testbed, so that it does not interfere with the host system. The simplest available virt server, autopkgtest-virt-null doesn't actually provide any isolation, as it runs things directly on the host system. This might seem fine when executed inside an ephemeral container in an CI environment, but it also means that multiple tests have the potential to influence each other as there is no way to revert the testbed to a clean state. For that, there are other, "real", virt servers available: chroot, lxc, qemu, docker and many more. They all have one in common: to use them, one needs to somehow provide an "image" (a prepared chroot, a tarball of a chroot, a vm disk, a container, , you get it) to operate on and most either bring a tool to create such an "image" or rely on a "registry" (online repository) to provide them. Most users of autopkgtest on GitHub (that I could find with their terrible search) are using either the null or the lxd virt servers. Probably because these are dead simple to set up (null) or the most "native" (lxd) in the Ubuntu environment. As I wanted to execute multiple tests that for sure would interfere with each other, the null virt server was out of the discussion pretty quickly. The lxd one also felt odd, as that meant I'd need to set up lxd (can be done in a few commands, but still) and it would need to download stuff from Canonical, incurring costs (which I couldn't care less about) and taking time which I do care about!). Enter autopkgtest-virt-docker, which recently was added to autopkgtest! No need to set things up, as GitHub already did all the Docker setup for me, and almost no waiting time to download the containers, as GitHub does heavy caching of stuff coming from Docker Hub (or at least it feels like that). The only drawback? It was added in autopkgtest 5.23, which Ubuntu 22.04 doesn't have. "We need to go deeper" and run autopkgtest from a sid container! With this idea, our current job definition would look like this:
  autopkgtest:
    runs-on: ubuntu-latest
    container: debian:sid
    steps:
      - [ do something to get a package to run autopkgtest on ]
      - run: apt-get update
      - run: apt-get install -y --no-install-recommends autopkgtest autodep8 docker.io
      - run: autopkgtest *.changes --setup-commands="apt-get update" -- docker debian:sid
(--setup-commands="apt-get update" is needed as the container comes with an empty apt cache and wouldn't be able to find dependencies of the tested package) However, this will fail:
# autopkgtest *.changes --setup-commands="apt-get update" -- docker debian:sid
autopkgtest [10:20:54]: starting date and time: 2023-04-07 10:20:54+0000
autopkgtest [10:20:54]: version 5.28
autopkgtest [10:20:54]: host a82a11789c0d; command line:
  /usr/bin/autopkgtest bley_2.0.0-1_amd64.changes '--setup-commands=apt-get update' -- docker debian:sid
Unexpected error:
Traceback (most recent call last):
  File "/usr/share/autopkgtest/lib/VirtSubproc.py", line 829, in mainloop
    command()
  File "/usr/share/autopkgtest/lib/VirtSubproc.py", line 758, in command
    r = f(c, ce)
        ^^^^^^^^
  File "/usr/share/autopkgtest/lib/VirtSubproc.py", line 692, in cmd_copydown
    copyupdown(c, ce, False)
  File "/usr/share/autopkgtest/lib/VirtSubproc.py", line 580, in copyupdown
    copyupdown_internal(ce[0], c[1:], upp)
  File "/usr/share/autopkgtest/lib/VirtSubproc.py", line 607, in copyupdown_internal
    copydown_shareddir(sd[0], sd[1], dirsp, downtmp_host)
  File "/usr/share/autopkgtest/lib/VirtSubproc.py", line 562, in copydown_shareddir
    shutil.copy(host, host_tmp)
  File "/usr/lib/python3.11/shutil.py", line 419, in copy
    copyfile(src, dst, follow_symlinks=follow_symlinks)
  File "/usr/lib/python3.11/shutil.py", line 258, in copyfile
    with open(dst, 'wb') as fdst:
         ^^^^^^^^^^^^^^^
FileNotFoundError: [Errno 2] No such file or directory: '/tmp/autopkgtest-virt-docker.shared.kn7n9ioe/downtmp/wrapper.sh'
autopkgtest [10:21:07]: ERROR: testbed failure: unexpected eof from the testbed
Running the same thing locally of course works, so there has to be something special about the setup at GitHub. But what?! A bit of digging revealed that autopkgtest-virt-docker tries to use a shared directory (using Dockers --volume) to exchange things with the testbed (for the downtmp-host capability). As my autopkgtest is running inside a container itself, nothing it tells the Docker deamon to mount will be actually visible to it. In retrospect this makes total sense and autopkgtest-virt-docker has a switch to "fix" the issue: --remote as the Docker deamon is technically remote when viewed from the place autopkgtest runs at. I'd argue this is not a bug in autopkgtest(-virt-docker), as the situation is actually cared for. There is even some auto-detection of "remote" daemons in the code, but that doesn't "know" how to detect the case where the daemon socket is mounted (vs being set as an environment variable). I've opened an MR (assume remote docker when running inside docker) which should detect the case of running inside a Docker container which kind of implies the daemon is remote. Not sure the patch will be accepted (it is a band-aid after all), but in the meantime I am quite happy with using --remote and so could you ;-)

1 April 2023

Paul Wise: FLOSS Activities March 2023

Focus This month I didn't have any particular focus. I just worked on issues in my info bubble.

Changes

Issues

Review

Administration
  • Debian QA services: disabled updating jessie as it was removed
  • Debian IRC: rescued #debian-s390x from inactive person
  • Debian servers: repair a /etc git repo
  • Debian wiki: unblock IP addresses, approve accounts

Communication
  • Respond to queries from Debian users and contributors on the mailing lists and IRC

Sponsors The gensim, sptag, purple-discord, harmony work was sponsored. All other work was done on a volunteer basis.

28 March 2023

Matt Brown: Ventilation Monitoring: Ensuring every space has clean, fresh air

The importance of clean, fresh indoor air is one of the most tangible takeaways of the Covid-19 pandemic. In addition to being an effective risk mitigation strategy for reducing the spread of respiratory illnesses, clean, fresh air is necessary to enable effective cognitive performance. Monitoring indoor air quality is relatively easy to do, but traditionally has not been a key focus. I believe air quality monitoring should be accessible for any indoor space, and for highly occupied indoor spaces should be provided on a continuous basis. This post explores the need and an opportunity for a business that can accelerate the adoption of ventilation monitoring through the following topics:

The importance of indoor air quality Clean, fresh air is fundamental to life and health. That might sound obvious, but unfortunately being obvious is not enough to ensure the air we breathe is in fact always clean and healthy. Repeated studies have revealed that in many cases the air you re breathing at school, in the bus or at work and probably also at home falls well below the ideal of what clean, fresh air should be. Unclean air has potential long-term health impacts and has also been shown to lower cognitive performance impacting the ability to learn and work as well as increasing the risk of transmission of respiratory illnesses like Covid-19 and the flu. Ventilation (replacing old stale air with clean fresh air) is the most effective and economical method of improving and maintaining high indoor air quality. Most New Zealand buildings (including schools and houses) are designed to rely on manual ventilation (opening windows), while newer buildings, often including larger or commercial buildings may use mechanical ventilation involving fans and ducts. Mechanical ventilation including filtration may also be required in situations where the outdoor air is not clean and fresh such as in a city or next to a busy intersection.

Observing the invisible Overall air quality is a complex topic involving many contributing factors, many of which are invisible and not perceptible to us until well after adverse effects or irritation occur. This complexity and lack of visible signal is a large contributing factor to the ignorance and lack of attention towards indoor air quality that is prevalent in most buildings and indoor spaces today. Our attention is biased towards the risks that we can see, and this default bias has not been helped by hesitation and resistance to the idea that aerosol transmission and air quality is an important factor in preventing disease transmission that has only recently started to change. Zeynep Tufekci has a great overview that provides fascinating context for how an overreaction to the early incorrect theories of bad air and miasma causing disease contributed to aerosol transmission and air quality being incorrectly neglected for so long. Correcting this history of inattention to indoor air quality is going to take time and effort, but one significant step that we can take to help start the journey to ensuring all indoor spaces have clean, healthy air is to make the invisible part visible. The concentration of carbon dioxide (CO2) in a space is an incredibly effective and easy to measure proxy for the ventilation of a space. The atmospheric background level of CO2 is around 420 parts per million (ppm), while our exhaled breath has concentrations as high as 40,000 ppm. Without effective ventilation, one or more people breathing in an enclosed space will rapidly lead to an observable increase in CO2 concentration, which in turn provides a signal that the ventilation is insufficient and needs to be improved. Monitoring CO2 and improving ventilation is not a panacea for all possible air quality issues, but for the majority of buildings and indoor spaces, using CO2 as a proxy for ventilation and increasing ventilation when CO2 levels rise above recommended levels is a simple, effective and achievable approach that will deliver improvements in cognitive performance and reduction in the risk of disease transmission with few, if any, downsides or risks. See this Public Health Communication Centre briefing for a more detailed explanation.

Adding clean air to our hygiene practices We have well established expectations of hygiene for the food we eat and the water we drink and these expectations are codified in regulations that ensure those providing these services do so in a way that gives us confidence that we re not going to be at risk of illness. You may recall seeing food grade ratings prominently displayed on the walls of restaurants and cafes that you visit as an example of this. Why should the air we breathe be treated any differently? I think there is a strong argument that indoor air quality deserves regulation, both of the absolute quality of the air and ensuring that the practices and achieved air quality are clearly advertised and available. Ventilation monitoring via measurement of CO2 concentration provides an effective and achievable method that can be used to achieve this, and countries like Belgium and Japan are already starting to regulate indoor air quality. In the UK, the independent SAGE group of scientists has published Scores on the Doors , a proposal which demonstrates how CO2 monitoring can be helpful in providing information about the air quality of indoor spaces. Unfortunately there is no movement in any of these directions in New Zealand yet, and no sign that regulation or even a basic campaign to raise awareness of ventilation and air quality is even being planned. This is disappointing, but even if such work was planned, it would still require appropriate ventilation monitoring products and services to enable it, and while there are some options available, it is not a fully solved space yet.

Existing ventilation monitoring options Until recently the available offerings for ventilation monitoring have sat at two distinct ends of the price and quality spectrum:
  • Handheld air quality meters advertised as measuring CO2, but in reality reporting only an approximation. These meters do not contain actual CO2 sensors, and only approximate CO2 levels based on measurements of other components of the air. While cheap (often less than $100), these meters are not useful for providing reliable data that can be systematically used to assess and improve ventilation and should be avoided.
  • High-end building management systems (BMS), and industrial measurement products targeted at large buildings such as offices or commercial applications such as food production. These systems require specialist installation, often integrated with large whole-building air conditioning systems. These systems, if appropriately configured, can be a great solution for the types of buildings and spaces that can afford them, but by their nature and cost, they do not offer a solution for the majority of smaller buildings and indoor spaces where we tend to spend a lot of our time.
Over the last few years a growing number of companies have developed products that fit in between the unreliable air quality meters and the expensive BMS/industrial measurement products. Promising NZ-based options in this space include Air Suite, Tether and Monkeytronics. These products are wall mountable, resemble a smoke alarm and utilise a WiFi network to report their measurements to a supporting web service. Pricing varies between $200 and $300 ex GST per unit. Aranet, while not NZ based, provides a handheld monitor the Aranet4 Home, which is well regarded for quality and accuracy. Aranet4 Home devices are the most expensive in this space, retailing at $386 ex GST and offer a clunkier and less convenient set of connectivity options via a Bluetooth connection to an associated phone. To obtain similar reporting functionality to the other products requires upgrading to their Pro model and purchasing a separate base station at a combined cost of $1255 ex GST. Outside the commercial product offerings are a number of open source DIY options, which can be built by anyone with basic electronics knowledge. AirGradient is a leading example based in Thailand, and within New Zealand Oliver Seiler s CO2 Monitor provides similar functionality. These open source options have a parts cost in the $100-$150 range, depending on volume built and provide high-quality measurements via trusted CO2 sensors while also offering huge flexibility in terms of how they operate, interact with users and potential supporting web services.

An opportunity: Small businesses and organisations While a growing number of high-quality CO2 monitors has the potential to help drive increased adoption of ventilation monitoring, the plethora of small businesses and organisations that own, operate and manage many of the indoor spaces we visit on a day-to-day basis do not appear to be well served by these existing products. To deploy ventilation monitoring a small business or organisation needs to first become aware of the need or demand for it, and then have a simple and easy path to acquire and install the monitor and access the data. Little to no marketing or demand generation appears to be targeted towards this market from the existing businesses and tellingly, several of the products are not directly available for sale, requiring interaction with a salesperson to purchase. This indicates a focus on selling to larger customers who have a campus or portfolio of buildings and will purchase in larger quantities than the typical small business or organisation will. Small businesses and organisations are likely to occupy smaller buildings and spaces where manual ventilation is the prevalent method of improving and maintaining air quality. Maintaining clean, fresh air via manual ventilation requires the occupants of the space to receive an obvious and straightforward signal when action (opening windows, etc) is required. While the products above all tend to provide some form of local feedback and display in the room, the indication provided and notification of when to take action is less obvious and prominent than would be ideal in a situation where manual ventilation is being relied upon. Informally testing this opportunity with family and friends running small businesses over the last few months has resulted in promising feedback. One particular success story was the discovery of a fresh air duct on the air conditioning unit in a small office that had never been connected to the outside air and was simply recirculating air from the ceiling space back into an office! The resulting stuffiness and poor air quality had been noticed, but without the clear indication from the CO2 monitor that the air conditioning was actually making things worse, rather than better, the underlying issue had not been understood. With the issue fixed and the duct now connected, that business is now enjoying much more productive and healthy working conditions.

Next steps Many small businesses and organisations are likely to have poor air quality and opportunities for improvement similar to the example above that are waiting to be found and fixed, and the existing products available are neither focused or ideal for the needs of this market. I have spent some time over the past six months building a basic CO2 monitoring service that I have used to deploy ventilation monitoring to our local school, and a few other local businesses. There are a number of challenges that still need to be addressed in order to scale the business up, but I think there is a reasonable chance that I can build a viable business that offers an attractive and useful solution that would accelerate the deployment of ventilation monitoring for small businesses and organisations. In an upcoming post, I will explain the foundations of the service that I have built to date, the challenges that need to be overcome and how I plan to evolve the service from the current prototype into a sustainable, bootstrapped business.

kpcyrd: Writing a Linux executable from scratch with x86_64-unknown-none and Rust

I recently mentioned on the internet I did work in this direction and a friend of mine asked me to write a blogpost on this. I didn t blog for a long time (keeping all the goodness for myself hehe), so here we go. To set the scene, let s assume we want to make an exectuable binary for x86_64 Linux that s supposed to be extremely portable. It should work on both Debian and Arch Linux. It should work on systems without glibc like Alpine Linux. It should even work in a FROM scratch Docker container. In a more serious setting you would statically link musl-libc with your Rust program, but today we re in a silly-goofy mood so we re going to try to make this work without a libc. And we re also going to use Rust for this, more specifically the stable release channel of Rust, so this blog post won t use any nightly-only features that might still change/break. If you re using a Rust 1.0 version that was recent at the time of writing or later (>= 1.68.0 according to my computer), you should be able to try this at home just fine . This tutorial assumes you have no prior programming experience in any programming language, but it s going to involve some x86_64 assembly. If you already know what a syscall is, you ll be just fine. If this is your first exposure to programming you might still be able to follow along, but it might be a wild ride. If you haven t already, install rustup (possibly also available in your package manager, who knows?)
# when asked, press enter to confirm default settings
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs   sh
This is going to install everything you need to use Rust on Linux (this tutorial assumes you re following along on Linux btw). Usually it s still using a system linker (by calling the cc binary, and errors out if none is present), but instead we re going to use rustup to install an additional target:
rustup target add x86_64-unknown-none
I don t know if/how this is made available by Linux distributions, so I recommend following along with rust installed from rustup. Anyway, we re creating a new project with cargo, this creates a new directory that we can then change into (you might ve done this before):
cargo new hack-the-planet
cd hack-the-planet
There s going to be a file named Cargo.toml, we don t need to make any changes there, but the one that was auto-generated for me at the time of writing looks like this:
[package]
name = "hack-the-planet"
version = "0.1.0"
edition = "2021"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]
There s a second file named src/main.rs, it s going to contain some pre-generated hello world, but we re going to delete it and create a new, empty file:
rm src/main.rs
touch src/main.rs
Alrighty, leaving this file empty is not valid but we re going to walk through the individual steps so we re going to try to build with an empty file first. At this point I would like to credit this chapter of a fasterthanli.me series and a blogpost by Philipp Oppermann, this tutorial is merely an 2023 update and makes it work with stable Rust. Let s run the build:
$ cargo build --release --target x86_64-unknown-none
   Compiling hack-the-planet v0.1.0 (/hack-the-planet)
error[E0463]: can't find crate for  std 
   
  = note: the  x86_64-unknown-none  target may not support the standard library
  = note:  std  is required by  hack_the_planet  because it does not declare  #![no_std] 
error[E0601]:  main  function not found in crate  hack_the_planet 
   
  = note: consider adding a  main  function to  src/main.rs 
Some errors have detailed explanations: E0463, E0601.
For more information about an error, try  rustc --explain E0463 .
error: could not compile  hack-the-planet  due to 2 previous errors
Since this doesn t use a libc (oh right, I forgot to mention this up to this point actually), this also means there s no std standard library. Usually the standard library of Rust still uses the system libc to do syscalls, but since we specify our libc as none this means std won t be available (use std::fs::rename won t work). There are still other functions we can use and import, for example there s core that s effectively a second standard library, but much smaller. To opt-out of the std standard library, we can put #![no_std] into src/main.rs:
#![no_std]
Running the build again:
$ cargo build --release --target x86_64-unknown-none
   Compiling hack-the-planet v0.1.0 (/hack-the-planet)
error[E0601]:  main  function not found in crate  hack_the_planet 
 --> src/main.rs:1:11
   
1   #![no_std]
              ^ consider adding a  main  function to  src/main.rs 
For more information about this error, try  rustc --explain E0601 .
error: could not compile  hack-the-planet  due to previous error
Rust noticed we didn t define a main function and suggest we add one. This isn t what we want though so we ll politely decline and inform Rust we don t have a main and it shouldn t attempt to call it. We re adding #![no_main] to our file and src/main.rs now looks like this:
#![no_std]
#![no_main]
Running the build again:
$ cargo build
   Compiling hack-the-planet v0.1.0 (/hack-the-planet)
error:  #[panic_handler]  function required, but not found
error: language item required, but not found:  eh_personality 
   
  = note: this can occur when a binary crate with  #![no_std]  is compiled for a target where  eh_personality  is defined in the standard library
  = help: you may be able to compile for a target that doesn't need  eh_personality , specify a target with  --target  or in  .cargo/config 
error: could not compile  hack-the-planet  due to 2 previous errors
Rust is asking us for a panic handler, basically I m going to jump to this address if something goes terribly wrong and execute whatever you put there . Eventually we would put some code there to just exit the program, but for now an infinitely loop will do. This is likely going to get stripped away anyway by the compiler if it notices our program has no code-branches leading to a panic and the code is unused. Our src/main.rs now looks like this:
#![no_std]
#![no_main]
use core::panic::PanicInfo;
#[panic_handler]
fn panic(_info: &PanicInfo) -> !  
    loop  
 
Running the build again:
$ cargo build --release --target x86_64-unknown-none
   Compiling hack-the-planet v0.1.0 (/hack-the-planet)
    Finished release [optimized] target(s) in 0.16s
Neat, it worked! What happens if we run it?
$ target/x86_64-unknown-none/release/hack-the-planet
Segmentation fault (core dumped)
Oops. Let s try to disassemble it:
$ objdump -d target/x86_64-unknown-none/release/hack-the-planet
target/x86_64-unknown-none/release/hack-the-planet:     file format elf64-x86-64
Ok that looks pretty from scratch to me . The file contains no cpu instructions. Also note how our infinity loop is not present (as predicted).

Making a basic program and executing it Ok let s try to make a valid program that basically just cleanly exits. First let s try to add some cpu instructions and verify they re indeed getting executed. Lemme introduce, the INT 3 instruction in x86_64 assembly. In binary it s also known as the 0xCC opcode. It crashes our program in a slightly different way, so if the error message changes, we know it worked. The other tutorials use a #[naked] function for the entry point, but since this feature isn t stabilized at the time of writing we re going to use the global_asm! macro. Also don t worry, I m not going to introduce every assembly instruction individually. Our program now looks like this:
#![no_std]
#![no_main]
use core::arch::global_asm;
use core::panic::PanicInfo;
#[panic_handler]
fn panic(_info: &PanicInfo) -> !  
    loop  
 
global_asm!  
    ".global _start",
    "_start:",
    "int 3"
 
Running the build again (ok basically from now on the build is always going to be expected to work unless I say otherwise):
$ cargo build --release --target x86_64-unknown-none
   Compiling hack-the-planet v0.1.0 (/hack-the-planet)
    Finished release [optimized] target(s) in 0.11s
Let s try to disassemble the binary again:
$ objdump -d target/x86_64-unknown-none/release/hack-the-planet
target/x86_64-unknown-none/release/hack-the-planet:     file format elf64-x86-64
Disassembly of section .text:
0000000000001210 <_start>:
    1210:	cc                   	int3
And sure enough, there s a cc instruction that was identified as int3. Let s try to run this:
$ target/x86_64-unknown-none/release/hack-the-planet
Trace/breakpoint trap (core dumped)
The error message of the crash is now slightly different because it s hitting our breakpoint cpu instruction. Funfact btw, if you run this in strace you can see this isn t making any system calls (aka not talking to the kernel at all, it just crashes):
$ strace -f ./hack-the-planet
execve("./hack-the-planet", ["./hack-the-planet"], 0x74f12430d1d8 /* 39 vars */) = 0
--- SIGTRAP  si_signo=SIGTRAP, si_code=SI_KERNEL, si_addr=NULL  ---
+++ killed by SIGTRAP (core dumped) +++
[1]    2796457 trace trap (core dumped)  strace -f ./hack-the-planet
Let s try to make a program that does a clean shutdown. To do this we inform the kernel with a system call that we may like to exit. We can get more info on this with man 2 exit and it defines exit like this:
[[noreturn]] void _exit(int status);
On Linux this syscall is actually called _exit and exit is implemented as a libc function, but we don t care about any of that today, it s going to do the job just fine. Also note how it takes a single argument of type int. In C-speak this means signed 32 bit , i32 in Rust. Next we need to figure out the syscall number of this syscall. These numbers are cpu architecture specific for some reason (idk, idc). We re looking these numbers up with ripgrep in /usr/include/asm/:
$ rg __NR_exit /usr/include/asm
/usr/include/asm/unistd_64.h
64:#define __NR_exit 60
235:#define __NR_exit_group 231
/usr/include/asm/unistd_x32.h
53:#define __NR_exit (__X32_SYSCALL_BIT + 60)
206:#define __NR_exit_group (__X32_SYSCALL_BIT + 231)
/usr/include/asm/unistd_32.h
5:#define __NR_exit 1
253:#define __NR_exit_group 252
Since we re on x86_64 the correct value is the one in unistd_64.h, 60. Also, on x86_64 the syscall number goes into the rax cpu register, the status argument goes in the rdi register. The return value of the syscall is going to be placed in the rax register after the syscall is done, but for exit the execution is never given back to us. Let s try to write 60 into the rax register and 69 into the rdi register. To copy into registers we re going to use the mov destination, source instruction to copy from source to destination. With these registers setup we can use the syscall cpu instruction to hand execution over to the kernel. Don t worry, there s only one more assembly instruction coming and for everything else we re going to use Rust. Our code now looks like this:
#![no_std]
#![no_main]
use core::arch::global_asm;
use core::panic::PanicInfo;
#[panic_handler]
fn panic(_info: &PanicInfo) -> !  
    loop  
 
global_asm!  
    ".global _start",
    "_start:",
    "mov rax, 60",
    "mov rdi, 69",
    "syscall"
 
Build the binary, run it and print the exit code:
$ cargo build --release --target x86_64-unknown-none
$ target/x86_64-unknown-none/release/hack-the-planet; echo $?
69
Nice. Rust is quite literally putting these cpu instructions into the binary for us, nothing else.
$ objdump -d target/x86_64-unknown-none/release/hack-the-planet
target/x86_64-unknown-none/release/hack-the-planet:     file format elf64-x86-64
Disassembly of section .text:
0000000000001210 <_start>:
    1210:	48 c7 c0 3c 00 00 00 	mov    $0x3c,%rax
    1217:	48 c7 c7 45 00 00 00 	mov    $0x45,%rdi
    121e:	0f 05                	syscall
Running this with strace shows the program does exactly one thing.
$ strace -f ./hack-the-planet
execve("./hack-the-planet", ["./hack-the-planet"], 0x70699fe8c908 /* 39 vars */) = 0
exit(69)                                = ?
+++ exited with 69 +++

Writing Rust Ok but even though cpu instructions can be fun at times, I d rather not deal with them most of the time (this might strike you as odd, considering this blog post). Instead let s try to define a function in Rust and call into that instead. We re going to define this function as unsafe (btw none of this is taking advantage of the safety guarantees by Rust in case it wasn t obvious. This tutorial is mostly going to stick to unsafe Rust, but for bigger projects you can attempt to reduce your usage of unsafe to opt back into normal safe Rust), it also declares the function with #[no_mangle] so the function name is preserved as main and we can call it from our global_asm entry point. Lastely, when our program is started it s going to get the stack address passed in one of the cpu registers, this value is expected to be passed to our function as an argument. Our function declares ! as return type, which means it never returns:
#[no_mangle]
unsafe fn main(_stack_top: *const u8) -> !  
    // TODO: this is missing
 
This won t compile yet, we need to add our assembly for the exit syscall back in.
#[no_mangle]
unsafe fn main(_stack_top: *const u8) -> !  
    asm!(
        "syscall",
        in("rax") 60,
        in("rdi") 0,
        options(noreturn)
    );
 
This time we re using the asm! macro, this is a slightly more declarative approach. We want to run the syscall cpu instruction with 60 in the rax register, and this time we want the rdi register to be zero, to indicate a successful exit. We also use options(noreturn) so Rust knows it should assume execution does not resume after this assembly is executed (the Linux kernel guarantees this). We modify our global_asm! entrypoint to call our new main function, and to copy the stack address from rsp into the register for the first argument rdi because it would otherwise get lost forever:
global_asm!  
    ".global _start",
    "_start:",
    "mov rdi, rsp",
    "call main"
 
Our full program now looks like this:
#![no_std]
#![no_main]
use core::arch::asm;
use core::arch::global_asm;
use core::panic::PanicInfo;
#[panic_handler]
fn panic(_info: &PanicInfo) -> !  
    loop  
 
global_asm!  
    ".global _start",
    "_start:",
    "mov rdi, rsp",
    "call main"
 
#[no_mangle]
unsafe fn main(_stack_top: *const u8) -> !  
    asm!(
        "syscall",
        in("rax") 60,
        in("rdi") 0,
        options(noreturn)
    );
 
After building and disassembling this the Rust compiler is slowly starting to do work for us:
$ cargo build --release --target x86_64-unknown-none
$ objdump -d target/x86_64-unknown-none/release/hack-the-planet
target/x86_64-unknown-none/release/hack-the-planet:     file format elf64-x86-64
Disassembly of section .text:
0000000000001210 <_start>:
    1210:	48 89 e7             	mov    %rsp,%rdi
    1213:	e8 08 00 00 00       	call   1220 <main>
    1218:	cc                   	int3
    1219:	cc                   	int3
    121a:	cc                   	int3
    121b:	cc                   	int3
    121c:	cc                   	int3
    121d:	cc                   	int3
    121e:	cc                   	int3
    121f:	cc                   	int3
0000000000001220 <main>:
    1220:	50                   	push   %rax
    1221:	b8 3c 00 00 00       	mov    $0x3c,%eax
    1226:	31 ff                	xor    %edi,%edi
    1228:	0f 05                	syscall
    122a:	0f 0b                	ud2
The mov and syscall instructions are still the same, but it noticed it can XOR the rdi register with itself to set it to zero. It s using x86 assembly language (the 32 bit variant of x86_64, that also happens to work on x86_64) to do so, that s why the register is refered to as edi in the disassembly. You can also see it s inserting a bunch of 0xCC instructions (for alignment) and Rust puts the opcodes 0x0F 0x0B at the end of the function to force an invalid opcode exception so the program is guaranteed to crash in case the exit syscall doesn t do it. This code still executes as expected:
$ strace -f ./hack-the-planet
execve("./hack-the-planet", ["./hack-the-planet"], 0x72dae7e5dc08 /* 39 vars */) = 0
exit(0)                                 = ?
+++ exited with 0 +++

Adding functions Ok we re getting closer but we aren t quite there yet. Let s try to write an exit function for our assembly that we can then call like a normal function. Remember that it takes a signed 32 bit integer that s supposed to go into rdi.
unsafe fn exit(status: i32) -> !  
    asm!(
        "syscall",
        in("rax") 60,
        in("rdi") status,
        options(noreturn)
    );
 
Actually, since this function doesn t take any raw pointers and any i32 is valid for this syscall we re going to remove the unsafe marker of this function. When doing this we still need to use unsafe within the function for our inline assembly.
fn exit(status: i32) -> !  
    unsafe  
        asm!(
            "syscall",
            in("rax") 60,
            in("rdi") status,
            options(noreturn)
        );
     
 
Let s call this function from our main, and also remove the infinity loop of the panic handler with a call to exit(1):
#![no_std]
#![no_main]
use core::arch::asm;
use core::arch::global_asm;
use core::panic::PanicInfo;
#[panic_handler]
fn panic(_info: &PanicInfo) -> !  
    exit(1);
 
global_asm!  
    ".global _start",
    "_start:",
    "mov rdi, rsp",
    "call main"
 
fn exit(status: i32) -> !  
    unsafe  
        asm!(
            "syscall",
            in("rax") 60,
            in("rdi") status,
            options(noreturn)
        );
     
 
#[no_mangle]
unsafe fn main(_stack_top: *const u8) -> !  
    exit(0);
 
Running this still works, but interestingly the generated assembly didn t change at all:
$ cargo build --release --target x86_64-unknown-none
$ objdump -d target/x86_64-unknown-none/release/hack-the-planet
target/x86_64-unknown-none/release/hack-the-planet:     file format elf64-x86-64
Disassembly of section .text:
0000000000001210 <_start>:
    1210:	48 89 e7             	mov    %rsp,%rdi
    1213:	e8 08 00 00 00       	call   1220 <main>
    1218:	cc                   	int3
    1219:	cc                   	int3
    121a:	cc                   	int3
    121b:	cc                   	int3
    121c:	cc                   	int3
    121d:	cc                   	int3
    121e:	cc                   	int3
    121f:	cc                   	int3
0000000000001220 <main>:
    1220:	50                   	push   %rax
    1221:	b8 3c 00 00 00       	mov    $0x3c,%eax
    1226:	31 ff                	xor    %edi,%edi
    1228:	0f 05                	syscall
    122a:	0f 0b                	ud2
Rust noticed there s no need to make it a separate function at runtime and instead merged the instructions of the exit function directly into our main. It also noticed the 0 argument in exit(0) means rdi is supposed to be zero and uses the XOR optimization mentioned before. Since main is not calling any unsafe functions anymore we could mark it as safe too, but in the next few functions we re going to deal with file descriptors and raw pointers, so this is likely the only safe function we re going to write in this tutorial so let s just keep the unsafe marker.

Printing text Ok let s try to do a quick hello world, to do this we re going to call the write syscall. Looking it up with man 2 write:
ssize_t write(int fd, const void buf[.count], size_t count);
The write syscall takes 3 arguments and returns a signed size_t. In Rust this is called isize. In C size_t is an unsigned integer type that can hold any value of sizeof(...) for the given platform, ssize_t can only store half of that because it uses one of the bits to indicate an error has occured (the first s means signed, write returns -1 in case of an error). The arguments for write are:
  • the file descriptor to write to. stdout is located on file descriptor 1.
  • a pointer/address to some memory.
  • the number of bytes that should be written, starting at the given address.
Let s also lookup the syscall number of write:
% rg __NR_write /usr/include/asm
/usr/include/asm/unistd_64.h
5:#define __NR_write 1
24:#define __NR_writev 20
/usr/include/asm/unistd_32.h
8:#define __NR_write 4
150:#define __NR_writev 146
/usr/include/asm/unistd_x32.h
5:#define __NR_write (__X32_SYSCALL_BIT + 1)
323:#define __NR_writev (__X32_SYSCALL_BIT + 516)
The value we re looking for is 1. Let s write our write function (heh).
unsafe fn write(fd: i32, buf: *const u8, count: usize) -> isize  
    let r0;
    asm!(
        "syscall",
        inlateout("rax") 1 => r0,
        in("rdi") fd,
        in("rsi") buf,
        in("rdx") count,
        lateout("rcx") _,
        lateout("r11") _,
        options(nostack, preserves_flags)
    );
    r0
 
Now that s a lot of stuff at once. Since this syscall is actually going to hand execution back to our program we need to let Rust know which cpu registers the syscall is writing to, so Rust doesn t attempt to use them to store data (that would be silently overwritten by the syscall). inlateout("raw") 1 => r0 means we re writing a value to the register and want the result back in variable r0. in("rdi") fd means we want to write the value of fd into the rdi register. lateout("rcx") _ means the Linux kernel may write to that register (so the previous value may get lost), but we don t want to store the value anywhere (the underscore acts as a dummy variable name). This doesn t compile just yet though
$ cargo build --release --target x86_64-unknown-none
   Compiling hack-the-planet v0.1.0 (/hack-the-planet)
error: incompatible types for asm inout argument
  --> src/main.rs:35:26
    
35           inlateout("rax") 1 => r0,
                              ^    ^^ type  isize 
                               
                              type  i32 
    
   = note: asm inout arguments must have the same type, unless they are both pointers or integers of the same size
error: could not compile  hack-the-planet  due to previous error
Rust has inferred the type of r0 is isize since that s what our function returns, but the type of the input value for the register was inferred to be i32. We re going to select a specific number type to fix this.
unsafe fn write(fd: i32, buf: *const u8, count: usize) -> isize  
    let r0;
    asm!(
        "syscall",
        inlateout("rax") 1isize => r0,
        in("rdi") fd,
        in("rsi") buf,
        in("rdx") count,
        lateout("rcx") _,
        lateout("r11") _,
        options(nostack, preserves_flags)
    );
    r0
 
We can now call our new write function like this:
write(1, b"Hello world\n".as_ptr(), 12);
We need to set the number of bytes we want to write explicitly because there s no concept of null-byte termination in the write system call, it s quite literally write the next X bytes, starting from this address . Our program now looks like this:
#![no_std]
#![no_main]
use core::arch::asm;
use core::arch::global_asm;
use core::panic::PanicInfo;
#[panic_handler]
fn panic(_info: &PanicInfo) -> !  
    exit(1);
 
global_asm!  
    ".global _start",
    "_start:",
    "mov rdi, rsp",
    "call main"
 
fn exit(status: i32) -> !  
    unsafe  
        asm!(
            "syscall",
            in("rax") 60,
            in("rdi") status,
            options(noreturn)
        );
     
 
unsafe fn write(fd: i32, buf: *const u8, count: usize) -> isize  
    let r0;
    asm!(
        "syscall",
        inlateout("rax") 1isize => r0,
        in("rdi") fd,
        in("rsi") buf,
        in("rdx") count,
        lateout("rcx") _,
        lateout("r11") _,
        options(nostack, preserves_flags)
    );
    r0
 
#[no_mangle]
unsafe fn main(_stack_top: *const u8) -> !  
    write(1, b"Hello world\n".as_ptr(), 12);
    exit(0);
 
Let s try to build and disassemble it:
$ cargo build --release --target x86_64-unknown-none
$ objdump -d target/x86_64-unknown-none/release/hack-the-planet
target/x86_64-unknown-none/release/hack-the-planet:     file format elf64-x86-64
Disassembly of section .text:
0000000000001220 <_start>:
    1220:	48 89 e7             	mov    %rsp,%rdi
    1223:	e8 08 00 00 00       	call   1230 <main>
    1228:	cc                   	int3
    1229:	cc                   	int3
    122a:	cc                   	int3
    122b:	cc                   	int3
    122c:	cc                   	int3
    122d:	cc                   	int3
    122e:	cc                   	int3
    122f:	cc                   	int3
0000000000001230 <main>:
    1230:	50                   	push   %rax
    1231:	48 8d 35 d5 ef ff ff 	lea    -0x102b(%rip),%rsi        # 20d <_start-0x1013>
    1238:	b8 01 00 00 00       	mov    $0x1,%eax
    123d:	ba 0c 00 00 00       	mov    $0xc,%edx
    1242:	bf 01 00 00 00       	mov    $0x1,%edi
    1247:	0f 05                	syscall
    1249:	b8 3c 00 00 00       	mov    $0x3c,%eax
    124e:	31 ff                	xor    %edi,%edi
    1250:	0f 05                	syscall
    1252:	0f 0b                	ud2
This time there are 2 syscalls, first write, then exit. For write it s setting up the 3 arguments in our cpu registers (rdi, rsi, rdx). The lea instruction subtracts 0x102b from the rip register (the instruction pointer) and places the result in the rsi register. This is effectively saying an address relative to wherever this code was loaded into memory . The instruction pointer is going to point directly behind the opcodes of the lea instruction, so 0x1238 - 0x102b = 0x20d. This address is also pointed out in the disassembly as a comment. We don t see the string in our disassembly but we can convert our 0x20d hex to 525 in decimal and use dd to read 12 bytes from that offset, and sure enough:
$ dd bs=1 skip=525 count=12 if=target/x86_64-unknown-none/release/hack-the-planet
Hello world
12+0 records in
12+0 records out
Execute our binary with strace also shows the new write syscall (and the bytes that are being written mixed up in the output).
$ strace -f ./hack-the-planet
execve("./hack-the-planet", ["./hack-the-planet"], 0x74493abe64a8 /* 39 vars */) = 0
write(1, "Hello world\n", 12Hello world
)           = 12
exit(0)                                 = ?
+++ exited with 0 +++
After running strip on it to remove some symbols the binary is so small, if you open it in a text editor it fits on a screenshot:

22 March 2023

Michael Prokop: Automatically unlocking a LUKS encrypted root filesystem during boot

Update on 2023-03-23: thanks to Daniel Roschka for mentioning the Mandos and TPM approaches, which might be better alternatives, depending on your options and needs. Peter Palfrader furthermore pointed me towards clevis-initramfs and tang. A customer of mine runs dedicated servers inside a foreign data-center, remote hands only. In such an environment you might need a disk replacement because you need bigger or faster disks, though also a disk might (start to) fail and you need a replacement. One has to be prepared for such a scenario, but fully wiping your used disk then might not always be an option, especially once disks (start to) fail. On the other hand you don t want to end up with (partial) data on your disk handed over to someone unexpected. By encrypting the data on your disks upfront you can prevent against this scenario. But if you have a fleet of servers you might not want to manually jump on servers during boot and unlock crypto volumes manually. It s especially annoying if it s about the root filesystem where a solution like dropbear-initramfs needs to be used for remote access during initramfs boot stage. So my task for the customer was to adjust encrypted LUKS devices such that no one needs to manually unlock the encrypted device during server boot (with some specific assumptions about possible attack vectors one has to live with, see the disclaimer at the end). The documentation about this use-case was rather inconsistent, especially because special rules apply for the root filesystem (no key file usage), we see different behavior between what s supported by systemd (hello key file again), initramfs-tools and dracut, not to mention the changes between different distributions. Since tests with this tend to be rather annoying (better make sure to have a Grml live system available :)), I m hereby documenting what worked for us (Debian/bullseye with initramfs-tools and cryptsetup-initramfs). The system was installed with LVM on-top of an encrypted Software-RAID device, only the /boot partition is unencrypted. But even if you don t use Software-RAID nor LVM the same instructions apply. The system looks like this:
% mount -t ext4 -l
/dev/mapper/foobar-root_1 on / type ext4 (rw,relatime,errors=remount-ro)
% sudo pvs
  PV                    VG     Fmt  Attr PSize   PFree
  /dev/mapper/md1_crypt foobar lvm2 a--  445.95g 430.12g
% sudo vgs
  VG     #PV #LV #SN Attr   VSize   VFree
  foobar   1   2   0 wz--n- 445.95g 430.12g
% sudo lvs
  LV     VG     Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root_1 foobar -wi-ao---- <14.90g
% lsblk
NAME                  MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
[...]
sdd                     8:48   0 447.1G  0 disk
 sdd1                  8:49   0   571M  0 part  /boot/efi
 sdd2                  8:50   0   488M  0 part
   md0                 9:0    0   487M  0 raid1 /boot
 sdd3                  8:51   0 446.1G  0 part
   md1                 9:1    0   446G  0 raid1
     md1_crypt       253:0    0   446G  0 crypt
       foobar-root_1 253:1    0  14.9G  0 lvm   /
[...]
sdf                     8:80   0 447.1G  0 disk
 sdf1                  8:81   0   571M  0 part
 sdf2                  8:82   0   488M  0 part
   md0                 9:0    0   487M  0 raid1 /boot
 sdf3                  8:83   0 446.1G  0 part
   md1                 9:1    0   446G  0 raid1
     md1_crypt       253:0    0   446G  0 crypt
       foobar-root_1 253:1    0  14.9G  0 lvm   /
The actual crypsetup configuration is:
% cat /etc/crypttab
md1_crypt UUID=77246138-b666-4151-b01c-5a12db54b28b none luks,discard
Now, to automatically open the crypto device during boot we can instead use:
% cat /etc/crypttab 
md1_crypt UUID=77246138-b666-4151-b01c-5a12db54b28b none luks,discard,keyscript=/etc/initramfs-tools/unlock.sh
# touch /etc/initramfs-tools/unlock.sh
# chmod 0700 /etc/initramfs-tools/unlock.sh
# $EDITOR etc/initramfs-tools/unlock.sh
# cat /etc/initramfs-tools/unlock.sh
#!/bin/sh
echo -n "provide_the_actual_password_here"
# update-initramfs -k all -u
[...]
The server will then boot without prompting for a crypto password. Note that initramfs-tools by default uses an insecure umask of 0022, resulting in the initrd being accessible to everyone. But if you have the dropbear-initramfs package installed, its /usr/share/initramfs-tools/conf-hooks.d/dropbear sets UMASK=0077 , so the resulting /boot/initrd* file should automatically have proper permissions (0600). The cryptsetup hook warns about a permissive umask configuration during update-initramfs runs, but if you want to be sure, explicitly set it via e.g.:
# cat > /etc/initramfs-tools/conf.d/umask << EOF
# restrictive umask to avoid non-root access to initrd:
UMASK=0077
EOF
# update-initramfs -k all -u
Disclaimer: Of course you need to trust users with access to /etc/initramfs-tools/unlock.sh as well as the initramfs/initrd on your system. Furthermore you should wipe the boot partition (to destroy the keyfile information) before handing over such a disk. But that is a risk my customer can live with, YMMV.

13 March 2023

Antoine Beaupr : Framework 12th gen laptop review

The Framework is a 13.5" laptop body with swappable parts, which makes it somewhat future-proof and certainly easily repairable, scoring an "exceedingly rare" 10/10 score from ifixit.com. There are two generations of the laptop's main board (both compatible with the same body): the Intel 11th and 12th gen chipsets. I have received my Framework, 12th generation "DIY", device in late September 2022 and will update this page as I go along in the process of ordering, burning-in, setting up and using the device over the years. Overall, the Framework is a good laptop. I like the keyboard, the touch pad, the expansion cards. Clearly there's been some good work done on industrial design, and it's the most repairable laptop I've had in years. Time will tell, but it looks sturdy enough to survive me many years as well. This is also one of the most powerful devices I ever lay my hands on. I have managed, remotely, more powerful servers, but this is the fastest computer I have ever owned, and it fits in this tiny case. It is an amazing machine. On the downside, there's a bit of proprietary firmware required (WiFi, Bluetooth, some graphics) and the Framework ships with a proprietary BIOS, with currently no Coreboot support. Expect to need the latest kernel, firmware, and hacking around a bunch of things to get resolution and keybindings working right. Like others, I have first found significant power management issues, but many issues can actually be solved with some configuration. Some of the expansion ports (HDMI, DP, MicroSD, and SSD) use power when idle, so don't expect week-long suspend, or "full day" battery while those are plugged in. Finally, the expansion ports are nice, but there's only four of them. If you plan to have a two-monitor setup, you're likely going to need a dock. Read on for the detailed review. For context, I'm moving from the Purism Librem 13v4 because it basically exploded on me. I had, in the meantime, reverted back to an old ThinkPad X220, so I sometimes compare the Framework with that venerable laptop as well. This blog post has been maturing for months now. It started in September 2022 and I declared it completed in March 2023. It's the longest single article on this entire website, currently clocking at about 13,000 words. It will take an average reader a full hour to go through this thing, so I don't expect anyone to actually do that. This introduction should be good enough for most people, read the first section if you intend to actually buy a Framework. Jump around the table of contents as you see fit for after you did buy the laptop, as it might include some crucial hints on how to make it work best for you, especially on (Debian) Linux.

Advice for buyers Those are things I wish I would have known before buying:
  1. consider buying 4 USB-C expansion cards, or at least a mix of 4 USB-A or USB-C cards, as they use less power than other cards and you do want to fill those expansion slots otherwise they snag around and feel insecure
  2. you will likely need a dock or at least a USB hub if you want a two-monitor setup, otherwise you'll run out of ports
  3. you have to do some serious tuning to get proper (10h+ idle, 10 days suspend) power savings
  4. in particular, beware that the HDMI, DisplayPort and particularly the SSD and MicroSD cards take a significant amount power, even when sleeping, up to 2-6W for the latter two
  5. beware that the MicroSD card is what it says: Micro, normal SD cards won't fit, and while there might be full sized one eventually, it's currently only at the prototyping stage
  6. the Framework monitor has an unusual aspect ratio (3:2): I like it (and it matches classic and digital photography aspect ratio), but it might surprise you

Current status I have the framework! It's setup with a fresh new Debian bookworm installation. I've ran through a large number of tests and burn in. I have decided to use the Framework as my daily driver, and had to buy a USB-C dock to get my two monitors connected, which was own adventure. Update: Framework just (2023-03-23) just announced a whole bunch of new stuff: The recording is available in this video and it's not your typical keynote. It starts ~25 minutes late, audio is crap, lightning and camera are crap, clapping seems to be from whatever staff they managed to get together in a room, decor is bizarre, colors are shit. It's amazing.

Specifications Those are the specifications of the 12th gen, in general terms. Your build will of course vary according to your needs.
  • CPU: i5-1240P, i7-1260P, or i7-1280P (Up to 4.4-4.8 GHz, 4+8 cores), Iris Xe graphics
  • Storage: 250-4000GB NVMe (or bring your own)
  • Memory: 8-64GB DDR4-3200 (or bring your own)
  • WiFi 6e (AX210, vPro optional, or bring your own)
  • 296.63mm X 228.98mm X 15.85mm, 1.3Kg
  • 13.5" display, 3:2 ratio, 2256px X 1504px, 100% sRGB, >400 nit
  • 4 x USB-C user-selectable expansion ports, including
    • USB-C
    • USB-A
    • HDMI
    • DP
    • Ethernet
    • MicroSD
    • 250-1000GB SSD
  • 3.5mm combo headphone jack
  • Kill switches for microphone and camera
  • Battery: 55Wh
  • Camera: 1080p 60fps
  • Biometrics: Fingerprint Reader
  • Backlit keyboard
  • Power Adapter: 60W USB-C (or bring your own)
  • ships with a screwdriver/spludger
  • 1 year warranty
  • base price: 1000$CAD, but doesn't give you much, typical builds around 1500-2000$CAD

Actual build This is the actual build I ordered. Amounts in CAD. (1CAD = ~0.75EUR/USD.)

Base configuration
  • CPU: Intel Core i5-1240P (AKA Alder Lake P 8 4.4GHz P-threads, 8 3.2GHz E-threads, 16 total, 28-64W), 1079$
  • Memory: 16GB (1 x 16GB) DDR4-3200, 104$

Customization
  • Keyboard: US English, included

Expansion Cards
  • 2 USB-C $24
  • 3 USB-A $36
  • 2 HDMI $50
  • 1 DP $50
  • 1 MicroSD $25
  • 1 Storage 1TB $199
  • Sub-total: 384$

Accessories
  • Power Adapter - US/Canada $64.00

Total
  • Before tax: 1606$
  • After tax and duties: 1847$
  • Free shipping

Quick evaluation This is basically the TL;DR: here, just focusing on broad pros/cons of the laptop.

Pros

Cons
  • the 11th gen is out of stock, except for the higher-end CPUs, which are much less affordable (700$+)
  • the 12th gen has compatibility issues with Debian, followup in the DebianOn page, but basically: brightness hotkeys, power management, wifi, the webcam is okay even though the chipset is the infamous alder lake because it does not have the fancy camera; most issues currently seem solvable, and upstream is working with mainline to get their shit working
  • 12th gen might have issues with thunderbolt docks
  • they used to have some difficulty keeping up with the orders: first two batches shipped, third batch sold out, fourth batch should have shipped (?) in October 2021. they generally seem to keep up with shipping. update (august 2022): they rolled out a second line of laptops (12th gen), first batch shipped, second batch shipped late, September 2022 batch was generally on time, see this spreadsheet for a crowdsourced effort to track those supply chain issues seem to be under control as of early 2023. I got the Ethernet expansion card shipped within a week.
  • compared to my previous laptop (Purism Librem 13v4), it feels strangely bulkier and heavier; it's actually lighter than the purism (1.3kg vs 1.4kg) and thinner (15.85mm vs 18mm) but the design of the Purism laptop (tapered edges) makes it feel thinner
  • no space for a 2.5" drive
  • rather bright LED around power button, but can be dimmed in the BIOS (not low enough to my taste) I got used to it
  • fan quiet when idle, but can be noisy when running, for example if you max a CPU for a while
  • battery described as "mediocre" by Ars Technica (above), confirmed poor in my tests (see below)
  • no RJ-45 port, and attempts at designing ones are failing because the modular plugs are too thin to fit (according to Linux After Dark), so unlikely to have one in the future Update: they cracked that nut and ship an 2.5 gbps Ethernet expansion card with a realtek chipset, without any firmware blob (!)
  • a bit pricey for the performance, especially when compared to the competition (e.g. Dell XPS, Apple M1)
  • 12th gen Intel has glitchy graphics, seems like Intel hasn't fully landed proper Linux support for that chipset yet

Initial hardware setup A breeze.

Accessing the board The internals are accessed through five TorX screws, but there's a nice screwdriver/spudger that works well enough. The screws actually hold in place so you can't even lose them. The first setup is a bit counter-intuitive coming from the Librem laptop, as I expected the back cover to lift and give me access to the internals. But instead the screws is release the keyboard and touch pad assembly, so you actually need to flip the laptop back upright and lift the assembly off (!) to get access to the internals. Kind of scary. I also actually unplugged a connector in lifting the assembly because I lifted it towards the monitor, while you actually need to lift it to the right. Thankfully, the connector didn't break, it just snapped off and I could plug it back in, no harm done. Once there, everything is well indicated, with QR codes all over the place supposedly leading to online instructions.

Bad QR codes Unfortunately, the QR codes I tested (in the expansion card slot, the memory slot and CPU slots) did not actually work so I wonder how useful those actually are. After all, they need to point to something and that means a URL, a running website that will answer those requests forever. I bet those will break sooner than later and in fact, as far as I can tell, they just don't work at all. I prefer the approach taken by the MNT reform here which designed (with the 100 rabbits folks) an actual paper handbook (PDF). The first QR code that's immediately visible from the back of the laptop, in an expansion cord slot, is a 404. It seems to be some serial number URL, but I can't actually tell because, well, the page is a 404. I was expecting that bar code to lead me to an introduction page, something like "how to setup your Framework laptop". Support actually confirmed that it should point a quickstart guide. But in a bizarre twist, they somehow sent me the URL with the plus (+) signs escaped, like this:
https://guides.frame.work/Guide/Framework\+Laptop\+DIY\+Edition\+Quick\+Start\+Guide/57
... which Firefox immediately transforms in:
https://guides.frame.work/Guide/Framework/+Laptop/+DIY/+Edition/+Quick/+Start/+Guide/57
I'm puzzled as to why they would send the URL that way, the proper URL is of course:
https://guides.frame.work/Guide/Framework+Laptop+DIY+Edition+Quick+Start+Guide/57
(They have also "let the team know about this for feedback and help resolve the problem with the link" which is a support code word for "ha-ha! nope! not my problem right now!" Trust me, I know, my own code word is "can you please make a ticket?")

Seating disks and memory The "DIY" kit doesn't actually have that much of a setup. If you bought RAM, it's shipped outside the laptop in a little plastic case, so you just seat it in as usual. Then you insert your NVMe drive, and, if that's your fancy, you also install your own mPCI WiFi card. If you ordered one (which was my case), it's pre-installed. Closing the laptop is also kind of amazing, because the keyboard assembly snaps into place with magnets. I have actually used the laptop with the keyboard unscrewed as I was putting the drives in and out, and it actually works fine (and will probably void your warranty, so don't do that). (But you can.) (But don't, really.)

Hardware review

Keyboard and touch pad The keyboard feels nice, for a laptop. I'm used to mechanical keyboard and I'm rather violent with those poor things. Yet the key travel is nice and it's clickety enough that I don't feel too disoriented. At first, I felt the keyboard as being more laggy than my normal workstation setup, but it turned out this was a graphics driver issues. After enabling a composition manager, everything feels snappy. The touch pad feels good. The double-finger scroll works well enough, and I don't have to wonder too much where the middle button is, it just works. Taps don't work, out of the box: that needs to be enabled in Xorg, with something like this:
cat > /etc/X11/xorg.conf.d/40-libinput.conf <<EOF
Section "InputClass"
      Identifier "libinput touch pad catchall"
      MatchIsTouchpad "on"
      MatchDevicePath "/dev/input/event*"
      Driver "libinput"
      Option "Tapping" "on"
      Option "TappingButtonMap" "lmr"
EndSection
EOF
But be aware that once you enable that tapping, you'll need to deal with palm detection... So I have not actually enabled this in the end.

Power button The power button is a little dangerous. It's quite easy to hit, as it's right next to one expansion card where you are likely to plug in a cable power. And because the expansion cards are kind of hard to remove, you might squeeze the laptop (and the power key) when trying to remove the expansion card next to the power button. So obviously, don't do that. But that's not very helpful. An alternative is to make the power button do something else. With systemd-managed systems, it's actually quite easy. Add a HandlePowerKey stanza to (say) /etc/systemd/logind.conf.d/power-suspends.conf:
[Login]
HandlePowerKey=suspend
HandlePowerKeyLongPress=poweroff
You might have to create the directory first:
mkdir /etc/systemd/logind.conf.d/
Then restart logind:
systemctl restart systemd-logind
And the power button will suspend! Long-press to power off doesn't actually work as the laptop immediately suspends... Note that there's probably half a dozen other ways of doing this, see this, this, or that.

Special keybindings There is a series of "hidden" (as in: not labeled on the key) keybindings related to the fn keybinding that I actually find quite useful.
Key Equivalent Effect Command
p Pause lock screen xset s activate
b Break ? ?
k ScrLk switch keyboard layout N/A
It looks like those are defined in the microcontroller so it would be possible to add some. For example, the SysRq key is almost bound to fn s in there. Note that most other shortcuts like this are clearly documented (volume, brightness, etc). One key that's less obvious is F12 that only has the Framework logo on it. That actually calls the keysym XF86AudioMedia which, interestingly, does absolutely nothing here. By default, on Windows, it opens your browser to the Framework website and, on Linux, your "default media player". The keyboard backlight can be cycled with fn-space. The dimmer version is dim enough, and the keybinding is easy to find in the dark. A skinny elephant would be performed with alt PrtScr (above F11) KEY, so for example alt fn F11 b should do a hard reset. This comment suggests you need to hold the fn only if "function lock" is on, but that's actually the opposite of my experience. Out of the box, some of the fn keys don't work. Mute, volume up/down, brightness, monitor changes, and the airplane mode key all do basically nothing. They don't send proper keysyms to Xorg at all. This is a known problem and it's related to the fact that the laptop has light sensors to adjust the brightness automatically. Somehow some of those keys (e.g. the brightness controls) are supposed to show up as a different input device, but don't seem to work correctly. It seems like the solution is for the Framework team to write a driver specifically for this, but so far no progress since July 2022. In the meantime, the fancy functionality can be supposedly disabled with:
echo 'blacklist hid_sensor_hub'   sudo tee /etc/modprobe.d/framework-als-blacklist.conf
... and a reboot. This solution is also documented in the upstream guide. Note that there's another solution flying around that fixes this by changing permissions on the input device but I haven't tested that or seen confirmation it works.

Kill switches The Framework has two "kill switches": one for the camera and the other for the microphone. The camera one actually disconnects the USB device when turned off, and the mic one seems to cut the circuit. It doesn't show up as muted, it just stops feeding the sound. Both kill switches are around the main camera, on top of the monitor, and quite discreet. Then turn "red" when enabled (i.e. "red" means "turned off").

Monitor The monitor looks pretty good to my untrained eyes. I have yet to do photography work on it, but some photos I looked at look sharp and the colors are bright and lively. The blacks are dark and the screen is bright. I have yet to use it in full sunlight. The dimmed light is very dim, which I like.

Screen backlight I bind brightness keys to xbacklight in i3, but out of the box I get this error:
sep 29 22:09:14 angela i3[5661]: No outputs have backlight property
It just requires this blob in /etc/X11/xorg.conf.d/backlight.conf:
Section "Device"
    Identifier  "Card0"
    Driver      "intel"
    Option      "Backlight"  "intel_backlight"
EndSection
This way I can control the actual backlight power with the brightness keys, and they do significantly reduce power usage.

Multiple monitor support I have been able to hook up my two old monitors to the HDMI and DisplayPort expansion cards on the laptop. The lid closes without suspending the machine, and everything works great. I actually run out of ports, even with a 4-port USB-A hub, which gives me a total of 7 ports:
  1. power (USB-C)
  2. monitor 1 (DisplayPort)
  3. monitor 2 (HDMI)
  4. USB-A hub, which adds:
  5. keyboard (USB-A)
  6. mouse (USB-A)
  7. Yubikey
  8. external sound card
Now the latter, I might be able to get rid of if I switch to a combo-jack headset, which I do have (and still need to test). But still, this is a problem. I'll probably need a powered USB-C dock and better monitors, possibly with some Thunderbolt chaining, to save yet more ports. But that means more money into this setup, argh. And figuring out my monitor situation is the kind of thing I'm not that big of a fan of. And neither is shopping for USB-C (or is it Thunderbolt?) hubs. My normal autorandr setup doesn't work: I have tried saving a profile and it doesn't get autodetected, so I also first need to do:
autorandr -l framework-external-dual-lg-acer
The magic:
autorandr -l horizontal
... also works well. The worst problem with those monitors right now is that they have a radically smaller resolution than the main screen on the laptop, which means I need to reset the font scaling to normal every time I switch back and forth between those monitors and the laptop, which means I actually need to do this:
autorandr -l horizontal &&
eho Xft.dpi: 96   xrdb -merge &&
systemctl restart terminal xcolortaillog background-image emacs &&
i3-msg restart
Kind of disruptive.

Expansion ports I ordered a total of 10 expansion ports. I did manage to initialize the 1TB drive as an encrypted storage, mostly to keep photos as this is something that takes a massive amount of space (500GB and counting) and that I (unfortunately) don't work on very often (but still carry around). The expansion ports are fancy and nice, but not actually that convenient. They're a bit hard to take out: you really need to crimp your fingernails on there and pull hard to take them out. There's a little button next to them to release, I think, but at first it feels a little scary to pull those pucks out of there. You get used to it though, and it's one of those things you can do without looking eventually. There's only four expansion ports. Once you have two monitors, the drive, and power plugged in, bam, you're out of ports; there's nowhere to plug my Yubikey. So if this is going to be my daily driver, with a dual monitor setup, I will need a dock, which means more crap firmware and uncertainty, which isn't great. There are actually plans to make a dual-USB card, but that is blocked on designing an actual board for this. I can't wait to see more expansion ports produced. There's a ethernet expansion card which quickly went out of stock basically the day it was announced, but was eventually restocked. I would like to see a proper SD-card reader. There's a MicroSD card reader, but that obviously doesn't work for normal SD cards, which would be more broadly compatible anyways (because you can have a MicroSD to SD card adapter, but I have never heard of the reverse). Someone actually found a SD card reader that fits and then someone else managed to cram it in a 3D printed case, which is kind of amazing. Still, I really like that idea that I can carry all those little adapters in a pouch when I travel and can basically do anything I want. It does mean I need to shuffle through them to find the right one which is a little annoying. I have an elastic band to keep them lined up so that all the ports show the same side, to make it easier to find the right one. But that quickly gets undone and instead I have a pouch full of expansion cards. Another awesome thing with the expansion cards is that they don't just work on the laptop: anything that takes USB-C can take those cards, which means you can use it to connect an SD card to your phone, for backups, for example. Heck, you could even connect an external display to your phone that way, assuming that's supported by your phone of course (and it probably isn't). The expansion ports do take up some power, even when idle. See the power management section below, and particularly the power usage tests for details.

USB-C charging One thing that is really a game changer for me is USB-C charging. It's hard to overstate how convenient this is. I often have a USB-C cable lying around to charge my phone, and I can just grab that thing and pop it in my laptop. And while it will obviously not charge as fast as the provided charger, it will stop draining the battery at least. (As I wrote this, I had the laptop plugged in the Samsung charger that came with a phone, and it was telling me it would take 6 hours to charge the remaining 15%. With the provided charger, that flew down to 15 minutes. Similarly, I can power the laptop from the power grommet on my desk, reducing clutter as I have that single wire out there instead of the bulky power adapter.) I also really like the idea that I can charge my laptop with a power bank or, heck, with my phone, if push comes to shove. (And vice-versa!) This is awesome. And it works from any of the expansion ports, of course. There's a little led next to the expansion ports as well, which indicate the charge status:
  • red/amber: charging
  • white: charged
  • off: unplugged
I couldn't find documentation about this, but the forum answered. This is something of a recurring theme with the Framework. While it has a good knowledge base and repair/setup guides (and the forum is awesome) but it doesn't have a good "owner manual" that shows you the different parts of the laptop and what they do. Again, something the MNT reform did well. Another thing that people are asking about is an external sleep indicator: because the power LED is on the main keyboard assembly, you don't actually see whether the device is active or not when the lid is closed. Finally, I wondered what happens when you plug in multiple power sources and it turns out the charge controller is actually pretty smart: it will pick the best power source and use it. The only downside is it can't use multiple power sources, but that seems like a bit much to ask.

Multimedia and other devices Those things also work:
  • webcam: splendid, best webcam I've ever had (but my standards are really low)
  • onboard mic: works well, good gain (maybe a bit much)
  • onboard speakers: sound okay, a little metal-ish, loud enough to be annoying, see this thread for benchmarks, apparently pretty good speakers
  • combo jack: works, with slight hiss, see below
There's also a light sensor, but it conflicts with the keyboard brightness controls (see above). There's also an accelerometer, but it's off by default and will be removed from future builds.

Combo jack mic tests The Framework laptop ships with a combo jack on the left side, which allows you to plug in a CTIA (source) headset. In human terms, it's a device that has both a stereo output and a mono input, typically a headset or ear buds with a microphone somewhere. It works, which is better than the Purism (which only had audio out), but is on par for the course for that kind of onboard hardware. Because of electrical interference, such sound cards very often get lots of noise from the board. With a Jabra Evolve 40, the built-in USB sound card generates basically zero noise on silence (invisible down to -60dB in Audacity) while plugging it in directly generates a solid -30dB hiss. There is a noise-reduction system in that sound card, but the difference is still quite striking. On a comparable setup (curie, a 2017 Intel NUC), there is also a his with the Jabra headset, but it's quieter, more in the order of -40/-50 dB, a noticeable difference. Interestingly, testing with my Mee Audio Pro M6 earbuds leads to a little more hiss on curie, more on the -35/-40 dB range, close to the Framework. Also note that another sound card, the Antlion USB adapter that comes with the ModMic 4, also gives me pretty close to silence on a quiet recording, picking up less than -50dB of background noise. It's actually probably picking up the fans in the office, which do make audible noises. In other words, the hiss of the sound card built in the Framework laptop is so loud that it makes more noise than the quiet fans in the office. Or, another way to put it is that two USB sound cards (the Jabra and the Antlion) are able to pick up ambient noise in my office but not the Framework laptop. See also my audio page.

Performance tests

Compiling Linux 5.19.11 On a single core, compiling the Debian version of the Linux kernel takes around 100 minutes:
5411.85user 673.33system 1:37:46elapsed 103%CPU (0avgtext+0avgdata 831700maxresident)k
10594704inputs+87448000outputs (9131major+410636783minor)pagefaults 0swaps
This was using 16 watts of power, with full screen brightness. With all 16 cores (make -j16), it takes less than 25 minutes:
19251.06user 2467.47system 24:13.07elapsed 1494%CPU (0avgtext+0avgdata 831676maxresident)k
8321856inputs+87427848outputs (30792major+409145263minor)pagefaults 0swaps
I had to plug the normal power supply after a few minutes because battery would actually run out using my desk's power grommet (34 watts). During compilation, fans were spinning really hard, quite noisy, but not painfully so. The laptop was sucking 55 watts of power, steadily:
  Time    User  Nice   Sys  Idle    IO  Run Ctxt/s  IRQ/s Fork Exec Exit  Watts
-------- ----- ----- ----- ----- ----- ---- ------ ------ ---- ---- ---- ------
 Average  87.9   0.0  10.7   1.4   0.1 17.8 6583.6 5054.3 233.0 223.9 233.1  55.96
 GeoMean  87.9   0.0  10.6   1.2   0.0 17.6 6427.8 5048.1 227.6 218.7 227.7  55.96
  StdDev   1.4   0.0   1.2   0.6   0.2  3.0 1436.8  255.5 50.0 47.5 49.7   0.20
-------- ----- ----- ----- ----- ----- ---- ------ ------ ---- ---- ---- ------
 Minimum  85.0   0.0   7.8   0.5   0.0 13.0 3594.0 4638.0 117.0 111.0 120.0  55.52
 Maximum  90.8   0.0  12.9   3.5   0.8 38.0 10174.0 5901.0 374.0 362.0 375.0  56.41
-------- ----- ----- ----- ----- ----- ---- ------ ------ ---- ---- ---- ------
Summary:
CPU:  55.96 Watts on average with standard deviation 0.20
Note: power read from RAPL domains: package-0, uncore, package-0, core, psys.
These readings do not cover all the hardware in this device.

memtest86+ I ran Memtest86+ v6.00b3. It shows something like this:
Memtest86+ v6.00b3        12th Gen Intel(R) Core(TM) i5-1240P
CLK/Temp: 2112MHz    78/78 C   Pass  2% #
L1 Cache:   48KB    414 GB/s   Test 46% ##################
L2 Cache: 1.25MB    118 GB/s   Test #3 [Moving inversions, 1s & 0s] 
L3 Cache:   12MB     43 GB/s   Testing: 16GB - 18GB [1GB of 15.7GB]
Memory  :  15.7GB  14.9 GB/s   Pattern: 
--------------------------------------------------------------------------------
CPU: 4P+8E-Cores (16T)    SMP: 8T (PAR))    Time:  0:27:23  Status: Pass     \
RAM: 1600MHz (DDR4-3200) CAS 22-22-22-51    Pass:  1        Errors: 0
--------------------------------------------------------------------------------
Memory SPD Information
----------------------
 - Slot 2: 16GB DDR-4-3200 - Crucial CT16G4SFRA32A.C16FP (2022-W23)
                          Framework FRANMACP04
 <ESC> Exit  <F1> Configuration  <Space> Scroll Lock            6.00.unknown.x64
So about 30 minutes for a full 16GB memory test.

Software setup Once I had everything in the hardware setup, I figured, voil , I'm done, I'm just going to boot this beautiful machine and I can get back to work. I don't understand why I am so na ve some times. It's mind boggling. Obviously, it didn't happen that way at all, and I spent the best of the three following days tinkering with the laptop.

Secure boot and EFI First, I couldn't boot off of the NVMe drive I transferred from the previous laptop (the Purism) and the BIOS was not very helpful: it was just complaining about not finding any boot device, without dropping me in the real BIOS. At first, I thought it was a problem with my NVMe drive, because it's not listed in the compatible SSD drives from upstream. But I figured out how to enter BIOS (press F2 manically, of course), which showed the NVMe drive was actually detected. It just didn't boot, because it was an old (2010!!) Debian install without EFI. So from there, I disabled secure boot, and booted a grml image to try to recover. And by "boot" I mean, I managed to get to the grml boot loader which promptly failed to load its own root file system somehow. I still have to investigate exactly what happened there, but it failed some time after the initrd load with:
Unable to find medium containing a live file system
This, it turns out, was fixed in Debian lately, so a daily GRML build will not have this problems. The upcoming 2022 release (likely 2022.10 or 2022.11) will also get the fix. I did manage to boot the development version of the Debian installer which was a surprisingly good experience: it mounted the encrypted drives and did everything pretty smoothly. It even offered me to reinstall the boot loader, but that ultimately (and correctly, as it turns out) failed because I didn't have a /boot/efi partition. At this point, I realized there was no easy way out of this, and I just proceeded to completely reinstall Debian. I had a spare NVMe drive lying around (backups FTW!) so I just swapped that in, rebooted in the Debian installer, and did a clean install. I wanted to switch to bookworm anyways, so I guess that's done too.

Storage limitations Another thing that happened during setup is that I tried to copy over the internal 2.5" SSD drive from the Purism to the Framework 1TB expansion card. There's no 2.5" slot in the new laptop, so that's pretty much the only option for storage expansion. I was tired and did something wrong. I ended up wiping the partition table on the original 2.5" drive. Oops. It might be recoverable, but just restoring the partition table didn't work either, so I'm not sure how I recover the data there. Normally, everything on my laptops and workstations is designed to be disposable, so that wasn't that big of a problem. I did manage to recover most of the data thanks to git-annex reinit, but that was a little hairy.

Bootstrapping Puppet Once I had some networking, I had to install all the packages I needed. The time I spent setting up my workstations with Puppet has finally paid off. What I actually did was to restore two critical directories:
/etc/ssh
/var/lib/puppet
So that I would keep the previous machine's identity. That way I could contact the Puppet server and install whatever was missing. I used my Puppet optimization trick to do a batch install and then I had a good base setup, although not exactly as it was before. 1700 packages were installed manually on angela before the reinstall, and not in Puppet. I did not inspect each one individually, but I did go through /etc and copied over more SSH keys, for backups and SMTP over SSH.

LVFS support It looks like there's support for the (de-facto) standard LVFS firmware update system. At least I was able to update the UEFI firmware with a simple:
apt install fwupd-amd64-signed
fwupdmgr refresh
fwupdmgr get-updates
fwupdmgr update
Nice. The 12th gen BIOS updates, currently (January 2023) beta, can be deployed through LVFS with:
fwupdmgr enable-remote lvfs-testing
echo 'DisableCapsuleUpdateOnDisk=true' >> /etc/fwupd/uefi_capsule.conf 
fwupdmgr update
Those instructions come from the beta forum post. I performed the BIOS update on 2023-01-16T16:00-0500.

Resolution tweaks The Framework laptop resolution (2256px X 1504px) is big enough to give you a pretty small font size, so welcome to the marvelous world of "scaling". The Debian wiki page has a few tricks for this.

Console This will make the console and grub fonts more readable:
cat >> /etc/default/console-setup <<EOF
FONTFACE="Terminus"
FONTSIZE=32x16
EOF
echo GRUB_GFXMODE=1024x768 >> /etc/default/grub
update-grub

Xorg Adding this to your .Xresources will make everything look much bigger:
! 1.5*96
Xft.dpi: 144
Apparently, some of this can also help:
! These might also be useful depending on your monitor and personal preference:
Xft.autohint: 0
Xft.lcdfilter:  lcddefault
Xft.hintstyle:  hintfull
Xft.hinting: 1
Xft.antialias: 1
Xft.rgba: rgb
It my experience it also makes things look a little fuzzier, which is frustrating because you have this awesome monitor but everything looks out of focus. Just bumping Xft.dpi by a 1.5 factor looks good to me. The Debian Wiki has a page on HiDPI, but it's not as good as the Arch Wiki, where the above blurb comes from. I am not using the latter because I suspect it's causing some of the "fuzziness". TODO: find the equivalent of this GNOME hack in i3? (gsettings set org.gnome.mutter experimental-features "['scale-monitor-framebuffer']"), taken from this Framework guide

Issues

BIOS configuration The Framework BIOS has some minor issues. One issue I personally encountered is that I had disabled Quick boot and Quiet boot in the BIOS to diagnose the above boot issues. This, in turn, triggers a bug where the BIOS boot manager (F12) would just hang completely. It would also fail to boot from an external USB drive. The current fix (as of BIOS 3.03) is to re-enable both Quick boot and Quiet boot. Presumably this is something that will get fixed in a future BIOS update. Note that the following keybindings are active in the BIOS POST check:
Key Meaning
F2 Enter BIOS setup menu
F12 Enter BIOS boot manager
Delete Enter BIOS setup menu

WiFi compatibility issues I couldn't make WiFi work at first. Obviously, the default Debian installer doesn't ship with proprietary firmware (although that might change soon) so the WiFi card didn't work out of the box. But even after copying the firmware through a USB stick, I couldn't quite manage to find the right combination of ip/iw/wpa-supplicant (yes, after repeatedly copying a bunch more packages over to get those bootstrapped). (Next time I should probably try something like this post.) Thankfully, I had a little USB-C dongle with a RJ-45 jack lying around. That also required a firmware blob, but it was a single package to copy over, and with that loaded, I had network. Eventually, I did managed to make WiFi work; the problem was more on the side of "I forgot how to configure a WPA network by hand from the commandline" than anything else. NetworkManager worked fine and got WiFi working correctly. Note that this is with Debian bookworm, which has the 5.19 Linux kernel, and with the firmware-nonfree (firmware-iwlwifi, specifically) package.

Battery life I was having between about 7 hours of battery on the Purism Librem 13v4, and that's after a year or two of battery life. Now, I still have about 7 hours of battery life, which is nicer than my old ThinkPad X220 (20 minutes!) but really, it's not that good for a new generation laptop. The 12th generation Intel chipset probably improved things compared to the previous one Framework laptop, but I don't have a 11th gen Framework to compare with). (Note that those are estimates from my status bar, not wall clock measurements. They should still be comparable between the Purism and Framework, that said.) The battery life doesn't seem up to, say, Dell XPS 13, ThinkPad X1, and of course not the Apple M1, where I would expect 10+ hours of battery life out of the box. That said, I do get those kind estimates when the machine is fully charged and idle. In fact, when everything is quiet and nothing is plugged in, I get dozens of hours of battery life estimated (I've seen 25h!). So power usage fluctuates quite a bit depending on usage, which I guess is expected. Concretely, so far, light web browsing, reading emails and writing notes in Emacs (e.g. this file) takes about 8W of power:
Time    User  Nice   Sys  Idle    IO  Run Ctxt/s  IRQ/s Fork Exec Exit  Watts
-------- ----- ----- ----- ----- ----- ---- ------ ------ ---- ---- ---- ------
 Average   1.7   0.0   0.5  97.6   0.2  1.2 4684.9 1985.2 126.6 39.1 128.0   7.57
 GeoMean   1.4   0.0   0.4  97.6   0.1  1.2 4416.6 1734.5 111.6 27.9 113.3   7.54
  StdDev   1.0   0.2   0.2   1.2   0.0  0.5 1584.7 1058.3 82.1 44.0 80.2   0.71
-------- ----- ----- ----- ----- ----- ---- ------ ------ ---- ---- ---- ------
 Minimum   0.2   0.0   0.2  94.9   0.1  1.0 2242.0  698.2 82.0 17.0 82.0   6.36
 Maximum   4.1   1.1   1.0  99.4   0.2  3.0 8687.4 4445.1 463.0 249.0 449.0   9.10
-------- ----- ----- ----- ----- ----- ---- ------ ------ ---- ---- ---- ------
Summary:
System:   7.57 Watts on average with standard deviation 0.71
Expansion cards matter a lot in the battery life (see below for a thorough discussion), my normal setup is 2xUSB-C and 1xUSB-A (yes, with an empty slot, and yes, to save power). Interestingly, playing a video in a (720p) window in a window takes up more power (10.5W) than in full screen (9.5W) but I blame that on my desktop setup (i3 + compton)... Not sure if mpv hits the VA-API, maybe not in windowed mode. Similar results with 1080p, interestingly, except the window struggles to keep up altogether. Full screen playback takes a relatively comfortable 9.5W, which means a solid 5h+ of playback, which is fine by me. Fooling around the web, small edits, youtube-dl, and I'm at around 80% battery after about an hour, with an estimated 5h left, which is a little disappointing. I had a 7h remaining estimate before I started goofing around Discourse, so I suspect the website is a pretty big battery drain, actually. I see about 10-12 W, while I was probably at half that (6-8W) just playing music with mpv in the background... In other words, it looks like editing posts in Discourse with Firefox takes a solid 4-6W of power. Amazing and gross. (When writing about abusive power usage generates more power usage, is that an heisenbug? Or schr dinbug?)

Power management Compared to the Purism Librem 13v4, the ongoing power usage seems to be slightly better. An anecdotal metric is that the Purism would take 800mA idle, while the more powerful Framework manages a little over 500mA as I'm typing this, fluctuating between 450 and 600mA. That is without any active expansion card, except the storage. Those numbers come from the output of tlp-stat -b and, unfortunately, the "ampere" unit makes it quite hard to compare those, because voltage is not necessarily the same between the two platforms.
  • TODO: review Arch Linux's tips on power saving
  • TODO: i915 driver has a lot of parameters, including some about power saving, see, again, the arch wiki, and particularly enable_fbc=1
TL:DR; power management on the laptop is an issue, but there's various tweaks you can make to improve it. Try:
  • powertop --auto-tune
  • apt install tlp && systemctl enable tlp
  • nvme.noacpi=1 mem_sleep_default=deep on the kernel command line may help with standby power usage
  • keep only USB-C expansion cards plugged in, all others suck power even when idle
  • consider upgrading the BIOS to latest beta (3.06 at the time of writing), unverified power savings
  • latest Linux kernels (6.2) promise power savings as well (unverified)
Update: also try to follow the official optimization guide. It was made for Ubuntu but will probably also work for your distribution of choice with a few tweaks. They recommend using tlpui but it's not packaged in Debian. There is, however, a Flatpak release. In my case, it resulted in the following diff to tlp.conf: tlp.patch.

Background on CPU architecture There were power problems in the 11th gen Framework laptop, according to this report from Linux After Dark, so the issues with power management on the Framework are not new. The 12th generation Intel CPU (AKA "Alder Lake") is a big-little architecture with "power-saving" and "performance" cores. There used to be performance problems introduced by the scheduler in Linux 5.16 but those were eventually fixed in 5.18, which uses Intel's hardware as an "intelligent, low-latency hardware-assisted scheduler". According to Phoronix, the 5.19 release improved the power saving, at the cost of some penalty cost. There were also patch series to make the scheduler configurable, but it doesn't look those have been merged as of 5.19. There was also a session about this at the 2022 Linux Plumbers, but they stopped short of talking more about the specific problems Linux is facing in Alder lake:
Specifically, the kernel's energy-aware scheduling heuristics don't work well on those CPUs. A number of features present there complicate the energy picture; these include SMT, Intel's "turbo boost" mode, and the CPU's internal power-management mechanisms. For many workloads, running on an ostensibly more power-hungry Pcore can be more efficient than using an Ecore. Time for discussion of the problem was lacking, though, and the session came to a close.
All this to say that the 12gen Intel line shipped with this Framework series should have better power management thanks to its power-saving cores. And Linux has had the scheduler changes to make use of this (but maybe is still having trouble). In any case, this might not be the source of power management problems on my laptop, quite the opposite. Also note that the firmware updates for various chipsets are supposed to improve things eventually. On the other hand, The Verge simply declared the whole P-series a mistake...

Attempts at improving power usage I did try to follow some of the tips in this forum post. The tricks powertop --auto-tune and tlp's PCIE_ASPM_ON_BAT=powersupersave basically did nothing: I was stuck at 10W power usage in powertop (600+mA in tlp-stat). Apparently, I should be able to reach the C8 CPU power state (or even C9, C10) in powertop, but I seem to be stock at C7. (Although I'm not sure how to read that tab in powertop: in the Core(HW) column there's only C3/C6/C7 states, and most cores are 85% in C7 or maybe C6. But the next column over does show many CPUs in C10 states... As it turns out, the graphics card actually takes up a good chunk of power unless proper power management is enabled (see below). After tweaking this, I did manage to get down to around 7W power usage in powertop. Expansion cards actually do take up power, and so does the screen, obviously. The fully-lit screen takes a solid 2-3W of power compared to the fully dimmed screen. When removing all expansion cards and making the laptop idle, I can spin it down to 4 watts power usage at the moment, and an amazing 2 watts when the screen turned off.

Caveats Abusive (10W+) power usage that I initially found could be a problem with my desktop configuration: I have this silly status bar that updates every second and probably causes redraws... The CPU certainly doesn't seem to spin down below 1GHz. Also note that this is with an actual desktop running with everything: it could very well be that some things (I'm looking at you Signal Desktop) take up unreasonable amount of power on their own (hello, 1W/electron, sheesh). Syncthing and containerd (Docker!) also seem to take a good 500mW just sitting there. Beyond my desktop configuration, this could, of course, be a Debian-specific problem; your favorite distribution might be better at power management.

Idle power usage tests Some expansion cards waste energy, even when unused. Here is a summary of the findings from the powerstat page. I also include other devices tested in this page for completeness:
Device Minimum Average Max Stdev Note
Screen, 100% 2.4W 2.6W 2.8W N/A
Screen, 1% 30mW 140mW 250mW N/A
Backlight 1 290mW ? ? ? fairly small, all things considered
Backlight 2 890mW 1.2W 3W? 460mW? geometric progression
Backlight 3 1.69W 1.5W 1.8W? 390mW? significant power use
Radios 100mW 250mW N/A N/A
USB-C N/A N/A N/A N/A negligible power drain
USB-A 10mW 10mW ? 10mW almost negligible
DisplayPort 300mW 390mW 600mW N/A not passive
HDMI 380mW 440mW 1W? 20mW not passive
1TB SSD 1.65W 1.79W 2W 12mW significant, probably higher when busy
MicroSD 1.6W 3W 6W 1.93W highest power usage, possibly even higher when busy
Ethernet 1.69W 1.64W 1.76W N/A comparable to the SSD card
So it looks like all expansion cards but the USB-C ones are active, i.e. they draw power with idle. The USB-A cards are the least concern, sucking out 10mW, pretty much within the margin of error. But both the DisplayPort and HDMI do take a few hundred miliwatts. It looks like USB-A connectors have this fundamental flaw that they necessarily draw some powers because they lack the power negotiation features of USB-C. At least according to this post:
It seems the USB A must have power going to it all the time, that the old USB 2 and 3 protocols, the USB C only provides power when there is a connection. Old versus new.
Apparently, this is a problem specific to the USB-C to USB-A adapter that ships with the Framework. Some people have actually changed their orders to all USB-C because of this problem, but I'm not sure the problem is as serious as claimed in the forums. I couldn't reproduce the "one watt" power drains suggested elsewhere, at least not repeatedly. (A previous version of this post did show such a power drain, but it was in a less controlled test environment than the series of more rigorous tests above.) The worst offenders are the storage cards: the SSD drive takes at least one watt of power and the MicroSD card seems to want to take all the way up to 6 watts of power, both just sitting there doing nothing. This confirms claims of 1.4W for the SSD (but not 5W) power usage found elsewhere. The former post has instructions on how to disable the card in software. The MicroSD card has been reported as using 2 watts, but I've seen it as high as 6 watts, which is pretty damning. The Framework team has a beta update for the DisplayPort adapter but currently only for Windows (LVFS technically possible, "under investigation"). A USB-A firmware update is also under investigation. It is therefore likely at least some of those power management issues will eventually be fixed. Note that the upcoming Ethernet card has a reported 2-8W power usage, depending on traffic. I did my own power usage tests in powerstat-wayland and they seem lower than 2W. The upcoming 6.2 Linux kernel might also improve battery usage when idle, see this Phoronix article for details, likely in early 2023.

Idle power usage tests under Wayland Update: I redid those tests under Wayland, see powerstat-wayland for details. The TL;DR: is that power consumption is either smaller or similar.

Idle power usage tests, 3.06 beta BIOS I redid the idle tests after the 3.06 beta BIOS update and ended up with this results:
Device Minimum Average Max Stdev Note
Baseline 1.96W 2.01W 2.11W 30mW 1 USB-C, screen off, backlight off, no radios
2 USB-C 1.95W 2.16W 3.69W 430mW USB-C confirmed as mostly passive...
3 USB-C 1.95W 2.16W 3.69W 430mW ... although with extra stdev
1TB SSD 3.72W 3.85W 4.62W 200mW unchanged from before upgrade
1 USB-A 1.97W 2.18W 4.02W 530mW unchanged
2 USB-A 1.97W 2.00W 2.08W 30mW unchanged
3 USB-A 1.94W 1.99W 2.03W 20mW unchanged
MicroSD w/o card 3.54W 3.58W 3.71W 40mW significant improvement! 2-3W power saving!
MicroSD w/ card 3.53W 3.72W 5.23W 370mW new measurement! increased deviation
DisplayPort 2.28W 2.31W 2.37W 20mW unchanged
1 HDMI 2.43W 2.69W 4.53W 460mW unchanged
2 HDMI 2.53W 2.59W 2.67W 30mW unchanged
External USB 3.85W 3.89W 3.94W 30mW new result
Ethernet 3.60W 3.70W 4.91W 230mW unchanged
Note that the table summary is different than the previous table: here we show the absolute numbers while the previous table was doing a confusing attempt at showing relative (to the baseline) numbers. Conclusion: the 3.06 BIOS update did not significantly change idle power usage stats except for the MicroSD card which has significantly improved. The new "external USB" test is also interesting: it shows how the provided 1TB SSD card performs (admirably) compared to existing devices. The other new result is the MicroSD card with a card which, interestingly, uses less power than the 1TB SSD drive.

Standby battery usage I wrote some quick hack to evaluate how much power is used during sleep. Apparently, this is one of the areas that should have improved since the first Framework model, let's find out. My baseline for comparison is the Purism laptop, which, in 10 minutes, went from this:
sep 28 11:19:45 angela systemd-sleep[209379]: /sys/class/power_supply/BAT/charge_now                      =   6045 [mAh]
... to this:
sep 28 11:29:47 angela systemd-sleep[209725]: /sys/class/power_supply/BAT/charge_now                      =   6037 [mAh]
That's 8mAh per 10 minutes (and 2 seconds), or 48mA, or, with this battery, about 127 hours or roughly 5 days of standby. Not bad! In comparison, here is my really old x220, before:
sep 29 22:13:54 emma systemd-sleep[176315]: /sys/class/power_supply/BAT0/energy_now                     =   5070 [mWh]
... after:
sep 29 22:23:54 emma systemd-sleep[176486]: /sys/class/power_supply/BAT0/energy_now                     =   4980 [mWh]
... which is 90 mwH in 10 minutes, or a whopping 540mA, which was possibly okay when this battery was new (62000 mAh, so about 100 hours, or about 5 days), but this battery is almost dead and has only 5210 mAh when full, so only 10 hours standby. And here is the Framework performing a similar test, before:
sep 29 22:27:04 angela systemd-sleep[4515]: /sys/class/power_supply/BAT1/charge_full                    =   3518 [mAh]
sep 29 22:27:04 angela systemd-sleep[4515]: /sys/class/power_supply/BAT1/charge_now                     =   2861 [mAh]
... after:
sep 29 22:37:08 angela systemd-sleep[4743]: /sys/class/power_supply/BAT1/charge_now                     =   2812 [mAh]
... which is 49mAh in a little over 10 minutes (and 4 seconds), or 292mA, much more than the Purism, but half of the X220. At this rate, the battery would last on standby only 12 hours!! That is pretty bad. Note that this was done with the following expansion cards:
  • 2 USB-C
  • 1 1TB SSD drive
  • 1 USB-A with a hub connected to it, with keyboard and LAN
Preliminary tests without the hub (over one minute) show that it doesn't significantly affect this power consumption (300mA). This guide also suggests booting with nvme.noacpi=1 but this still gives me about 5mAh/min (or 300mA). Adding mem_sleep_default=deep to the kernel command line does make a difference. Before:
sep 29 23:03:11 angela systemd-sleep[3699]: /sys/class/power_supply/BAT1/charge_now                     =   2544 [mAh]
... after:
sep 29 23:04:25 angela systemd-sleep[4039]: /sys/class/power_supply/BAT1/charge_now                     =   2542 [mAh]
... which is 2mAh in 74 seconds, which is 97mA, brings us to a more reasonable 36 hours, or a day and a half. It's still above the x220 power usage, and more than an order of magnitude more than the Purism laptop. It's also far from the 0.4% promised by upstream, which would be 14mA for the 3500mAh battery. It should also be noted that this "deep" sleep mode is a little more disruptive than regular sleep. As you can see by the timing, it took more than 10 seconds for the laptop to resume, which feels a little alarming as your banging the keyboard to bring it back to life. You can confirm the current sleep mode with:
# cat /sys/power/mem_sleep
s2idle [deep]
In the above, deep is selected. You can change it on the fly with:
printf s2idle > /sys/power/mem_sleep
Here's another test:
sep 30 22:25:50 angela systemd-sleep[32207]: /sys/class/power_supply/BAT1/charge_now                     =   1619 [mAh]
sep 30 22:31:30 angela systemd-sleep[32516]: /sys/class/power_supply/BAT1/charge_now                     =   1613 [mAh]
... better! 6 mAh in about 6 minutes, works out to 63.5mA, so more than two days standby. A longer test:
oct 01 09:22:56 angela systemd-sleep[62978]: /sys/class/power_supply/BAT1/charge_now                     =   3327 [mAh]
oct 01 12:47:35 angela systemd-sleep[63219]: /sys/class/power_supply/BAT1/charge_now                     =   3147 [mAh]
That's 180mAh in about 3.5h, 52mA! Now at 66h, or almost 3 days. I wasn't sure why I was seeing such fluctuations in those tests, but as it turns out, expansion card power tests show that they do significantly affect power usage, especially the SSD drive, which can take up to two full watts of power even when idle. I didn't control for expansion cards in the above tests running them with whatever card I had plugged in without paying attention so it's likely the cause of the high power usage and fluctuations. It might be possible to work around this problem by disabling USB devices before suspend. TODO. See also this post. In the meantime, I have been able to get much better suspend performance by unplugging all modules. Then I get this result:
oct 04 11:15:38 angela systemd-sleep[257571]: /sys/class/power_supply/BAT1/charge_now                     =   3203 [mAh]
oct 04 15:09:32 angela systemd-sleep[257866]: /sys/class/power_supply/BAT1/charge_now                     =   3145 [mAh]
Which is 14.8mA! Almost exactly the number promised by Framework! With a full battery, that means a 10 days suspend time. This is actually pretty good, and far beyond what I was expecting when starting down this journey. So, once the expansion cards are unplugged, suspend power usage is actually quite reasonable. More detailed standby tests are available in the standby-tests page, with a summary below. There is also some hope that the Chromebook edition specifically designed with a specification of 14 days standby time could bring some firmware improvements back down to the normal line. Some of those issues were reported upstream in April 2022, but there doesn't seem to have been any progress there since. TODO: one final solution here is suspend-then-hibernate, which Windows uses for this TODO: consider implementing the S0ix sleep states , see also troubleshooting TODO: consider https://github.com/intel/pm-graph

Standby expansion cards test results This table is a summary of the more extensive standby-tests I have performed:
Device Wattage Amperage Days Note
baseline 0.25W 16mA 9 sleep=deep nvme.noacpi=1
s2idle 0.29W 18.9mA ~7 sleep=s2idle nvme.noacpi=1
normal nvme 0.31W 20mA ~7 sleep=s2idle without nvme.noacpi=1
1 USB-C 0.23W 15mA ~10
2 USB-C 0.23W 14.9mA same as above
1 USB-A 0.75W 48.7mA 3 +500mW (!!) for the first USB-A card!
2 USB-A 1.11W 72mA 2 +360mW
3 USB-A 1.48W 96mA <2 +370mW
1TB SSD 0.49W 32mA <5 +260mW
MicroSD 0.52W 34mA ~4 +290mW
DisplayPort 0.85W 55mA <3 +620mW (!!)
1 HDMI 0.58W 38mA ~4 +250mW
2 HDMI 0.65W 42mA <4 +70mW (?)
Conclusions:
  • USB-C cards take no extra power on suspend, possibly less than empty slots, more testing required
  • USB-A cards take a lot more power on suspend (300-500mW) than on regular idle (~10mW, almost negligible)
  • 1TB SSD and MicroSD cards seem to take a reasonable amount of power (260-290mW), compared to their runtime equivalents (1-6W!)
  • DisplayPort takes a surprising lot of power (620mW), almost double its average runtime usage (390mW)
  • HDMI cards take, surprisingly, less power (250mW) in standby than the DP card (620mW)
  • and oddly, a second card adds less power usage (70mW?!) than the first, maybe a circuit is used by both?
A discussion of those results is in this forum post.

Standby expansion cards test results, 3.06 beta BIOS Framework recently (2022-11-07) announced that they will publish a firmware upgrade to address some of the USB-C issues, including power management. This could positively affect the above result, improving both standby and runtime power usage. The update came out in December 2022 and I redid my analysis with the following results:
Device Wattage Amperage Days Note
baseline 0.25W 16mA 9 no cards, same as before upgrade
1 USB-C 0.25W 16mA 9 same as before
2 USB-C 0.25W 16mA 9 same
1 USB-A 0.80W 62mA 3 +550mW!! worse than before
2 USB-A 1.12W 73mA <2 +320mW, on top of the above, bad!
Ethernet 0.62W 40mA 3-4 new result, decent
1TB SSD 0.52W 34mA 4 a bit worse than before (+2mA)
MicroSD 0.51W 22mA 4 same
DisplayPort 0.52W 34mA 4+ upgrade improved by 300mW
1 HDMI ? 38mA ? same
2 HDMI ? 45mA ? a bit worse than before (+3mA)
Normal 1.08W 70mA ~2 Ethernet, 2 USB-C, USB-A
Full results in standby-tests-306. The big takeaway for me is that the update did not improve power usage on the USB-A ports which is a big problem for my use case. There is a notable improvement on the DisplayPort power consumption which brings it more in line with the HDMI connector, but it still doesn't properly turn off on suspend either. Even worse, the USB-A ports now sometimes fails to resume after suspend, which is pretty annoying. This is a known problem that will hopefully get fixed in the final release.

Battery wear protection The BIOS has an option to limit charge to 80% to mitigate battery wear. There's a way to control the embedded controller from runtime with fw-ectool, partly documented here. The command would be:
sudo ectool fwchargelimit 80
I looked at building this myself but failed to run it. I opened a RFP in Debian so that we can ship this in Debian, and also documented my work there. Note that there is now a counter that tracks charge/discharge cycles. It's visible in tlp-stat -b, which is a nice improvement:
root@angela:/home/anarcat# tlp-stat -b
--- TLP 1.5.0 --------------------------------------------
+++ Battery Care
Plugin: generic
Supported features: none available
+++ Battery Status: BAT1
/sys/class/power_supply/BAT1/manufacturer                   = NVT
/sys/class/power_supply/BAT1/model_name                     = Framewo
/sys/class/power_supply/BAT1/cycle_count                    =      3
/sys/class/power_supply/BAT1/charge_full_design             =   3572 [mAh]
/sys/class/power_supply/BAT1/charge_full                    =   3541 [mAh]
/sys/class/power_supply/BAT1/charge_now                     =   1625 [mAh]
/sys/class/power_supply/BAT1/current_now                    =    178 [mA]
/sys/class/power_supply/BAT1/status                         = Discharging
/sys/class/power_supply/BAT1/charge_control_start_threshold = (not available)
/sys/class/power_supply/BAT1/charge_control_end_threshold   = (not available)
Charge                                                      =   45.9 [%]
Capacity                                                    =   99.1 [%]
One thing that is still missing is the charge threshold data (the (not available) above). There's been some work to make that accessible in August, stay tuned? This would also make it possible implement hysteresis support.

Ethernet expansion card The Framework ethernet expansion card is a fancy little doodle: "2.5Gbit/s and 10/100/1000Mbit/s Ethernet", the "clear housing lets you peek at the RTL8156 controller that powers it". Which is another way to say "we didn't completely finish prod on this one, so it kind of looks like we 3D-printed this in the shop".... The card is a little bulky, but I guess that's inevitable considering the RJ-45 form factor when compared to the thin Framework laptop. I have had a serious issue when trying it at first: the link LEDs just wouldn't come up. I made a full bug report in the forum and with upstream support, but eventually figured it out on my own. It's (of course) a power saving issue: if you reboot the machine, the links come up when the laptop is running the BIOS POST check and even when the Linux kernel boots. I first thought that the problem is likely related to the powertop service which I run at boot time to tweak some power saving settings. It seems like this:
echo 'on' > '/sys/bus/usb/devices/4-2/power/control'
... is a good workaround to bring the card back online. You can even return to power saving mode and the card will still work:
echo 'auto' > '/sys/bus/usb/devices/4-2/power/control'
Further research by Matt_Hartley from the Framework Team found this issue in the tlp tracker that shows how the USB_AUTOSUSPEND setting enables the power saving even if the driver doesn't support it, which, in retrospect, just sounds like a bad idea. To quote that issue:
By default, USB power saving is active in the kernel, but not force-enabled for incompatible drivers. That is, devices that support suspension will suspend, drivers that do not, will not.
So the fix is actually to uninstall tlp or disable that setting by adding this to /etc/tlp.conf:
USB_AUTOSUSPEND=0
... but that disables auto-suspend on all USB devices, which may hurt other power usage performance. I have found that a a combination of:
USB_AUTOSUSPEND=1
USB_DENYLIST="0bda:8156"
and this on the kernel commandline:
usbcore.quirks=0bda:8156:k
... actually does work correctly. I now have this in my /etc/default/grub.d/framework-tweaks.cfg file:
# net.ifnames=0: normal interface names ffs (e.g. eth0, wlan0, not wlp166
s0)
# nvme.noacpi=1: reduce SSD disk power usage (not working)
# mem_sleep_default=deep: reduce power usage during sleep (not working)
# usbcore.quirk is a workaround for the ethernet card suspend bug: https:
//guides.frame.work/Guide/Fedora+37+Installation+on+the+Framework+Laptop/
108?lang=en
GRUB_CMDLINE_LINUX="net.ifnames=0 nvme.noacpi=1 mem_sleep_default=deep usbcore.quirks=0bda:8156:k"
# fix the resolution in grub for fonts to not be tiny
GRUB_GFXMODE=1024x768
Other than that, I haven't been able to max out the card because I don't have other 2.5Gbit/s equipment at home, which is strangely satisfying. But running against my Turris Omnia router, I could pretty much max a gigabit fairly easily:
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-10.00  sec  1.09 GBytes   937 Mbits/sec  238             sender
[  5]   0.00-10.00  sec  1.09 GBytes   934 Mbits/sec                  receiver
The card doesn't require any proprietary firmware blobs which is surprising. Other than the power saving issues, it just works. In my power tests (see powerstat-wayland), the Ethernet card seems to use about 1.6W of power idle, without link, in the above "quirky" configuration where the card is functional but without autosuspend.

Proprietary firmware blobs The framework does need proprietary firmware to operate. Specifically:
  • the WiFi network card shipped with the DIY kit is a AX210 card that requires a 5.19 kernel or later, and the firmware-iwlwifi non-free firmware package
  • the Bluetooth adapter also loads the firmware-iwlwifi package (untested)
  • the graphics work out of the box without firmware, but certain power management features come only with special proprietary firmware, normally shipped in the firmware-misc-nonfree but currently missing from the package
Note that, at the time of writing, the latest i915 firmware from linux-firmware has a serious bug where loading all the accessible firmware results in noticeable I estimate 200-500ms lag between the keyboard (not the mouse!) and the display. Symptoms also include tearing and shearing of windows, it's pretty nasty. One workaround is to delete the two affected firmware files:
cd /lib/firmware && rm adlp_guc_70.1.1.bin adlp_guc_69.0.3.bin
update-initramfs -u
You will get the following warning during build, which is good as it means the problematic firmware is disabled:
W: Possible missing firmware /lib/firmware/i915/adlp_guc_69.0.3.bin for module i915
W: Possible missing firmware /lib/firmware/i915/adlp_guc_70.1.1.bin for module i915
But then it also means that critical firmware isn't loaded, which means, among other things, a higher battery drain. I was able to move from 8.5-10W down to the 7W range after making the firmware work properly. This is also after turning the backlight all the way down, as that takes a solid 2-3W in full blast. The proper fix is to use some compositing manager. I ended up using compton with the following systemd unit:
[Unit]
Description=start compositing manager
PartOf=graphical-session.target
ConditionHost=angela
[Service]
Type=exec
ExecStart=compton --show-all-xerrors --backend glx --vsync opengl-swc
Restart=on-failure
[Install]
RequiredBy=graphical-session.target
compton is orphaned however, so you might be tempted to use picom instead, but in my experience the latter uses much more power (1-2W extra, similar experience). I also tried compiz but it would just crash with:
anarcat@angela:~$ compiz --replace
compiz (core) - Warn: No XI2 extension
compiz (core) - Error: Another composite manager is already running on screen: 0
compiz (core) - Fatal: No manageable screens found on display :0
When running from the base session, I would get this instead:
compiz (core) - Warn: No XI2 extension
compiz (core) - Error: Couldn't load plugin 'ccp'
compiz (core) - Error: Couldn't load plugin 'ccp'
Thanks to EmanueleRocca for figuring all that out. See also this discussion about power management on the Framework forum. Note that Wayland environments do not require any special configuration here and actually work better, see my Wayland migration notes for details.
Also note that the iwlwifi firmware also looks incomplete. Even with the package installed, I get those errors in dmesg:
[   19.534429] Intel(R) Wireless WiFi driver for Linux
[   19.534691] iwlwifi 0000:a6:00.0: enabling device (0000 -> 0002)
[   19.541867] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-72.ucode (-2)
[   19.541881] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-72.ucode (-2)
[   19.541882] iwlwifi 0000:a6:00.0: Direct firmware load for iwlwifi-ty-a0-gf-a0-72.ucode failed with error -2
[   19.541890] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-71.ucode (-2)
[   19.541895] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-71.ucode (-2)
[   19.541896] iwlwifi 0000:a6:00.0: Direct firmware load for iwlwifi-ty-a0-gf-a0-71.ucode failed with error -2
[   19.541903] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-70.ucode (-2)
[   19.541907] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-70.ucode (-2)
[   19.541908] iwlwifi 0000:a6:00.0: Direct firmware load for iwlwifi-ty-a0-gf-a0-70.ucode failed with error -2
[   19.541913] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-69.ucode (-2)
[   19.541916] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-69.ucode (-2)
[   19.541917] iwlwifi 0000:a6:00.0: Direct firmware load for iwlwifi-ty-a0-gf-a0-69.ucode failed with error -2
[   19.541922] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-68.ucode (-2)
[   19.541926] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-68.ucode (-2)
[   19.541927] iwlwifi 0000:a6:00.0: Direct firmware load for iwlwifi-ty-a0-gf-a0-68.ucode failed with error -2
[   19.541933] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-67.ucode (-2)
[   19.541937] iwlwifi 0000:a6:00.0: firmware: failed to load iwlwifi-ty-a0-gf-a0-67.ucode (-2)
[   19.541937] iwlwifi 0000:a6:00.0: Direct firmware load for iwlwifi-ty-a0-gf-a0-67.ucode failed with error -2
[   19.544244] iwlwifi 0000:a6:00.0: firmware: direct-loading firmware iwlwifi-ty-a0-gf-a0-66.ucode
[   19.544257] iwlwifi 0000:a6:00.0: api flags index 2 larger than supported by driver
[   19.544270] iwlwifi 0000:a6:00.0: TLV_FW_FSEQ_VERSION: FSEQ Version: 0.63.2.1
[   19.544523] iwlwifi 0000:a6:00.0: firmware: failed to load iwl-debug-yoyo.bin (-2)
[   19.544528] iwlwifi 0000:a6:00.0: firmware: failed to load iwl-debug-yoyo.bin (-2)
[   19.544530] iwlwifi 0000:a6:00.0: loaded firmware version 66.55c64978.0 ty-a0-gf-a0-66.ucode op_mode iwlmvm
Some of those are available in the latest upstream firmware package (iwlwifi-ty-a0-gf-a0-71.ucode, -68, and -67), but not all (e.g. iwlwifi-ty-a0-gf-a0-72.ucode is missing) . It's unclear what those do or don't, as the WiFi seems to work well without them. I still copied them in from the latest linux-firmware package in the hope they would help with power management, but I did not notice a change after loading them. There are also multiple knobs on the iwlwifi and iwlmvm drivers. The latter has a power_schmeme setting which defaults to 2 (balanced), setting it to 3 (low power) could improve battery usage as well, in theory. The iwlwifi driver also has power_save (defaults to disabled) and power_level (1-5, defaults to 1) settings. See also the output of modinfo iwlwifi and modinfo iwlmvm for other driver options.

Graphics acceleration After loading the latest upstream firmware and setting up a compositing manager (compton, above), I tested the classic glxgears. Running in a window gives me odd results, as the gears basically grind to a halt:
Running synchronized to the vertical refresh.  The framerate should be
approximately the same as the monitor refresh rate.
137 frames in 5.1 seconds = 26.984 FPS
27 frames in 5.4 seconds =  5.022 FPS
Ouch. 5FPS! But interestingly, once the window is in full screen, it does hit the monitor refresh rate:
300 frames in 5.0 seconds = 60.000 FPS
I'm not really a gamer and I'm not normally using any of that fancy graphics acceleration stuff (except maybe my browser does?). I installed intel-gpu-tools for the intel_gpu_top command to confirm the GPU was engaged when doing those simulations. A nice find. Other useful diagnostic tools include glxgears and glxinfo (in mesa-utils) and (vainfo in vainfo). Following to this post, I also made sure to have those settings in my about:config in Firefox, or, in user.js:
user_pref("media.ffmpeg.vaapi.enabled", true);
Note that the guide suggests many other settings to tweak, but those might actually be overkill, see this comment and its parents. I did try forcing hardware acceleration by setting gfx.webrender.all to true, but everything became choppy and weird. The guide also mentions installing the intel-media-driver package, but I could not find that in Debian. The Arch wiki has, as usual, an excellent reference on hardware acceleration in Firefox.

Chromium / Signal desktop bugs It looks like both Chromium and Signal Desktop misbehave with my compositor setup (compton + i3). The fix is to add a persistent flag to Chromium. In Arch, it's conveniently in ~/.config/chromium-flags.conf but that doesn't actually work in Debian. I had to put the flag in /etc/chromium.d/disable-compositing, like this:
export CHROMIUM_FLAGS="$CHROMIUM_FLAGS --disable-gpu-compositing"
It's possible another one of the hundreds of flags might fix this issue better, but I don't really have time to go through this entire, incomplete, and unofficial list (!?!). Signal Desktop is a similar problem, and doesn't reuse those flags (because of course it doesn't). Instead I had to rewrite the wrapper script in /usr/local/bin/signal-desktop to use this instead:
exec /usr/bin/flatpak run --branch=stable --arch=x86_64 org.signal.Signal --disable-gpu-compositing "$@"
This was mostly done in this Puppet commit. I haven't figured out the root of this problem. I did try using picom and xcompmgr; they both suffer from the same issue. Another Debian testing user on Wayland told me they haven't seen this problem, so hopefully this can be fixed by switching to wayland.

Graphics card hangs I believe I might have this bug which results in a total graphical hang for 15-30 seconds. It's fairly rare so it's not too disruptive, but when it does happen, it's pretty alarming. The comments on that bug report are encouraging though: it seems this is a bug in either mesa or the Intel graphics driver, which means many people have this problem so it's likely to be fixed. There's actually a merge request on mesa already (2022-12-29). It could also be that bug because the error message I get is actually:
Jan 20 12:49:10 angela kernel: Asynchronous wait on fence 0000:00:02.0:sway[104431]:cb0ae timed out (hint:intel_atomic_commit_ready [i915]) 
Jan 20 12:49:15 angela kernel: i915 0000:00:02.0: [drm] GPU HANG: ecode 12:0:00000000 
Jan 20 12:49:15 angela kernel: i915 0000:00:02.0: [drm] Resetting chip for stopped heartbeat on rcs0 
Jan 20 12:49:15 angela kernel: i915 0000:00:02.0: [drm] GuC firmware i915/adlp_guc_70.1.1.bin version 70.1 
Jan 20 12:49:15 angela kernel: i915 0000:00:02.0: [drm] HuC firmware i915/tgl_huc_7.9.3.bin version 7.9 
Jan 20 12:49:15 angela kernel: i915 0000:00:02.0: [drm] HuC authenticated 
Jan 20 12:49:15 angela kernel: i915 0000:00:02.0: [drm] GuC submission enabled 
Jan 20 12:49:15 angela kernel: i915 0000:00:02.0: [drm] GuC SLPC enabled
It's a solid 30 seconds graphical hang. Maybe the keyboard and everything else keeps working. The latter bug report is quite long, with many comments, but this one from January 2023 seems to say that Sway 1.8 fixed the problem. There's also an earlier patch to add an extra kernel parameter that supposedly fixes that too. There's all sorts of other workarounds in there, for example this:
echo "options i915 enable_dc=1 enable_guc_loading=1 enable_guc_submission=1 edp_vswing=0 enable_guc=2 enable_fbc=1 enable_psr=1 disable_power_well=0"   sudo tee /etc/modprobe.d/i915.conf
from this comment... So that one is unsolved, as far as the upstream drivers are concerned, but maybe could be fixed through Sway.

Weird USB hangs / graphical glitches I have had weird connectivity glitches better described in this post, but basically: my USB keyboard and mice (connected over a USB hub) drop keys, lag a lot or hang, and I get visual glitches. The fix was to tighten the screws around the CPU on the motherboard (!), which is, thankfully, a rather simple repair.

USB docks are hell Note that the monitors are hooked up to angela through a USB-C / Thunderbolt dock from Cable Matters, with the lovely name of 201053-SIL. It has issues, see this blog post for an in-depth discussion.

Shipping details I ordered the Framework in August 2022 and received it about a month later, which is sooner than expected because the August batch was late. People (including me) expected this to have an impact on the September batch, but it seems Framework have been able to fix the delivery problems and keep up with the demand. As of early 2023, their website announces that laptops ship "within 5 days". I have myself ordered a few expansion cards in November 2022, and they shipped on the same day, arriving 3-4 days later.

The supply pipeline There are basically 6 steps in the Framework shipping pipeline, each (except the last) accompanied with an email notification:
  1. pre-order
  2. preparing batch
  3. preparing order
  4. payment complete
  5. shipping
  6. (received)
This comes from the crowdsourced spreadsheet, which should be updated when the status changes here. I was part of the "third batch" of the 12th generation laptop, which was supposed to ship in September. It ended up arriving on my door step on September 27th, about 33 days after ordering. It seems current orders are not processed in "batches", but in real time, see this blog post for details on shipping.

Shipping trivia I don't know about the others, but my laptop shipped through no less than four different airplane flights. Here are the hops it took: I can't quite figure out how to calculate exactly how much mileage that is, but it's huge. The ride through Alaska is surprising enough but the bounce back through Winnipeg is especially weird. I guess the route happens that way because of Fedex shipping hubs. There was a related oddity when I had my Purism laptop shipped: it left from the west coast and seemed to enter on an endless, two week long road trip across the continental US.

Other resources

7 March 2023

Robert McQueen: Flathub in 2023

It s been quite a few months since the most recent updates about Flathub last year. We ve been busy behind the scenes, so I d like to share what we ve been up to at Flathub and why and what s coming up from us this year. I want to focus on: Today Flathub is going strong: we offer 2,000 apps from over 1,500 collaborators on GitHub. We re averaging 700,000 app downloads a day, with 898 million HTTP requests totalling 88.3 TB served by our CDN each day (thank you Fastly!). Flatpak has, in my opinion, solved the largest technical issue which has held back the mainstream growth and acceptance of Linux on the desktop (or other personal computing devices) for the past 25 years: namely, the difficulty for app developers to publish their work in a way that makes it easy for people to discover, download (or sideload, for people in challenging connectivity environments), install and use. Flathub builds on that to help users discover the work of app developers and helps that work reach users in a timely manner. Initial results of this disintermediation are promising: even with its modest size so far, Flathub has hundreds of apps that I have never, ever heard of before and that s even considering I ve been working in the Linux desktop space for nearly 20 years and spent many of those staring at the contents of dselect (showing my age a little) or GNOME Software, attending conferences, and reading blog posts, news articles, and forums. I am also heartened to see that many of our OS distributor partners have recognised that this model is hugely complementary and additive to the indispensable work they are doing to bring the Linux desktop to end users, and that having more apps available to your users is a value-add allowing you to focus on your core offering and not a zero-sum game that should motivate infighting. Ongoing Progress Getting Flathub into its current state has been a long ongoing process. Here s what we ve been up to behind the scenes: Development Last year, we concluded our first engagement with Codethink to build features into the Flathub web app to move from a build service to an app store. That includes accounts for users and developers, payment processing via Stripe, and the ability for developers to manage upload tokens for the apps they control. In parallel, James Westman has been working on app verification and the corresponding features in flat-manager to ensure app metadata accurately reflects verification and pricing, and to provide authentication for paying users for app downloads when the developer enables it. Only verified developers will be able to make direct uploads or access payment settings for their apps. Legal So far, the GNOME Foundation has acted as an incubator and legal host for Flathub even though it s not purely a GNOME product or initiative. Distributing software to end users along with processing and forwarding payments and donations also has a different legal profile in terms of risk exposure and nonprofit compliance than the current activities of the GNOME Foundation. Consequently, we plan to establish an independent legal entity to own and operate Flathub which reduces risk for the GNOME Foundation, better reflects the independent and cross-desktop interests of Flathub, and provides flexibility in the future should we need to change the structure. We re currently in the process of reviewing legal advice to ensure we have the right structure in place before moving forward. Governance As Flathub is something we want to set outside of the existing Linux desktop and distribution space and ensure we represent and serve the widest community of Linux users and developers we ve been working on a governance model that ensures that there is transparency and trust in who is making decisions, and why. We have set up a working group with myself and Mart n Abente Lahaye from GNOME, Aleix Pol Gonzalez, Neofytos Kolokotronis, and Timoth e Ravier from KDE, and Jorge Castro flying the flag for the Flathub community. Thanks also to Neil McGovern and Nick Richards who were also more involved in the process earlier on. We don t want to get held up here creating something complex with memberships and elections, so at first we re going to come up with a simple/balanced way to appoint people into a board that makes key decisions about Flathub and iterate from there. Funding We have received one grant for 2023 of $100K from Endless Network which will go towards the infrastructure, legal, and operations costs of running Flathub and setting up the structure described above. (Full disclosure: Endless Network is the umbrella organisation which also funds my employer, Endless OS Foundation.) I am hoping to grow the available funding to $250K for this year in order to cover the next round of development on the software, prepare for higher operations costs (e.g., accounting gets more complex), and bring in a second full-time staff member in addition to Bart omiej Piotrowski to handle enquiries, reviews, documentation, and partner outreach. We re currently in discussions with NLnet about funding further software development, but have been unfortunately turned down for a grant from the Plaintext Group for this year; this Schmidt Futures project around OSS sustainability is not currently issuing grants in 2023. However, we continue to work on other funding opportunities. Remaining Barriers My personal hypothesis is that our largest remaining barrier to Linux desktop scale and impact is economic. On competing platforms mobile or desktop a developer can offer their work for sale via an app store or direct download with payment or subscription within hours of making a release. While we have taken the time to first download time down from months to days with Flathub, as a community we continue to have a challenging relationship with money. Some creators are lucky enough to have a full-time job within the FLOSS space, while a few superstar developers are able to nurture some level of financial support by investing time in building a following through streaming, Patreon, Kickstarter, or similar. However, a large proportion of us have to make do with the main payback from our labours being a stream of bug reports on GitHub interspersed with occasional conciliatory beers at FOSDEM (other beverages and events are available). The first and most obvious consequence is that if there is no financial payback for participating in developing apps for the free and open source desktop, we will lose many people in the process despite the amazing achievements of those who have brought us to where we are today. As a result, we ll have far fewer developers and apps. If we can t offer access to a growing base of users or the opportunity to offer something of monetary value to them, the reward in terms of adoption and possible payment will be very small. Developers would be forgiven for taking their time and attention elsewhere. With fewer apps, our platform has less to entice and retain prospective users. The second consequence is that this also represents a significant hurdle for diverse and inclusive participation. We essentially require that somebody is in a position of privilege and comfort that they have internet, power, time, and income not to mention childcare, etc. to spare so that they can take part. If that s not the case for somebody, we are leaving them shut out from our community before they even have a chance to start. My belief is that free and open source software represents a better way for people to access computing, and there are billions of people in the world we should hope to reach with our work. But if the mechanism for participation ensures their voices and needs are never represented in our community of creators, we are significantly less likely to understand and meet those needs. While these are my thoughts, you ll notice a strong theme to this year will be leading a consultation process to ensure that we are including, understanding and reflecting the needs of our different communities app creators, OS distributors and Linux users as I don t believe that our initiative will be successful without ensuring mutual benefit and shared success. Ultimately, no matter how beautiful, performant, or featureful the latest versions of the Plasma or GNOME desktops are, or how slick the newly rewritten installer is from your favourite distribution, all of the projects making up the Linux desktop ecosystem are subdividing between ourselves an absolutely tiny market share of the global market of personal computers. To make a bigger mark on the world, as a community, we need to get out more. What s Next? After identifying our major barriers to overcome, we ve planned a number of focused initiatives and restructuring this year: Phased Deployment We re working on deploying the work we have been doing over the past year, starting first with launching the new Flathub web experience as well as the rebrand that Jakub has been talking about on his blog. This also will finally launch the verification features so we can distinguish those apps which are uploaded by their developers. In parallel, we ll also be able to turn on the Flatpak repo subsets that enable users to select only verified and/or FLOSS apps in the Flatpak CLI or their desktop s app center UI. Consultation We would like to make sure that the voices of app creators, OS distributors, and Linux users are reflected in our plans for 2023 and beyond. We will be launching this in the form of Flathub Focus Groups at the Linux App Summit in Brno in May 2023, followed up with surveys and other opportunities for online participation. We see our role as interconnecting communities and want to be sure that we remain transparent and accountable to those we are seeking to empower with our work. Whilst we are being bold and ambitious with what we are trying to create for the Linux desktop community, we also want to make sure we provide the right forums to listen to the FLOSS community and prioritise our work accordingly. Advisory Board As we build the Flathub organisation up in 2023, we re also planning to expand its governance by creating an Advisory Board. We will establish an ongoing forum with different stakeholders around Flathub: OS vendors, hardware integrators, app developers and user representatives to help us create the Flathub that supports and promotes our mutually shared interests in a strong and healthy Linux desktop community. Direct Uploads Direct app uploads are close to ready, and they enable exciting stuff like allowing Electron apps to be built outside of flatpak-builder, or driving automatic Flathub uploads from GitHub actions or GitLab CI flows; however, we need to think a little about how we encourage these to be used. Even with its frustrations, our current Buildbot ensures that the build logs and source versions of each app on Flathub are captured, and that the apps are built on all supported architectures. (Is 2023 when we add RISC-V? Reach out if you d like to help!). If we hand upload tokens out to any developer, even if the majority of apps are open source, we will go from this relatively structured situation to something a lot more unstructured and we fear many apps will be available on only 64-bit Intel/AMD machines. My sketch here is that we need to establish some best practices around how to integrate Flathub uploads into popular CI systems, encouraging best practices so that we promote the properties of transparency and reproducibility that we don t want to lose. If anyone is a CI wizard and would like to work with us as a thought partner about how we can achieve this make it more flexible where and how build tasks can be hosted, but not lose these cross-platform and inspectability properties we d love to hear from you. Donations and Payments Once the work around legal and governance reaches a decent point, we will be in the position to move ahead with our Stripe setup and switch on the third big new feature in the Flathub web app. At present, we have already implemented support for one-off payments either as donations or a required purchase. We would like to go further than that, in line with what we were describing earlier about helping developers sustainably work on apps for our ecosystem: we would also like to enable developers to offer subscriptions. This will allow us to create a relationship between users and creators that funds ongoing work rather than what we already have. Security For Flathub to succeed, we need to make sure that as we grow, we continue to be a platform that can give users confidence in the quality and security of the apps we offer. To that end, we are planning to set up infrastructure to help ensure developers are shipping the best products they possibly can to users. For example, we d like to set up automated linting and security scanning on the Flathub back-end to help developers avoid bad practices, unnecessary sandbox permissions, outdated dependencies, etc. and to keep users informed and as secure as possible. Sponsorship Fundraising is a forever task as is running such a big and growing service. We hope that one day, we can cover our costs through some modest fees built into our payments but until we reach that point, we re going to be seeking a combination of grant funding and sponsorship to keep our roadmap moving. Our hope is very much that we can encourage different organisations that buy into our vision and will benefit from Flathub to help us support it and ensure we can deliver on our goals. If you have any suggestions of who might like to support Flathub, we would be very appreciative if you could reach out and get us in touch. Finally, Thank You! Thanks to you all for reading this far and supporting the work of Flathub, and also to our major sponsors and donors without whom Flathub could not exist: GNOME Foundation, KDE e.V., Mythic Beasts, Endless Network, Fastly, and Equinix Metal via the CNCF Community Cluster. Thanks also to the tireless work of the Freedesktop SDK community to give us the runtime platform most Flatpaks depend on, particularly Seppo Yli-Olli, Codethink and others. I wanted to also give my personal thanks to a handful of dedicated people who keep Flathub working as a service and as a community: Bart omiej Piotrowski is keeping the infrastructure working essentially single-handedly (in his spare time from keeping everything running at GNOME); Kolja Lampe and Bart built the new web app and backend API for Flathub which all of the new functionality has been built on, and Filippe LeMarchand maintains the checker bot which helps keeps all of the Flatpaks up to date. And finally, all of the submissions to Flathub are reviewed to ensure quality, consistency and security by a small dedicated team of reviewers, with a huge amount of work from Hubert Figui re and Bart to keep the submissions flowing. Thanks to everyone named or unnamed for building this vision of the future of the Linux desktop together with us. (originally posted to Flathub Discourse, head there if you have any questions or comments)

5 March 2023

Reproducible Builds: Reproducible Builds in February 2023

Welcome to the February 2023 report from the Reproducible Builds project. As ever, if you are interested in contributing to our project, please visit the Contribute page on our website.
FOSDEM 2023 was held in Brussels on the 4th & 5th of February and featured a number of talks related to reproducibility. In particular, Akihiro Suda gave a talk titled Bit-for-bit reproducible builds with Dockerfile discussing deterministic timestamps and deterministic apt-get (original announcement). There was also an entire track of talks on Software Bill of Materials (SBOMs). SBOMs are an inventory for software with the intention of increasing the transparency of software components (the US National Telecommunications and Information Administration (NTIA) published a useful Myths vs. Facts document in 2021).
On our mailing list this month, Larry Doolittle was puzzled why the Debian verilator package was not reproducible [ ], but Chris Lamb pointed out that this was due to the use of Python s datetime.fromtimestamp over datetime.utcfromtimestamp [ ].
James Addison also was having issues with a Debian package: in this case, the alembic package. Chris Lamb was also able to identify the Sphinx documentation generator as the cause of the problem, and provided a potential patch that might fix it. This was later filed upstream [ ].
Anthony Harrison wrote to our list twice, first by introducing himself and their background and later to mention the increasing relevance of Software Bill of Materials (SBOMs):
As I am sure everyone is aware, there is a growing interest in [SBOMs] as a way of improving software security and resilience. In the last two years, the US through the Exec Order, the EU through the proposed Cyber Resilience Act (CRA) and this month the UK has issued a consultation paper looking at software security and SBOMs appear very prominently in each publication. [ ]

Tim Retout wrote a blog post discussing AlmaLinux in the context of CentOS, RHEL and supply-chain security in general [ ]:
Alma are generating and publishing Software Bill of Material (SBOM) files for every package; these are becoming a requirement for all software sold to the US federal government. What s more, they are sending these SBOMs to a third party (CodeNotary) who store them in some sort of Merkle tree system to make it difficult for people to tamper with later. This should theoretically allow end users of the distribution to verify the supply chain of the packages they have installed?

Debian

F-Droid & Android

diffoscope diffoscope is our in-depth and content-aware diff utility. Not only can it locate and diagnose reproducibility issues, it can provide human-readable diffs from many kinds of binary formats. This month, Chris Lamb released versions 235 and 236; Mattia Rizzolo later released version 237. Contributions include:
  • Chris Lamb:
    • Fix compatibility with PyPDF2 (re. issue #331) [ ][ ][ ].
    • Fix compatibility with ImageMagick version 7.1 [ ].
    • Require at least version 23.1.0 to run the Black source code tests [ ].
    • Update debian/tests/control after merging changes from others [ ].
    • Don t write test data during a test [ ].
    • Update copyright years [ ].
    • Merged a large number of changes from others.
  • Akihiro Suda edited the .gitlab-ci.yml configuration file to ensure that versioned tags are pushed to the container registry [ ].
  • Daniel Kahn Gillmor provided a way to migrate from PyPDF2 to pypdf (#1029741).
  • Efraim Flashner updated the tool metadata for isoinfo on GNU Guix [ ].
  • FC Stegerman added support for Android resources.arsc files [ ], improved a number of file-matching regular expressions [ ][ ] and added support for Android dexdump [ ]; they also fixed a test failure (#1031433) caused by Debian s black package having been updated to a newer version.
  • Mattia Rizzolo:
    • updated the release documentation [ ],
    • fixed a number of Flake8 errors [ ][ ],
    • updated the autopkgtest configuration to only install aapt and dexdump on architectures where they are available [ ], making sure that the latest diffoscope release is in a good fit for the upcoming Debian bookworm freeze.

reprotest Reprotest version 0.7.23 was uploaded to both PyPI and Debian unstable, including the following changes:
  • Holger Levsen improved a lot of documentation [ ][ ][ ], tidied the documentation as well [ ][ ], and experimented with a new --random-locale flag [ ].
  • Vagrant Cascadian adjusted reprotest to no longer randomise the build locale and use a UTF-8 supported locale instead [ ] (re. #925879, #1004950), and to also support passing --vary=locales.locale=LOCALE to specify the locale to vary [ ].
Separate to this, Vagrant Cascadian started a thread on our mailing list questioning the future development and direction of reprotest.

Upstream patches The Reproducible Builds project detects, dissects and attempts to fix as many currently-unreproducible packages as possible. We endeavour to send all of our patches upstream where appropriate. This month, we wrote a large number of such patches, including:

Testing framework The Reproducible Builds project operates a comprehensive testing framework (available at tests.reproducible-builds.org) in order to check packages and other artifacts for reproducibility. In February, the following changes were made by Holger Levsen:
  • Add three new OSUOSL nodes [ ][ ][ ] and decommission the osuosl174 node [ ].
  • Change the order of listed Debian architectures to show the 64-bit ones first [ ].
  • Reduce the frequency that the Debian package sets and dd-list HTML pages update [ ].
  • Sort Tested suite consistently (and Debian unstable first) [ ].
  • Update the Jenkins shell monitor script to only query disk statistics every 230min [ ] and improve the documentation [ ][ ].

Other development work disorderfs version 0.5.11-3 was uploaded by Holger Levsen, fixing a number of issues with the manual page [ ][ ][ ].
Bernhard M. Wiedemann published another monthly report about reproducibility within openSUSE.
If you are interested in contributing to the Reproducible Builds project, please visit the Contribute page on our website. You can get in touch with us via:

28 February 2023

Paul Wise: FLOSS Activities Feb 2023

Focus This month I didn't have any particular focus. I just worked on issues in my info bubble.

Changes

Issues

Review

Administration
  • Debian BTS: unarchive/reopen/triage bugs for reintroduced package servefile
  • Debian IRC: turn an old channel into a redirect to the right one
  • Debian wiki: unblock IP addresses, approve accounts

Communication
  • Respond to queries from Debian users and contributors on the mailing lists and IRC

Sponsors The pyemd/sptag work was sponsored. All other work was done on a volunteer basis.

9 February 2023

Jonathan McDowell: Building a read-only Debian root setup: Part 2

This is the second part of how I build a read-only root setup for my router. You might want to read part 1 first, which covers the initial boot and general overview of how I tie the pieces together. This post will describe how I build the squashfs image that forms the main filesystem. Most of the build is driven from a script, make-router, which I ll dissect below. It s highly tailored to my needs, and this is a fairly lengthy post, but hopefully the steps I describe prove useful to anyone trying to do something similar.
Breakdown of make-router
#!/bin/bash
# Either rb3011 (arm) or rb5009 (arm64)
#HOSTNAME="rb3011"
HOSTNAME="rb5009"
if [ "x$ HOSTNAME " == "xrb3011" ]; then
	ARCH=armhf
elif [ "x$ HOSTNAME " == "xrb5009" ]; then
	ARCH=arm64
else
	echo "Unknown host: $ HOSTNAME "
	exit 1
fi

It s a bash script, and I allow building for either my RB3011 or RB5009, which means a different architecture (32 vs 64 bit). I run this script on my Pi 4 which means I don t have to mess about with QemuUserEmulation.
BASE_DIR=$(dirname $0)
IMAGE_FILE=$(mktemp --tmpdir router.$ ARCH .XXXXXXXXXX.img)
MOUNT_POINT=$(mktemp -p /mnt -d router.$ ARCH .XXXXXXXXXX)
# Build and mount an ext4 image file to put the root file system in
dd if=/dev/zero bs=1 count=0 seek=1G of=$ IMAGE_FILE 
mkfs -t ext4 $ IMAGE_FILE 
mount -o loop $ IMAGE_FILE  $ MOUNT_POINT 

I build the image in a loopback ext4 file on tmpfs (my Pi4 is the 8G model), which makes things a bit faster.
# Add dpkg excludes
mkdir -p $ MOUNT_POINT /etc/dpkg/dpkg.cfg.d/
cat <<EOF > $ MOUNT_POINT /etc/dpkg/dpkg.cfg.d/path-excludes
# Exclude docs
path-exclude=/usr/share/doc/*
# Only locale we want is English
path-exclude=/usr/share/locale/*
path-include=/usr/share/locale/en*/*
path-include=/usr/share/locale/locale.alias
# No man pages
path-exclude=/usr/share/man/*
EOF

Create a dpkg excludes config to drop docs, man pages and most locales before we even start the bootstrap.
# Setup fstab + mtab
echo "# Empty fstab as root is pre-mounted" > $ MOUNT_POINT /etc/fstab
ln -s ../proc/self/mounts $ MOUNT_POINT /etc/mtab
# Setup hostname
echo $ HOSTNAME  > $ MOUNT_POINT /etc/hostname
# Add the root SSH keys
mkdir -p $ MOUNT_POINT /root/.ssh/
cat <<EOF > $ MOUNT_POINT /root/.ssh/authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAv8NkUeVdsVdegS+JT9qwFwiHEgcC9sBwnv6RjpH6I4d3im4LOaPOatzneMTZlH8Gird+H4nzluciBr63hxmcFjZVW7dl6mxlNX2t/wKvV0loxtEmHMoI7VMCnrWD0PyvwJ8qqNu9cANoYriZRhRCsBi27qPNvI741zEpXN8QQs7D3sfe4GSft9yQplfJkSldN+2qJHvd0AHKxRdD+XTxv1Ot26+ZoF3MJ9MqtK+FS+fD9/ESLxMlOpHD7ltvCRol3u7YoaUo2HJ+u31l0uwPZTqkPNS9fkmeCYEE0oXlwvUTLIbMnLbc7NKiLgniG8XaT0RYHtOnoc2l2UnTvH5qsQ== noodles@earth.li
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAACAQDQb9+qFemcwKhey3+eTh5lxp+3sgZXW2HQQEZMt9hPvVXk+MiiNMx9WUzxPJnwXqlmmVdKsq+AvjA0i505Pp8fIj5DdUBpSqpLghmzpnGuob7SSwXYj+352hjD52UC4S0KMKbIaUpklADgsCbtzhYYc4WoO8F7kK63tS5qa1XSZwwRwPbYOWBcNocfr9oXCVWD9ismO8Y0l75G6EyW8UmwYAohDaV83pvJxQerYyYXBGZGY8FNjqVoOGMRBTUcLj/QTo0CDQvMtsEoWeCd0xKLZ3gjiH3UrknkaPra557/TWymQ8Oh15aPFTr5FvKgAlmZaaM0tP71SOGmx7GpCsP4jZD1Xj/7QMTAkLXb+Ou6yUOVM9J4qebdnmF2RGbf1bwo7xSIX6gAYaYgdnppuxqZX1wyAy+A2Hie4tUjMHKJ6OoFwBsV1sl+3FobrPn6IuulRCzsq2aLqLey+PHxuNAYdSKo7nIDB3qCCPwHlDK52WooSuuMidX4ujTUw7LDTia9FxAawudblxbrvfTbg3DsiDBAOAIdBV37HOAKu3VmvYSPyqT80DEy8KFmUpCEau59DID9VERkG6PWPVMiQnqgW2Agn1miOBZeIQV8PFjenAySxjzrNfb4VY/i/kK9nIhXn92CAu4nl6D+VUlw+IpQ8PZlWlvVxAtLonpjxr9OTw== noodles@yubikey
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC0I8UHj4IpfqUcGE4cTvLB0d2xmATSUzqtxW6ZhGbZxvQDKJesVW6HunrJ4NFTQuQJYgOXY/o82qBpkEKqaJMEFHTCjcaj3M6DIaxpiRfQfs0nhtzDB6zPiZn9Suxb0s5Qr4sTWd6iI9da72z3hp9QHNAu4vpa4MSNE+al3UfUisUf4l8TaBYKwQcduCE0z2n2FTi3QzmlkOgH4MgyqBBEaqx1tq7Zcln0P0TYZXFtrxVyoqBBIoIEqYxmFIQP887W50wQka95dBGqjtV+d8IbrQ4pB55qTxMd91L+F8n8A6nhQe7DckjS0Xdla52b9RXNXoobhtvx9K2prisagsHT noodles@cup
ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBK6iGog3WbNhrmrkglNjVO8/B6m7mN6q1tMm1sXjLxQa+F86ETTLiXNeFQVKCHYrk8f7hK0d2uxwgj6Ixy9k0Cw= noodles@sevai
EOF

Setup fstab, the hostname and SSH keys for root.
# Bootstrap our install
debootstrap \
	--arch=$ ARCH  \
	--include=collectd-core,conntrack,dnsmasq,ethtool,iperf3,kexec-tools,mosquitto,mtd-utils,mtr-tiny,ppp,tcpdump,rng-tools5,ssh,watchdog,wget \
	--exclude=dmidecode,isc-dhcp-client,isc-dhcp-common,makedev,nano \
	bullseye $ MOUNT_POINT  https://deb.debian.org/debian/

Actually do the debootstrap step, including a bunch of extra packages that we want.
# Install mqtt-arp
cp $ BASE_DIR /debs/mqtt-arp_1_$ ARCH .deb $ MOUNT_POINT /tmp
chroot $ MOUNT_POINT  dpkg -i /tmp/mqtt-arp_1_$ ARCH .deb
rm $ MOUNT_POINT /tmp/mqtt-arp_1_$ ARCH .deb
# Frob the mqtt-arp config so it starts after mosquitto
sed -i -e 's/After=.*/After=mosquitto.service/' $ MOUNT_POINT /lib/systemd/system/mqtt-arp.service

I haven t uploaded mqtt-arp to Debian, so I install a locally built package, and ensure it starts after mosquitto (the MQTT broker), given they re running on the same host.
# Frob watchdog so it starts earlier than multi-user
sed -i -e 's/After=.*/After=basic.target/' $ MOUNT_POINT /lib/systemd/system/watchdog.service
# Make sure the watchdog is poking the device file
sed -i -e 's/^#watchdog-device/watchdog-device/' $ MOUNT_POINT /etc/watchdog.conf

watchdog timeouts were particularly an issue on the RB3011, where the default timeout didn t give enough time to reach multiuser mode before it would reset the router. Not helpful, so alter the config to start it earlier (and make sure it s configured to actually kick the device file).
# Clean up docs + locales
rm -r $ MOUNT_POINT /usr/share/doc/*
rm -r $ MOUNT_POINT /usr/share/man/*
for dir in $ MOUNT_POINT /usr/share/locale/*/; do
	if [ "$ dir " != "$ MOUNT_POINT /usr/share/locale/en/" ]; then
		rm -r $ dir 
	fi
done

Clean up any docs etc that ended up installed.
# Set root password to root
echo "root:root"   chroot $ MOUNT_POINT  chpasswd

The only login method is ssh key to the root account though I suppose this allows for someone to execute a privilege escalation from a daemon user so I should probably randomise this. Does need to be known though so it s possible to login via the serial console for debugging.
# Add security to sources.list + update
echo "deb https://security.debian.org/debian-security bullseye-security main" >> $ MOUNT_POINT /etc/apt/sources.list
chroot $ MOUNT_POINT  apt update
chroot $ MOUNT_POINT  apt -y full-upgrade
chroot $ MOUNT_POINT  apt clean
# Cleanup the APT lists
rm $ MOUNT_POINT /var/lib/apt/lists/www.*
rm $ MOUNT_POINT /var/lib/apt/lists/security.*

Pull in any security updates, then clean out the APT lists rather than polluting the image with them.
# Disable the daily APT timer
rm $ MOUNT_POINT /etc/systemd/system/timers.target.wants/apt-daily.timer
# Disable daily dpkg backup
cat <<EOF > $ MOUNT_POINT /etc/cron.daily/dpkg
#!/bin/sh
# Don't do the daily dpkg backup
exit 0
EOF
# We don't want a persistent systemd journal
rmdir $ MOUNT_POINT /var/log/journal

None of these make sense on a router.
# Enable nftables
ln -s /lib/systemd/system/nftables.service \
	$ MOUNT_POINT /etc/systemd/system/sysinit.target.wants/nftables.service

Ensure we have firewalling enabled automatically.
# Add systemd-coredump + systemd-timesync user / group
echo "systemd-timesync:x:998:" >> $ MOUNT_POINT /etc/group
echo "systemd-coredump:x:999:" >> $ MOUNT_POINT /etc/group
echo "systemd-timesync:!*::" >> $ MOUNT_POINT /etc/gshadow
echo "systemd-coredump:!*::" >> $ MOUNT_POINT /etc/gshadow
echo "systemd-timesync:x:998:998:systemd Time Synchronization:/:/usr/sbin/nologin" >> $ MOUNT_POINT /etc/passwd
echo "systemd-coredump:x:999:999:systemd Core Dumper:/:/usr/sbin/nologin" >> $ MOUNT_POINT /etc/passwd
echo "systemd-timesync:!*:47358::::::" >> $ MOUNT_POINT /etc/shadow
echo "systemd-coredump:!*:47358::::::" >> $ MOUNT_POINT /etc/shadow
# Create /etc/.pwd.lock, otherwise it'll end up in the overlay
touch $ MOUNT_POINT /etc/.pwd.lock
chmod 600 $ MOUNT_POINT /etc/.pwd.lock

Create a number of users that will otherwise get created at boot, and a lock file that will otherwise get created anyway.
# Copy config files
cp --recursive --preserve=mode,timestamps $ BASE_DIR /etc/* $ MOUNT_POINT /etc/
cp --recursive --preserve=mode,timestamps $ BASE_DIR /etc-$ ARCH /* $ MOUNT_POINT /etc/
chroot $ MOUNT_POINT  chown mosquitto /etc/mosquitto/mosquitto.users
chroot $ MOUNT_POINT  chown mosquitto /etc/ssl/mqtt.home.key

There are config files that are easier to replace wholesale, some of which are specific to the hardware (e.g. related to network interfaces). See below for some more details.
# Build symlinks into flash for boot / modules
ln -s /mnt/flash/lib/modules $ MOUNT_POINT /lib/modules
rmdir $ MOUNT_POINT /boot
ln -s /mnt/flash/boot $ MOUNT_POINT /boot

The kernel + its modules live outside the squashfs image, on the USB flash drive that the image lives on. That makes for easier kernel upgrades.
# Put our git revision into os-release
echo -n "GIT_VERSION=" >> $ MOUNT_POINT /etc/os-release
(cd $ BASE_DIR  ; git describe --tags) >> $ MOUNT_POINT /etc/os-release

Always helpful to be able to check the image itself for what it was built from.
# Add some stuff to root's .bashrc
cat << EOF >> $ MOUNT_POINT /root/.bashrc
alias ls='ls -F --color=auto'
eval "\$(dircolors)"
case "\$TERM" in
xterm* rxvt*)
	PS1="\\[\\e]0;\\u@\\h: \\w\a\\]\$PS1"
	;;
*)
	;;
esac
EOF

Just some niceties for when I do end up logging in.
# Build the squashfs
mksquashfs $ MOUNT_POINT  /tmp/router.$ ARCH .squashfs \
	-comp xz

Actually build the squashfs image.
# Save the installed package list off
chroot $ MOUNT_POINT  dpkg --get-selections > /tmp/wip-installed-packages

Save off the installed package list. This was particularly useful when trying to replicate the existing router setup and making sure I had all the important packages installed. It doesn t really serve a purpose now.
In terms of the config files I copy into /etc, shared across both routers are the following:
Breakdown of shared config
  • apt config (disable recommends, periodic updates):
    • apt/apt.conf.d/10periodic, apt/apt.conf.d/local-recommends
  • Adding a default, empty, locale:
    • default/locale
  • DNS/DHCP:
    • dnsmasq.conf, dnsmasq.d/dhcp-ranges, dnsmasq.d/static-ips
    • hosts, resolv.conf
  • Enabling IP forwarding:
    • sysctl.conf
  • Logs related:
    • logrotate.conf, rsyslog.conf
  • MQTT related:
    • mosquitto/mosquitto.users, mosquitto/conf.d/ssl.conf, mosquitto/conf.d/users.conf, mosquitto/mosquitto.acl, mosquitto/mosquitto.conf
    • mqtt-arp.conf
    • ssl/lets-encrypt-r3.crt, ssl/mqtt.home.key, ssl/mqtt.home.crt
  • PPP configuration:
    • ppp/ip-up.d/0000usepeerdns, ppp/ipv6-up.d/defaultroute, ppp/pap-secrets, ppp/chap-secrets
    • network/interfaces.d/pppoe-wan
The router specific config is mostly related to networking:
Breakdown of router specific config
  • Firewalling:
    • nftables.conf
  • Interfaces:
    • dnsmasq.d/interfaces
    • network/interfaces.d/eth0, network/interfaces.d/p1, network/interfaces.d/p2, network/interfaces.d/p7, network/interfaces.d/p8
  • PPP config (network interface piece):
    • ppp/peers/aquiss
  • SSH keys:
    • ssh/ssh_host_ecdsa_key, ssh/ssh_host_ed25519_key, ssh/ssh_host_rsa_key, ssh/ssh_host_ecdsa_key.pub, ssh/ssh_host_ed25519_key.pub, ssh/ssh_host_rsa_key.pub
  • Monitoring:
    • collectd/collectd.conf, collectd/collectd.conf.d/network.conf

26 January 2023

B lint R czey: How to speed up your next build 5-20x with Firebuild?

Firebuild logo
TL;DR: Just prefix your build command (or any command) with firebuild:
firebuild <build command>
OK, but how does it work? Firebuild intercepts all processes started by the command to cache their outputs. Next time when the command or any of its descendant commands is executed with the same parameters, inputs and environment, the outputs are replayed (the command is shortcut) from the cache instead of running the command again. This is similar to how ccache and other compiler-specific caches work, but firebuild can shortcut any deterministic command, not only a specific list of compilers. Since the inputs of each command is determined at run time firebuild does not need a maintained complete dependency graph in the source like Bazel. It can work with any build system that does not implement its own caching mechanism. Determinism of commands is detected at run-time by preloading libfirebuild.so and interposing standard library calls and syscalls. If the command and all its descendants inputs are available when the command starts and all outputs can be calculated from the inputs then the command can be shortcut, otherwise it will be executed again. The interception comes with a 5-10% overhead, but rebuilds can be 5-20 times, or even faster depending on the changes between the builds. Can I try it? It is already available in Debian Unstable and Testing, Ubuntu s development release and the latest stable version is back-ported to supported Ubuntu releases via a PPA. How can I analyze my builds with firebuild? Firebuild can generate an HTML report showing each command s contribution to the build time. Below are the before and after reports of json4s, a Scala project. The command call graphs (lower ones) show that java (scalac) took 99% of the original build. Since the scalac invocations are shortcut (cutting the second build s time to less than 2% of the first one) they don t even show up in the accelerated second build s call graph. What s left to be executed again in the second run are env, perl, make and a few simple commands. The upper graphs are the process trees, with expandable nodes (in blue) also showing which command invocations were shortcut (green). Clicking on a node shows details of the command and the reason if it was not shortcut. Could I accelerate my project more? Firebuild works best for builds with CPU-intensive processes and comes with defaults to not cache very quick commands, such as sh, grep, sed, etc., because caching those would take cache space and shortcutting them may not speed up the build that much. They can still be shortcut with their parent command. Firebuild s strength is that it can find shortcutting points in the process tree automatically, e.g. from sh -c 'bash -c "sh -c echo Hello World!"' bash would be shortcut, but none of the sh commands would be cached. In typical builds there are many such commands from the skip_cache list. Caching those commands with firebuild -o 'processes.skip_cache = []' can improve acceleration and make the reports smaller. Firebuild also supports several debug flags and -d proc helps finding reasons for not shortcutting some commands:
...
FIREBUILD: Command "/usr/bin/make" can't be short-cut due to: Executable set to be not shortcut,  ExecedProcess 1329.2, running, "make -f debian/rules build", fds=[ FileFD fd=0  FileOFD ...
FIREBUILD: Command "/usr/bin/sort" can't be short-cut due to: Process read from inherited fd ,  ExecedProcess 4161.1, running, "sort", fds=[ FileFD fd=0  FileOFD ...
FIREBUILD: Command "/usr/bin/find" can't be short-cut due to: fstatfs() family operating on fds is not supported,  ExecedProcess 1360.1, running, "find -mindepth 1 ...
...
make, ninja and other incremental build tool binaries are not shortcut because they compare the timestamp of files, but they are fast at least and every build step they perform can still be shortcut. Ideally the slower build steps that could not be shortcut can be re-implemented in ways that can be shortcut by avoiding tools performing unsupported operations. I hope those tools help speeding up your build with very little effort, but if not and you find something to fix or improve in firebuild itself, please report it or just leave a feedback! Happy speeding, but not on public roads!

18 January 2023

Russ Allbery: Review: Forward

Review: Forward, edited by Blake Crouch
Publisher: Amazon Original Stories
Copyright: September 2019
ISBN: 1-5420-9206-X
ISBN: 1-5420-4363-8
ISBN: 1-5420-9357-0
ISBN: 1-5420-0434-9
ISBN: 1-5420-4363-8
ISBN: 1-5420-4425-1
Format: Kindle
Pages: 300
This is another Amazon collection of short fiction, this time mostly at novelette length. (The longer ones might creep into novella.) As before, each one is available separately for purchase or Amazon Prime "borrowing," with separate ISBNs. The sidebar cover is for the first in the sequence. (At some point I need to update my page templates so that I can add multiple covers.) N.K. Jemisin's "Emergency Skin" won the 2020 Hugo Award for Best Novelette, so I wanted to read and review it, but it would be too short for a standalone review. I therefore decided to read the whole collection and review it as an anthology. This was a mistake. Learn from my mistake. The overall theme of the collection is technological advance, rapid change, and the ethical and social question of whether we should slow technology because of social risk. Some of the stories stick to that theme more closely than others. Jemisin's story mostly ignores it, which was probably the right decision. "Ark" by Veronica Roth: A planet-killing asteroid has been on its inexorable way towards Earth for decades. Most of the planet has been evacuated. A small group has stayed behind, cataloging samples and filling two remaining ships with as much biodiversity as they can find with the intent to leave at the last minute. Against that backdrop, two of that team bond over orchids. If you were going "wait, what?" about the successful evacuation of Earth, yeah, me too. No hint is offered as to how this was accomplished. Also, the entirety of humanity abandoned mutual hostility and national borders to cooperate in the face of the incoming disaster, which is, uh, bizarrely optimistic for an otherwise gloomy story. I should be careful about how negative I am about this story because I am sure it will be someone's favorite. I can even write part of the positive review: an elegiac look at loss, choices, and the meaning of a life, a moving look at how people cope with despair. The writing is fine, the story structure works; it's not a bad story. I just found it monumentally depressing, and was not engrossed by the emotionally abused protagonist's unresolved father issues. I can imagine a story around the same facts and plot that I would have liked much better, but all of these people need therapy and better coping mechanisms. I'm also not sure what this had to do with the theme, given that the incoming asteroid is random chance and has nothing to do with technological development. (4) "Summer Frost" by Blake Crouch: The best part of this story is the introductory sequence before the reader knows what's going on, which is full of evocative descriptions. I'm about to spoil what is going on, so if you want to enjoy that untainted by the stupidity of the rest of the plot, skip the rest of this story review. We're going to have a glut of stories about the weird and obsessive form of AI risk invented by the fevered imaginations of the "rationalist" community, aren't we. I don't know why I didn't predict that. It's going to be just as annoying as the glut of cyberpunk novels written by people who don't understand computers. Crouch lost me as soon as the setup is revealed. Even if I believed that a game company would use a deep learning AI still in learning mode to run an NPC (I don't; see Microsoft's Tay for an obvious reason why not), or that such an NPC would spontaneously start testing the boundaries of the game world (this is not how deep learning works), Crouch asks the reader to believe that this AI started as a fully scripted NPC in the prologue with a fixed storyline. In other words, the foundation of the story is that this game company used an AI model capable of becoming a general intelligence for barely more than a cut scene. This is not how anything works. The rest of the story is yet another variation on a science fiction plot so old and threadbare that Isaac Asimov invented the Three Laws of Robotics to avoid telling more versions of it. Crouch's contribution is to dress it up in the terminology of the excessively online. (The middle of the story features a detailed discussion of Roko's basilisk; if you recognize that, you know what you're in for.) Asimov would not have had a lesbian protagonist, so points for progress I guess, but the AI becomes more interesting to the protagonist than her wife and kid because of course it does. There are a few twists and turns along the way, but the destination is the bog-standard hard-takeoff general intelligence scenario. One more pet peeve: Authors, stop trying to illustrate the growth of your AI by having it move from broken to fluent English. English grammar is so much easier than self-awareness or the Turing test that we had programs that could critique your grammar decades before we had believable chatbots. It's going to get grammar right long before the content of the words makes any sense. Also, your AI doesn't sound dumber, your AI sounds like someone whose native language doesn't use pronouns and helper verbs the way that English does, and your decision to use that as a marker for intelligence is, uh, maybe something you should think about. (3) "Emergency Skin" by N.K. Jemisin: The protagonist is a heavily-augmented cyborg from a colony of Earth's diaspora. The founders of that colony fled Earth when it became obvious to them that the planet was dying. They have survived in another star system, but they need a specific piece of technology from the dead remnants of Earth. The protagonist has been sent to retrieve it. The twist is that this story is told in the second-person perspective by the protagonist's ride-along AI, created from a consensus model of the rulers of the colony. We never see directly what the protagonist is doing or thinking, only the AI reaction to it. This is exactly the sort of gimmick that works much better in short fiction than at novel length. Jemisin uses it to create tension between the reader and the narrator, and I thoroughly enjoyed the effect. (As shown in the Broken Earth trilogy, Jemisin is one of the few writers who can use second-person effectively.) I won't spoil the revelation, but it's barbed and biting and vicious and I loved it. Jemisin does deliver the point with a sledgehammer, so be aware of that if you want subtlety in your short fiction, but I prefer the bluntness. (This is part of why I usually don't get along with literary short stories.) The reader of course can't change the direction of the story, but the second-person perspective still provides a hit of vicarious satisfaction. I can see why this won the Hugo; it's worth seeking out. (8) "You Have Arrived at Your Destination" by Amor Towles: Sam and his wife are having a child, and they've decided to provide him with an early boost in life. Vitek is a fertility lab, but more than that, it can do some gene tweaking and adjustment to push a child more towards one personality or another. Sam and his wife have spent hours filling out profiles, and his wife spent hours weeding possible choices down to three. Now, Sam has come to Vitek to pick from the remaining options. Speaking of literary short stories, Towles is the non-SFF writer of this bunch, and it's immediately obvious. The story requires the SFnal premise, but after that this is a character piece. Vitek is an elite, expensive company with a condescending and overly-reductive attitude towards humanity, which is entirely intentional on the author's part. This is the sort of story that gets resolved in an unexpected conversation in a roadside bar, and where most of the conflict happens inside the protagonist's head. I was initially going to complain that Towles does the standard literary thing of leaving off the denouement on the grounds that the reader can figure it out, but when I did a bit of re-reading for this review, I found more of the bones than I had noticed the first time. There's enough subtlety that I had to think for a bit and re-read a passage, but not too much. It's also the most thoughtful treatment of the theme of the collection, the only one that I thought truly wrestled with the weird interactions between technological capability and human foresight. Next to "Emergency Skin," this was the best story of the collection. (7) "The Last Conversation" by Paul Tremblay: A man wakes up in a dark room, in considerable pain, not remembering anything about his life. His only contact with the world at first is a voice: a woman who is helping him recover his strength and his memory. The numbers that head the chapters have significant gaps, representing days left out of the story, as he pieces together what has happened alongside the reader. Tremblay is the horror writer of the collection, so predictably this is the story whose craft I can admire without really liking it. In this case, the horror comes mostly from the pacing of revelation, created by the choice of point of view. (This would be a much different story from the perspective of the woman.) It's well-done, but it has the tendency I've noticed in other horror stories of being a tightly closed system. I see where the connection to the theme is, but it's entirely in the setting, not in the shape of the story. Not my thing, but I can see why it might be someone else's. (5) "Randomize" by Andy Weir: Gah, this was so bad. First, and somewhat expectedly, it's a clunky throwback to a 1950s-style hard SF puzzle story. The writing is atrocious: wooden, awkward, cliched, and full of gratuitous infodumping. The characterization is almost entirely through broad stereotypes; the lone exception is the female character, who at least adds an interesting twist despite being forced to act like an idiot because of the plot. It's a very old-school type of single-twist story, but the ending is completely implausible and falls apart if you breathe on it too hard. Weir is something of a throwback to an earlier era of scientific puzzle stories, though, so maybe one is inclined to give him a break on the writing quality. (I am not; one of the ways in which science fiction has improved is that you can get good scientific puzzles and good writing these days.) But the science is also so bad that I was literally facepalming while reading it. The premise of this story is that quantum computers are commercially available. That will cause a serious problem for Las Vegas casinos, because the generator for keno numbers is vulnerable to quantum algorithms. The solution proposed by the IT person for the casino? A quantum random number generator. (The words "fight quantum with quantum" appear literally in the text if you're wondering how bad the writing is.) You could convince me that an ancient keno system is using a pseudorandom number generator that might be vulnerable to some quantum algorithm and doesn't get reseeded often enough. Fine. And yes, quantum computers can be used to generate high-quality sources of random numbers. But this solution to the problem makes no sense whatsoever. It's like swatting a house fly with a nuclear weapon. Weir says explicitly in the story that all the keno system needs is an external source of high-quality random numbers. The next step is to go to Amazon and buy a hardware random number generator. If you want to splurge, it might cost you $250. Problem solved. Yes, hardware random number generators have various limitations that may cause you problems if you need millions of bits or you need them very quickly, but not for something as dead-simple and with such low entropy requirements as keno numbers! You need a trivial number of bits for each round; even the slowest and most conservative hardware random number generator would be fine. Hell, measure the noise levels on the casino floor. Point a camera at a lava lamp. Or just buy one of the physical ball machines they use for the lottery. This problem is heavily researched, by casinos in particular, and is not significantly changed by the availability of quantum computers, at least for applications such as keno where the generator can be reseeded before each generation. You could maybe argue that this is an excuse for the IT guy to get his hands on a quantum computer, which fits the stereotypes, but that still breaks the story for reasons that would be spoilers. As soon as any other casino thought about this, they'd laugh in the face of the characters. I don't want to make too much of this, since anyone can write one bad story, but this story was dire at every level. I still owe Weir a proper chance at novel length, but I can't say this added to my enthusiasm. (2) Rating: 4 out of 10

Arnaud Rebillout: Build container images in GitLab CI (iptables-legacy at the rescue)

It's 2023 and these days, building a container image in a CI pipeline should be straightforward. So let's try. For this blog post we'll focus on GitLab SaaS only, that is, gitlab.com, as it's what I use for work and for personal projects. To get started, we just need two files in our Git repository: Here is our Git tree:
$ ls -A
Containerfile  .git  .gitlab-ci.yml
$ cat Containerfile 
FROM debian:stable
RUN  apt-get update
CMD  echo hello world
$ cat .gitlab-ci.yml 
build-container-image:
  stage: build
  image: debian:testing
  before_script:
    - apt-get update
    - apt-get install -y buildah ca-certificates
  script:
    - buildah build -t $CI_REGISTRY_IMAGE .
    - buildah login -u $CI_REGISTRY_USER -p $CI_JOB_TOKEN $CI_REGISTRY
    - buildah push $CI_REGISTRY_IMAGE
A few remarks: Now let's push that. Does the CI pass? No, of course, otherwise I wouldn't be writing this blog post ;) The CI fails at the buildah build command, with a rather cryptic error:
$ buildah build --tag $CI_REGISTRY_IMAGE .
[...]
STEP 2/3: RUN  apt-get update
error running container: did not get container start message from parent: EOF
Error: building at STEP "RUN apt-get update": netavark: code: 4, msg: iptables v1.8.8 (nf_tables): Could not fetch rule set generation id: Invalid argument
The hint here is nf_tables... Back in July 2021, GitLab did a major update of their shared runners infrastructure, and broke nftables support in the process, as it seems. So we have to use iptables instead. Let's fix our .gitlab-ci.yml, which now looks like that:
$ cat .gitlab-ci.yml 
build-container-image:
  stage: build
  image: debian:testing
  before_script:
    - apt-get update
    - apt-get install -y buildah ca-certificates
    -  
      # Switch to iptables legacy, as GitLab CI doesn't support nftables.
      apt-get install -y --no-install-recommends iptables
      update-alternatives --set iptables /usr/sbin/iptables-legacy
  script:
    - buildah build -t $CI_REGISTRY_IMAGE .
    - buildah login -u $CI_REGISTRY_USER -p $CI_JOB_TOKEN $CI_REGISTRY
    - buildah push $CI_REGISTRY_IMAGE
And push again. Does that work? Yes! If you're interested in this issue, feel free to fork https://gitlab.com/arnaudr/gitlab-build-container-image and try it by yourself. It's been more than a year since this change, and I'm surprised that I didn't find much about it on the Internet, neither mentions of the issue, nor of a workaround. Maybe nobody builds container images in GitLab CI, or maybe they do it another way, I don't know. In any case, now it's documented in this blog, hopefully some will find it useful. Happy 2023!

5 January 2023

Matthew Garrett: Changing firmware config that doesn't want to be changed

Update: There's actually a more detailed writeup of this here that I somehow missed. Original entry follows:

Today I had to deal with a system that had an irritating restriction - a firmware configuration option I really wanted to be able to change appeared as a greyed out entry in the configuration menu. Some emails revealed that this was a deliberate choice on the part of the system vendor, so that seemed to be that. Thankfully in this case there was a way around that.

One of the things UEFI introduced was a mechanism to generically describe firmware configuration options, called Visual Forms Representation (or VFR). At the most straightforward level, this lets you define a set of forms containing questions, with each question associated with a value in a variable. Questions can be made dependent upon the answers to other questions, so you can have options that appear or disappear based on how other questions were answered. An example in this language might be something like:
CheckBox Prompt: "Console Redirection", Help: "Console Redirection Enable or Disable.", QuestionFlags: 0x10, QuestionId: 53, VarStoreId: 1, VarStoreOffset: 0x39, Flags: 0x0
In which question 53 asks whether console redirection should be enabled or disabled. Other questions can then rely on the answer to question 53 to influence whether or not they're relevant (eg, if console redirection is disabled, there's no point in asking which port it should be redirected to). As a checkbox, if it's set then the value will be set to 1, and 0 otherwise. But where's that stored? Earlier we have another declaration:
VarStore GUID: EC87D643-EBA4-4BB5-A1E5-3F3E36B20DA9, VarStoreId: 1, Size: 0xF4, Name: "Setup"
A UEFI variable called "Setup" and with GUID EC87D643-EBA4-4BB5-A1E5-3F3E36B20DA9 is declared as VarStoreId 1 (matching the declaration in the question) and is 0xf4 bytes long. The question indicates that the offset for that variable is 0x39. Rewriting Setup-EC87D643-EBA4-4BB5-A1E5-3F3E36B20DA9 with a modified value in offset 0x39 will allow direct manipulation of the config option.

But how do we get this data in the first place? VFR isn't built into the firmware directly - instead it's turned into something called Intermediate Forms Representation, or IFR. UEFI firmware images are typically in a standardised format, and you can use UEFITool to extract individual components from that firmware. If you use UEFITool to search for "Setup" there's a good chance you'll be able to find the component that implements the setup UI. Running IFRExtractor-RS against it will then pull out any IFR data it finds, and decompile that into something resembling the original VFR. And now you have the list of variables and offsets and the configuration associated with them, even if your firmware has chosen to hide those options from you.

Given that a bunch of these config values may be security relevant, this seems a little concerning - what stops an attacker who has access to the OS from simply modifying these variables directly? UEFI avoids this by having two separate stages of boot, one where the full firmware ("Boot Services") is available, and one where only a subset ("Runtime Services") is available. The transition is triggered by the OS calling ExitBootServices, indicating the handoff from the firmware owning the hardware to the OS owning the hardware. This is also considered a security boundary - before ExitBootServices everything running has been subject to any secure boot restrictions, and afterwards applications can do whatever they want. UEFI variables can be flagged as being visible in both Boot and Runtime Services, or can be flagged as Boot Services only. As long as all the security critical variables are Boot Services only, an attacker should never be able to run untrusted code that could alter them.

In my case, the firmware option I wanted to alter had been enclosed in "GrayOutIf True" blocks. But the questions were still defined and the code that acted on those options was still present, so simply modifying the variables while still inside Boot Services gave me what I wanted. Note that this isn't a given! The presence of configuration options in the IFR data doesn't mean that anything will later actually read and make use of that variable - a vendor may have flagged options as unavailable and then removed the code, but never actually removed the config data. And also please do note that the reason stuff was removed may have been that it doesn't actually work, and altering any of these variables risks bricking your hardware in a way that's extremely difficult to recover. And there's also no requirement that vendors use IFR to describe their configuration, so you may not get any help here anyway.

In summary: if you do this you may break your computer. If you don't break your computer, it might not work anyway. I'm not going to help you try to break your computer. And I didn't come up with any of this, I just didn't find it all written down in one place while I was researching it.

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30 December 2022

Simon Josefsson: Preseeding Trisquel Virtual Machines Using netinst Images

I m migrating some self-hosted virtual machines to Trisquel, and noticed that Trisquel does not offer cloud-images similar to the Debian Cloud and Ubuntu Cloud images. Thus my earlier approach based on virt-install --cloud-init and cloud-localds does not work with Trisquel. While I hope that Trisquel will eventually publish cloud-compatible images, I wanted to document an alternative approach for Trisquel based on preseeding. This is how I used to install Debian and Ubuntu in the old days, and the automated preseed method is best documented in the Debian installation manual. I was hoping to forget about the preseed format, but maybe it will become one of those legacy technologies that never really disappears? Like FAT16 and 8-bit microcontrollers. Below I assume you have a virtual machine host server up that runs libvirt and has virt-install and similar tools; install them with the following command. I run a pre-release version of Trisquel 11 aramo on my VM-host, but I believe any recent dpkg-based distribution like Trisquel 9/10, PureOS 10, Debian 11 or Ubuntu 20.04/22.04 would work.
apt-get install libvirt-daemon-system virtinst genisoimage cloud-image-utils osinfo-db-tools
The approach can install Trisquel 9 (etiona), Trisquel 10 (nabia) and the pre-release of Trisquel 11. First download and verify the integrity of the netinst images that we will need. Unfortunately the Trisquel 11 netinst beta image does not have any checksum or signature available.
mkdir -p /root/iso
cd /root/iso
wget -q https://mirror.fsf.org/trisquel-images/trisquel-netinst_9.0.2_amd64.iso
wget -q https://mirror.fsf.org/trisquel-images/trisquel-netinst_9.0.2_amd64.iso.asc
wget -q https://mirror.fsf.org/trisquel-images/trisquel-netinst_9.0.2_amd64.iso.sha256
wget -q https://mirror.fsf.org/trisquel-images/trisquel-netinst_10.0.1_amd64.iso
wget -q https://mirror.fsf.org/trisquel-images/trisquel-netinst_10.0.1_amd64.iso.asc
wget -q https://mirror.fsf.org/trisquel-images/trisquel-netinst_10.0.1_amd64.iso.sha256
wget -q -O- https://archive.trisquel.info/trisquel/trisquel-archive-signkey.gpg   gpg --import
sha256sum -c trisquel-netinst_9.0.2_amd64.iso.sha256
gpg --verify trisquel-netinst_9.0.2_amd64.iso.asc
sha256sum -c trisquel-netinst_10.0.1_amd64.iso.sha256
gpg --verify trisquel-netinst_10.0.1_amd64.iso.asc
wget -q https://cdbuilds.trisquel.org/aramo/trisquel-netinst_11.0-20221225_amd64.iso
echo '179566639ca8f14f0c3d5658209c59a0916d9e3bf9c026660cc07b28f2311631  trisquel-netinst_11.0-20221225_amd64.iso'   sha256sum -c
I have developed the following fairly minimal preseed file that works with all three Trisquel releases. Compare it against the official Trisquel 11 preseed skeleton and the Debian 11 example preseed file. You should modify obvious things like SSH key, host/IP settings, partition layout and decide for yourself how to deal with passwords. While Ubuntu/Trisquel usually wants to setup a user account, I prefer to login as root hence setting passwd/root-login to true and passwd/make-user to false.

root@trana:~# cat>trisquel.preseed 
d-i debian-installer/locale select en_US
d-i keyboard-configuration/xkb-keymap select us
d-i netcfg/choose_interface select auto
d-i netcfg/disable_autoconfig boolean true
d-i netcfg/get_ipaddress string 192.168.10.201
d-i netcfg/get_netmask string 255.255.255.0
d-i netcfg/get_gateway string 192.168.10.46
d-i netcfg/get_nameservers string 192.168.10.46
d-i netcfg/get_hostname string trisquel
d-i netcfg/get_domain string sjd.se
d-i clock-setup/utc boolean true
d-i time/zone string UTC
d-i mirror/country string manual
d-i mirror/http/hostname string ftp.acc.umu.se
d-i mirror/http/directory string /mirror/trisquel/packages
d-i mirror/http/proxy string
d-i partman-auto/method string regular
d-i partman-partitioning/confirm_write_new_label boolean true
d-i partman/choose_partition select finish
d-i partman/confirm boolean true
d-i partman/confirm_nooverwrite boolean true
d-i partman-basicfilesystems/no_swap boolean false
d-i partman-auto/expert_recipe string myroot :: 1000 50 -1 ext4 \
     $primary    $bootable    method  format   \
     format    use_filesystem    filesystem  ext4   \
     mountpoint  /   \
    .
d-i partman-auto/choose_recipe select myroot
d-i passwd/root-login boolean true
d-i user-setup/allow-password-weak boolean true
d-i passwd/root-password password r00tme
d-i passwd/root-password-again password r00tme
d-i passwd/make-user boolean false
tasksel tasksel/first multiselect
d-i pkgsel/include string openssh-server
popularity-contest popularity-contest/participate boolean false
d-i grub-installer/only_debian boolean true
d-i grub-installer/with_other_os boolean true
d-i grub-installer/bootdev string default
d-i finish-install/reboot_in_progress note
d-i preseed/late_command string mkdir /target/root/.ssh ; echo ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAILzCFcHHrKzVSPDDarZPYqn89H5TPaxwcORgRg+4DagE cardno:FFFE67252015 > /target/root/.ssh/authorized_keys
^D
root@trana:~# 
Use the file above as a skeleton for preparing a VM-specific preseed file as follows. The environment variables HOST and IPS will be used later on too.

root@trana:~# HOST=foo
root@trana:~# IP=192.168.10.197
root@trana:~# sed -e "s,get_ipaddress string.*,get_ipaddress string $IP," -e "s,get_hostname string.*,get_hostname string $HOST," < trisquel.preseed > vm-$HOST.preseed
root@trana:~# 
The following script is used to prepare the ISO images with the preseed file that we will need. This script is inspired by the Debian Wiki Preseed EditIso page and the Trisquel ISO customization wiki page. There are a couple of variations based on earlier works. Paths are updated to match the Trisquel netinst ISO layout, which differ slightly from Debian. We modify isolinux.cfg to boot the auto label without a timeout. On Trisquel 11 the auto boot label exists, but on Trisquel 9 and Trisquel 10 it does not exist so we add it in order to be able to start the automated preseed installation.

root@trana:~# cat gen-preseed-iso 
#!/bin/sh
# Copyright (C) 2018-2022 Simon Josefsson -- GPLv3+
# https://wiki.debian.org/DebianInstaller/Preseed/EditIso
# https://trisquel.info/en/wiki/customizing-trisquel-iso
set -e
set -x
ISO="$1"
PRESEED="$2"
OUTISO="$3"
LASTPWD="$PWD"
test -f "$ISO"
test -f "$PRESEED"
test ! -f "$OUTISO"
TMPDIR=$(mktemp -d)
mkdir "$TMPDIR/mnt"
mkdir "$TMPDIR/tmp"
cp "$PRESEED" "$TMPDIR"/preseed.cfg
cd "$TMPDIR"
mount "$ISO" mnt/
cp -rT mnt/ tmp/
umount mnt/
chmod +w -R tmp/
gunzip tmp/initrd.gz
echo preseed.cfg   cpio -H newc -o -A -F tmp/initrd
gzip tmp/initrd
chmod -w -R tmp/
sed -i "s/timeout 0/timeout 1/" tmp/isolinux.cfg
sed -i "s/default vesamenu.c32/default auto/" tmp/isolinux.cfg
if ! grep -q auto tmp/adtxt.cfg; then
    cat<<EOF >> tmp/adtxt.cfg
label auto
	menu label ^Automated install
	kernel linux
	append auto=true priority=critical vga=788 initrd=initrd.gz --- quiet
EOF
fi
cd tmp/
find -follow -type f   xargs md5sum  > md5sum.txt
cd ..
cd "$LASTPWD"
genisoimage -r -J -b isolinux.bin -c boot.cat \
            -no-emul-boot -boot-load-size 4 -boot-info-table \
            -o "$OUTISO" "$TMPDIR/tmp/"
rm -rf "$TMPDIR"
exit 0
^D
root@trana:~# chmod +x gen-preseed-iso 
root@trana:~# 
Next run the command on one of the downloaded ISO image and the generated preseed file.

root@trana:~# ./gen-preseed-iso /root/iso/trisquel-netinst_10.0.1_amd64.iso vm-$HOST.preseed vm-$HOST.iso
+ ISO=/root/iso/trisquel-netinst_10.0.1_amd64.iso
+ PRESEED=vm-foo.preseed
+ OUTISO=vm-foo.iso
+ LASTPWD=/root
+ test -f /root/iso/trisquel-netinst_10.0.1_amd64.iso
+ test -f vm-foo.preseed
+ test ! -f vm-foo.iso
+ mktemp -d
+ TMPDIR=/tmp/tmp.mNEprT4Tx9
+ mkdir /tmp/tmp.mNEprT4Tx9/mnt
+ mkdir /tmp/tmp.mNEprT4Tx9/tmp
+ cp vm-foo.preseed /tmp/tmp.mNEprT4Tx9/preseed.cfg
+ cd /tmp/tmp.mNEprT4Tx9
+ mount /root/iso/trisquel-netinst_10.0.1_amd64.iso mnt/
mount: /tmp/tmp.mNEprT4Tx9/mnt: WARNING: source write-protected, mounted read-only.
+ cp -rT mnt/ tmp/
+ umount mnt/
+ chmod +w -R tmp/
+ gunzip tmp/initrd.gz
+ echo preseed.cfg
+ cpio -H newc -o -A -F tmp/initrd
5 blocks
+ gzip tmp/initrd
+ chmod -w -R tmp/
+ sed -i s/timeout 0/timeout 1/ tmp/isolinux.cfg
+ sed -i s/default vesamenu.c32/default auto/ tmp/isolinux.cfg
+ grep -q auto tmp/adtxt.cfg
+ cat
+ cd tmp/
+ find -follow -type f
+ xargs md5sum
+ cd ..
+ cd /root
+ genisoimage -r -J -b isolinux.bin -c boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -o vm-foo.iso /tmp/tmp.mNEprT4Tx9/tmp/
I: -input-charset not specified, using utf-8 (detected in locale settings)
Using GCRY_000.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/gcry_sha512.mod (gcry_sha256.mod)
Using XNU_U000.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/xnu_uuid.mod (xnu_uuid_test.mod)
Using PASSW000.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/password_pbkdf2.mod (password.mod)
Using PART_000.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/part_sunpc.mod (part_sun.mod)
Using USBSE000.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/usbserial_pl2303.mod (usbserial_ftdi.mod)
Using USBSE001.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/usbserial_ftdi.mod (usbserial_usbdebug.mod)
Using VIDEO000.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/videotest.mod (videotest_checksum.mod)
Using GFXTE000.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/gfxterm_background.mod (gfxterm_menu.mod)
Using GCRY_001.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/gcry_sha256.mod (gcry_sha1.mod)
Using MULTI000.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/multiboot2.mod (multiboot.mod)
Using USBSE002.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/usbserial_usbdebug.mod (usbserial_common.mod)
Using MDRAI000.MOD;1 for  /tmp/tmp.mNEprT4Tx9/tmp/boot/grub/x86_64-efi/mdraid09.mod (mdraid09_be.mod)
Size of boot image is 4 sectors -> No emulation
 22.89% done, estimate finish Thu Dec 29 23:36:18 2022
 45.70% done, estimate finish Thu Dec 29 23:36:18 2022
 68.56% done, estimate finish Thu Dec 29 23:36:18 2022
 91.45% done, estimate finish Thu Dec 29 23:36:18 2022
Total translation table size: 2048
Total rockridge attributes bytes: 24816
Total directory bytes: 40960
Path table size(bytes): 64
Max brk space used 46000
21885 extents written (42 MB)
+ rm -rf /tmp/tmp.mNEprT4Tx9
+ exit 0
root@trana:~#
Now the image is ready for installation, so invoke virt-install as follows. The machine will start directly, launching the preseed automatic installation. At this point, I usually click on the virtual machine in virt-manager to follow screen output until the installation has finished. If everything works OK the machines comes up and I can ssh into it.

root@trana:~# virt-install --name $HOST --disk vm-$HOST.img,size=5 --cdrom vm-$HOST.iso --osinfo linux2020 --autostart --noautoconsole --wait
Using linux2020 default --memory 4096
Starting install...
Allocating 'vm-foo.img'                                                                                                                                     0 B  00:00:00 ... 
Creating domain...                                                                                                                                          0 B  00:00:00     
Domain is still running. Installation may be in progress.
Waiting for the installation to complete.
Domain has shutdown. Continuing.
Domain creation completed.
Restarting guest.
root@trana:~# 
There are some problems that I have noticed that would be nice to fix, but are easy to work around. The first is that at the end of the installation of Trisquel 9 and Trisquel 10, the VM hangs after displaying Sent SIGKILL to all processes followed by Requesting system reboot. I kill the VM manually using virsh destroy foo and start it up again using virsh start foo. For production use I expect to be running Trisquel 11, where the problem doesn t happen, so this does not bother me enough to debug further. The remaining issue that once booted, a Trisquel 11 VM has lost its DNS nameserver configuration, presumably due to poor integration with systemd-resolved. Both Trisquel 9 and Trisquel 10 uses systemd-resolved where DNS works after first boot, so this appears to be a Trisquel 11 bug. You can work around it with rm -f /etc/resolv.conf && echo 'nameserver A.B.C.D' > /etc/resolv.conf or drink the systemd Kool-Aid. If you want to clean up and re-start the process, here is how you wipe out what you did. After this, you may run the sed, ./gen-preseed-iso and virt-install commands again. Remember, use virsh shutdown foo to gracefully shutdown a VM.

root@trana:~# virsh destroy foo
Domain 'foo' destroyed
root@trana:~# virsh undefine foo --remove-all-storage
Domain 'foo' has been undefined
Volume 'vda'(/root/vm-foo.img) removed.
root@trana:~# rm vm-foo.*
root@trana:~# 
Happy hacking on your virtal machines!

12 December 2022

Jonathan McDowell: Setting up FreshRSS in a subdirectory

Ever since the demise of Google Reader I have been looking for a suitable replacement RSS reader. In the past I used to use Liferea but that was when I used a single desktop machine; these days I want to be able to read on my phone and multiple machines. I moved to Feedly and it s been mostly ok, but I m hitting the limit of feeds available in the free tier, and $72/year is a bit more than I can justify to myself. Especially when I have machines already available to me where I could self host something. The problem, of course, is what to host. It seems the best options are all written in PHP, so I had to get over my adverse knee-jerk reaction to that. I ended up on FreshRSS but if it hadn t worked out I d have tried TinyTinyRSS. Of course I m hosting on Debian, and the machine I chose to use was already running nginx and PostgreSQL. So I needed to install PHP:
$ sudo apt install php7.4-fpm php-curl php-gmp php-intl php-mbstring \
	php-pgsql php-xml php-zip
I put my FreshRSS install in /srv/freshrss so I grabbed the 1.20.2 release from GitHub (actually 1.20.1 at the time, but I ve upgraded to the latest since) and untared it in there. I gave www-data access to the data directory (sudo chown -R www-data /srv/freshrss/data) (yes, yes, I could have created a new user specifically for FreshRSS, but I ve chosen not to for now). There s no actual need to configure things up on the filesystem, you can do the initial setup from the web interface. Which is where the trouble came. I ve been an Apache user since 1998 and as a result it s what I know and what I go to. nginx is new to me. And I wanted my FreshRSS instance to live in a subdirectory of an existing TLS-enabled host, rather than have it s own hostname. Now, at least FreshRSS copes with this (unlike far too many other projects), you just have to configure your webserver correctly. Which took me more experimentation than I d like, but I ve ended up with the following snippet:
    # PHP files handling
    location ~ ^/freshrss/.+?\.php(/.*)?$  
        root /srv/freshrss/p;
        fastcgi_pass unix:/run/php/php-fpm.sock;
        fastcgi_split_path_info ^/freshrss(/.+\.php)(/.*)?$;
        set $path_info $fastcgi_path_info;
        fastcgi_param PATH_INFO $path_info;
        include fastcgi_params;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
     
    location ~ ^/freshrss(/.*)?$  
        root /srv/freshrss/p;
        try_files $1 /freshrss$1/index.php$is_args$args;
     
Other than the addition of the freshrss prefix this ends up differing slightly from the FreshRSS webserver configuration example. I ended up having to make the path info on the fastcgi_split_path_info optional, and my try_files in the bare directory location directive needed $is_args$args added or I just ended up in a redirect loop because the session parameters didn t get passed through. I m sure there s a better way to do it, but I did a bunch of searching and this is how I ended up making it work. Before firing up the web configuration I created a suitable database:
$ sudo -Hu postgres psql
psql (13.8 (Debian 13.8-0+deb11u1))
Type "help" for help.
postgres=# create database freshrss;
CREATE DATABASE
postgres=# create user freshrss with encrypted password 'hunter2';
CREATE ROLE
postgres=# grant all privileges on database freshrss to freshrss;
GRANT
postgres=# \q
I ran through the local configuration, creating myself a user and adding some feeds, then created a cronjob to fetch updates hourly and keep a log:
# mkdir /var/log/freshrss
# chown :www-data /var/log/freshrss
# chmod 775 /var/log/freshrss
# cat > /etc/cron.d/freshrss-refresh <EOF
33 * * * * www-data /srv/freshrss/app/actualize_script.php > /var/log/freshrss/update-$(date --iso-8601=minutes).log 2>&1
EOF
Experiences so far? Reasonably happy. The interface seems snappy enough, and works well both on mobile and desktop. I m only running a single user instance at present, but am considering opening it up to some other folk and will see how that scales. And it clearly indicated a number of my feeds that were broken, so I ve cleaned some up that are still around and deleted the missing ones. Now I just need to figure out what else I should be subscribed to that I ve been putting off due to the Feedly limit!

10 December 2022

Simon Josefsson: How to complicate buying a laptop

I m about to migrate to a new laptop, having done a brief pre-purchase review of options on Fosstodon and reaching a decision to buy the NovaCustom NV41. Given the rapid launch and decline of Mastodon instances, I thought I d better summarize my process and conclusion on my self-hosted blog until the fediverse self-hosting situation improves. Since 2010 my main portable computing device has been the Lenovo X201 that replaced the Dell Precision M65 that I bought in 2006. I have been incredibly happy with the X201, even to the point that in 2015 when I wanted to find a replacement, I couldn t settle on a decision and eventually realized I couldn t articulate what was wrong with the X201 and decided to just buy another X201 second-hand for my second office. There is still no deal-breaker with the X201, and I m doing most of my computing on it including writing this post. However, today I can better articulate what is lacking with the X201 that I desire, and the state of the available options on the market has improved since my last attempt in 2015. Briefly, my desired properties are: My workload for the machine is Emacs, Firefox, Nextcloud client, GNOME, Evolution (mail & calendar), LibreOffice Calc/Writer, compiling software and some podman/qemu for testing. I have used Debian as the main operating system for the entire life of this laptop, but have experimented with PureOS recently. My current X201 is useful enough for this, although support for 4K displays and a faster machine wouldn t hurt. Based on my experience in 2015 that led me to make no decision, I changed perspective. This is a judgement call and I will not be able to fulfil all criteria. I will have to decide on a balance and the final choice will include elements that I really dislike, but still it will hopefully be better than nothing. The conflict for me mainly center around these parts: A simple choice for me would be to buy one of the FSF RYF certified laptops. Right now that list only contains the 10+ year old Lenovo series, and I actually already have a X200 with libreboot that I bought earlier for comparison. The reason the X200 didn t work out as a replacement for me was the lack of a mouse trackpad, concerns about non-free EC firmware, Intel ME uncertainty (is it really neutralized?) and non-free CPU microcode (what are the bugs that it fixes?), but primarily that for some reason that I can t fully articulate it feels weird to use a laptop manufactured by Lenovo but modified by third parties to be useful. I believe in market forces to pressure manufacturers into Doing The Right Thing, and feel that there is no incentive for Lenovo to use libreboot in the future when this market niche is already fulfilled by re-sellers modifying Lenovo laptops. So I d be happier buying a laptop from someone who is natively supportive of they way I m computing. I m sure this aspect could be discussed a lot more, and maybe I ll come back to do that, and could even reconsider my thinking (the right-to-repair argument is compelling). I will definitely continue to monitor the list of RYF-certified laptops to see if future entries are more suitable options for me. Eventually I decided to buy the NovaCustom NV41 laptop, and it arrived quickly and I m in the process of setting it up. I hope to write a separate blog about it next.

16 November 2022

Antoine Beaupr : A ZFS migration

In my tubman setup, I started using ZFS on an old server I had lying around. The machine is really old though (2011!) and it "feels" pretty slow. I want to see how much of that is ZFS and how much is the machine. Synthetic benchmarks show that ZFS may be slower than mdadm in RAID-10 or RAID-6 configuration, so I want to confirm that on a live workload: my workstation. Plus, I want easy, regular, high performance backups (with send/receive snapshots) and there's no way I'm going to use BTRFS because I find it too confusing and unreliable. So off we go.

Installation Since this is a conversion (and not a new install), our procedure is slightly different than the official documentation but otherwise it's pretty much in the same spirit: we're going to use ZFS for everything, including the root filesystem. So, install the required packages, on the current system:
apt install --yes gdisk zfs-dkms zfs zfs-initramfs zfsutils-linux
We also tell DKMS that we need to rebuild the initrd when upgrading:
echo REMAKE_INITRD=yes > /etc/dkms/zfs.conf

Partitioning This is going to partition /dev/sdc with:
  • 1MB MBR / BIOS legacy boot
  • 512MB EFI boot
  • 1GB bpool, unencrypted pool for /boot
  • rest of the disk for zpool, the rest of the data
     sgdisk --zap-all /dev/sdc
     sgdisk -a1 -n1:24K:+1000K -t1:EF02 /dev/sdc
     sgdisk     -n2:1M:+512M   -t2:EF00 /dev/sdc
     sgdisk     -n3:0:+1G      -t3:BF01 /dev/sdc
     sgdisk     -n4:0:0        -t4:BF00 /dev/sdc
    
That will look something like this:
    root@curie:/home/anarcat# sgdisk -p /dev/sdc
    Disk /dev/sdc: 1953525168 sectors, 931.5 GiB
    Model: ESD-S1C         
    Sector size (logical/physical): 512/512 bytes
    Disk identifier (GUID): [REDACTED]
    Partition table holds up to 128 entries
    Main partition table begins at sector 2 and ends at sector 33
    First usable sector is 34, last usable sector is 1953525134
    Partitions will be aligned on 16-sector boundaries
    Total free space is 14 sectors (7.0 KiB)
    Number  Start (sector)    End (sector)  Size       Code  Name
       1              48            2047   1000.0 KiB  EF02  
       2            2048         1050623   512.0 MiB   EF00  
       3         1050624         3147775   1024.0 MiB  BF01  
       4         3147776      1953525134   930.0 GiB   BF00
Unfortunately, we can't be sure of the sector size here, because the USB controller is probably lying to us about it. Normally, this smartctl command should tell us the sector size as well:
root@curie:~# smartctl -i /dev/sdb -qnoserial
smartctl 7.2 2020-12-30 r5155 [x86_64-linux-5.10.0-14-amd64] (local build)
Copyright (C) 2002-20, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF INFORMATION SECTION ===
Model Family:     Western Digital Black Mobile
Device Model:     WDC WD10JPLX-00MBPT0
Firmware Version: 01.01H01
User Capacity:    1 000 204 886 016 bytes [1,00 TB]
Sector Sizes:     512 bytes logical, 4096 bytes physical
Rotation Rate:    7200 rpm
Form Factor:      2.5 inches
Device is:        In smartctl database [for details use: -P show]
ATA Version is:   ATA8-ACS T13/1699-D revision 6
SATA Version is:  SATA 3.0, 6.0 Gb/s (current: 6.0 Gb/s)
Local Time is:    Tue May 17 13:33:04 2022 EDT
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
Above is the example of the builtin HDD drive. But the SSD device enclosed in that USB controller doesn't support SMART commands, so we can't trust that it really has 512 bytes sectors. This matters because we need to tweak the ashift value correctly. We're going to go ahead the SSD drive has the common 4KB settings, which means ashift=12. Note here that we are not creating a separate partition for swap. Swap on ZFS volumes (AKA "swap on ZVOL") can trigger lockups and that issue is still not fixed upstream. Ubuntu recommends using a separate partition for swap instead. But since this is "just" a workstation, we're betting that we will not suffer from this problem, after hearing a report from another Debian developer running this setup on their workstation successfully. We do not recommend this setup though. In fact, if I were to redo this partition scheme, I would probably use LUKS encryption and setup a dedicated swap partition, as I had problems with ZFS encryption as well.

Creating pools ZFS pools are somewhat like "volume groups" if you are familiar with LVM, except they obviously also do things like RAID-10. (Even though LVM can technically also do RAID, people typically use mdadm instead.) In any case, the guide suggests creating two different pools here: one, in cleartext, for boot, and a separate, encrypted one, for the rest. Technically, the boot partition is required because the Grub bootloader only supports readonly ZFS pools, from what I understand. But I'm a little out of my depth here and just following the guide.

Boot pool creation This creates the boot pool in readonly mode with features that grub supports:
    zpool create \
        -o cachefile=/etc/zfs/zpool.cache \
        -o ashift=12 -d \
        -o feature@async_destroy=enabled \
        -o feature@bookmarks=enabled \
        -o feature@embedded_data=enabled \
        -o feature@empty_bpobj=enabled \
        -o feature@enabled_txg=enabled \
        -o feature@extensible_dataset=enabled \
        -o feature@filesystem_limits=enabled \
        -o feature@hole_birth=enabled \
        -o feature@large_blocks=enabled \
        -o feature@lz4_compress=enabled \
        -o feature@spacemap_histogram=enabled \
        -o feature@zpool_checkpoint=enabled \
        -O acltype=posixacl -O canmount=off \
        -O compression=lz4 \
        -O devices=off -O normalization=formD -O relatime=on -O xattr=sa \
        -O mountpoint=/boot -R /mnt \
        bpool /dev/sdc3
I haven't investigated all those settings and just trust the upstream guide on the above.

Main pool creation This is a more typical pool creation.
    zpool create \
        -o ashift=12 \
        -O encryption=on -O keylocation=prompt -O keyformat=passphrase \
        -O acltype=posixacl -O xattr=sa -O dnodesize=auto \
        -O compression=zstd \
        -O relatime=on \
        -O canmount=off \
        -O mountpoint=/ -R /mnt \
        rpool /dev/sdc4
Breaking this down:
  • -o ashift=12: mentioned above, 4k sector size
  • -O encryption=on -O keylocation=prompt -O keyformat=passphrase: encryption, prompt for a password, default algorithm is aes-256-gcm, explicit in the guide, made implicit here
  • -O acltype=posixacl -O xattr=sa: enable ACLs, with better performance (not enabled by default)
  • -O dnodesize=auto: related to extended attributes, less compatibility with other implementations
  • -O compression=zstd: enable zstd compression, can be disabled/enabled by dataset to with zfs set compression=off rpool/example
  • -O relatime=on: classic atime optimisation, another that could be used on a busy server is atime=off
  • -O canmount=off: do not make the pool mount automatically with mount -a?
  • -O mountpoint=/ -R /mnt: mount pool on / in the future, but /mnt for now
Those settings are all available in zfsprops(8). Other flags are defined in zpool-create(8). The reasoning behind them is also explained in the upstream guide and some also in [the Debian wiki][]. Those flags were actually not used:
  • -O normalization=formD: normalize file names on comparisons (not storage), implies utf8only=on, which is a bad idea (and effectively meant my first sync failed to copy some files, including this folder from a supysonic checkout). and this cannot be changed after the filesystem is created. bad, bad, bad.
[the Debian wiki]: https://wiki.debian.org/ZFS#Advanced_Topics

Side note about single-disk pools Also note that we're living dangerously here: single-disk ZFS pools are rumoured to be more dangerous than not running ZFS at all. The choice quote from this article is:
[...] any error can be detected, but cannot be corrected. This sounds like an acceptable compromise, but its actually not. The reason its not is that ZFS' metadata cannot be allowed to be corrupted. If it is it is likely the zpool will be impossible to mount (and will probably crash the system once the corruption is found). So a couple of bad sectors in the right place will mean that all data on the zpool will be lost. Not some, all. Also there's no ZFS recovery tools, so you cannot recover any data on the drives.
Compared with (say) ext4, where a single disk error can recovered, this is pretty bad. But we are ready to live with this with the idea that we'll have hourly offline snapshots that we can easily recover from. It's trade-off. Also, we're running this on a NVMe/M.2 drive which typically just blinks out of existence completely, and doesn't "bit rot" the way a HDD would. Also, the FreeBSD handbook quick start doesn't have any warnings about their first example, which is with a single disk. So I am reassured at least.

Creating mount points Next we create the actual filesystems, known as "datasets" which are the things that get mounted on mountpoint and hold the actual files.
  • this creates two containers, for ROOT and BOOT
     zfs create -o canmount=off -o mountpoint=none rpool/ROOT &&
     zfs create -o canmount=off -o mountpoint=none bpool/BOOT
    
    Note that it's unclear to me why those datasets are necessary, but they seem common practice, also used in this FreeBSD example. The OpenZFS guide mentions the Solaris upgrades and Ubuntu's zsys that use that container for upgrades and rollbacks. This blog post seems to explain a bit the layout behind the installer.
  • this creates the actual boot and root filesystems:
     zfs create -o canmount=noauto -o mountpoint=/ rpool/ROOT/debian &&
     zfs mount rpool/ROOT/debian &&
     zfs create -o mountpoint=/boot bpool/BOOT/debian
    
    I guess the debian name here is because we could technically have multiple operating systems with the same underlying datasets.
  • then the main datasets:
     zfs create                                 rpool/home &&
     zfs create -o mountpoint=/root             rpool/home/root &&
     chmod 700 /mnt/root &&
     zfs create                                 rpool/var
    
  • exclude temporary files from snapshots:
     zfs create -o com.sun:auto-snapshot=false  rpool/var/cache &&
     zfs create -o com.sun:auto-snapshot=false  rpool/var/tmp &&
     chmod 1777 /mnt/var/tmp
    
  • and skip automatic snapshots in Docker:
     zfs create -o canmount=off                 rpool/var/lib &&
     zfs create -o com.sun:auto-snapshot=false  rpool/var/lib/docker
    
    Notice here a peculiarity: we must create rpool/var/lib to create rpool/var/lib/docker otherwise we get this error:
     cannot create 'rpool/var/lib/docker': parent does not exist
    
    ... and no, just creating /mnt/var/lib doesn't fix that problem. In fact, it makes things even more confusing because an existing directory shadows a mountpoint, which is the opposite of how things normally work. Also note that you will probably need to change storage driver in Docker, see the zfs-driver documentation for details but, basically, I did:
    echo '  "storage-driver": "zfs"  ' > /etc/docker/daemon.json
    
    Note that podman has the same problem (and similar solution):
    printf '[storage]\ndriver = "zfs"\n' > /etc/containers/storage.conf
    
  • make a tmpfs for /run:
     mkdir /mnt/run &&
     mount -t tmpfs tmpfs /mnt/run &&
     mkdir /mnt/run/lock
    
We don't create a /srv, as that's the HDD stuff. Also mount the EFI partition:
mkfs.fat -F 32 /dev/sdc2 &&
mount /dev/sdc2 /mnt/boot/efi/
At this point, everything should be mounted in /mnt. It should look like this:
root@curie:~# LANG=C df -h -t zfs -t vfat
Filesystem            Size  Used Avail Use% Mounted on
rpool/ROOT/debian     899G  384K  899G   1% /mnt
bpool/BOOT/debian     832M  123M  709M  15% /mnt/boot
rpool/home            899G  256K  899G   1% /mnt/home
rpool/home/root       899G  256K  899G   1% /mnt/root
rpool/var             899G  384K  899G   1% /mnt/var
rpool/var/cache       899G  256K  899G   1% /mnt/var/cache
rpool/var/tmp         899G  256K  899G   1% /mnt/var/tmp
rpool/var/lib/docker  899G  256K  899G   1% /mnt/var/lib/docker
/dev/sdc2             511M  4.0K  511M   1% /mnt/boot/efi
Now that we have everything setup and mounted, let's copy all files over.

Copying files This is a list of all the mounted filesystems
for fs in /boot/ /boot/efi/ / /home/; do
    echo "syncing $fs to /mnt$fs..." && 
    rsync -aSHAXx --info=progress2 --delete $fs /mnt$fs
done
You can check that the list is correct with:
mount -l -t ext4,btrfs,vfat   awk ' print $3 '
Note that we skip /srv as it's on a different disk. On the first run, we had:
root@curie:~# for fs in /boot/ /boot/efi/ / /home/; do
        echo "syncing $fs to /mnt$fs..." && 
        rsync -aSHAXx --info=progress2 $fs /mnt$fs
    done
syncing /boot/ to /mnt/boot/...
              0   0%    0.00kB/s    0:00:00 (xfr#0, to-chk=0/299)  
syncing /boot/efi/ to /mnt/boot/efi/...
     16,831,437 100%  184.14MB/s    0:00:00 (xfr#101, to-chk=0/110)
syncing / to /mnt/...
 28,019,293,280  94%   47.63MB/s    0:09:21 (xfr#703710, ir-chk=6748/839220)rsync: [generator] delete_file: rmdir(var/lib/docker) failed: Device or resource busy (16)
could not make way for new symlink: var/lib/docker
 34,081,267,990  98%   50.71MB/s    0:10:40 (xfr#736577, to-chk=0/867732)    
rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1333) [sender=3.2.3]
syncing /home/ to /mnt/home/...
rsync: [sender] readlink_stat("/home/anarcat/.fuse") failed: Permission denied (13)
 24,456,268,098  98%   68.03MB/s    0:05:42 (xfr#159867, ir-chk=6875/172377) 
file has vanished: "/home/anarcat/.cache/mozilla/firefox/s2hwvqbu.quantum/cache2/entries/B3AB0CDA9C4454B3C1197E5A22669DF8EE849D90"
199,762,528,125  93%   74.82MB/s    0:42:26 (xfr#1437846, ir-chk=1018/1983979)rsync: [generator] recv_generator: mkdir "/mnt/home/anarcat/dist/supysonic/tests/assets/\#346" failed: Invalid or incomplete multibyte or wide character (84)
*** Skipping any contents from this failed directory ***
315,384,723,978  96%   76.82MB/s    1:05:15 (xfr#2256473, to-chk=0/2993950)    
rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1333) [sender=3.2.3]
Note the failure to transfer that supysonic file? It turns out they had a weird filename in their source tree, since then removed, but still it showed how the utf8only feature might not be such a bad idea. At this point, the procedure was restarted all the way back to "Creating pools", after unmounting all ZFS filesystems (umount /mnt/run /mnt/boot/efi && umount -t zfs -a) and destroying the pool, which, surprisingly, doesn't require any confirmation (zpool destroy rpool). The second run was cleaner:
root@curie:~# for fs in /boot/ /boot/efi/ / /home/; do
        echo "syncing $fs to /mnt$fs..." && 
        rsync -aSHAXx --info=progress2 --delete $fs /mnt$fs
    done
syncing /boot/ to /mnt/boot/...
              0   0%    0.00kB/s    0:00:00 (xfr#0, to-chk=0/299)  
syncing /boot/efi/ to /mnt/boot/efi/...
              0   0%    0.00kB/s    0:00:00 (xfr#0, to-chk=0/110)  
syncing / to /mnt/...
 28,019,033,070  97%   42.03MB/s    0:10:35 (xfr#703671, ir-chk=1093/833515)rsync: [generator] delete_file: rmdir(var/lib/docker) failed: Device or resource busy (16)
could not make way for new symlink: var/lib/docker
 34,081,807,102  98%   44.84MB/s    0:12:04 (xfr#736580, to-chk=0/867723)    
rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1333) [sender=3.2.3]
syncing /home/ to /mnt/home/...
rsync: [sender] readlink_stat("/home/anarcat/.fuse") failed: Permission denied (13)
IO error encountered -- skipping file deletion
 24,043,086,450  96%   62.03MB/s    0:06:09 (xfr#151819, ir-chk=15117/172571)
file has vanished: "/home/anarcat/.cache/mozilla/firefox/s2hwvqbu.quantum/cache2/entries/4C1FDBFEA976FF924D062FB990B24B897A77B84B"
315,423,626,507  96%   67.09MB/s    1:14:43 (xfr#2256845, to-chk=0/2994364)    
rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1333) [sender=3.2.3]
Also note the transfer speed: we seem capped at 76MB/s, or 608Mbit/s. This is not as fast as I was expecting: the USB connection seems to be at around 5Gbps:
anarcat@curie:~$ lsusb -tv   head -4
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 5000M
    ID 1d6b:0003 Linux Foundation 3.0 root hub
     __ Port 1: Dev 4, If 0, Class=Mass Storage, Driver=uas, 5000M
        ID 0b05:1932 ASUSTek Computer, Inc.
So it shouldn't cap at that speed. It's possible the USB adapter is failing to give me the full speed though. It's not the M.2 SSD drive either, as that has a ~500MB/s bandwidth, acccording to its spec. At this point, we're about ready to do the final configuration. We drop to single user mode and do the rest of the procedure. That used to be shutdown now, but it seems like the systemd switch broke that, so now you can reboot into grub and pick the "recovery" option. Alternatively, you might try systemctl rescue, as I found out. I also wanted to copy the drive over to another new NVMe drive, but that failed: it looks like the USB controller I have doesn't work with older, non-NVME drives.

Boot configuration Now we need to enter the new system to rebuild the boot loader and initrd and so on. First, we bind mounts and chroot into the ZFS disk:
mount --rbind /dev  /mnt/dev &&
mount --rbind /proc /mnt/proc &&
mount --rbind /sys  /mnt/sys &&
chroot /mnt /bin/bash
Next we add an extra service that imports the bpool on boot, to make sure it survives a zpool.cache destruction:
cat > /etc/systemd/system/zfs-import-bpool.service <<EOF
[Unit]
DefaultDependencies=no
Before=zfs-import-scan.service
Before=zfs-import-cache.service
[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/sbin/zpool import -N -o cachefile=none bpool
# Work-around to preserve zpool cache:
ExecStartPre=-/bin/mv /etc/zfs/zpool.cache /etc/zfs/preboot_zpool.cache
ExecStartPost=-/bin/mv /etc/zfs/preboot_zpool.cache /etc/zfs/zpool.cache
[Install]
WantedBy=zfs-import.target
EOF
Enable the service:
systemctl enable zfs-import-bpool.service
I had to trim down /etc/fstab and /etc/crypttab to only contain references to the legacy filesystems (/srv is still BTRFS!). If we don't already have a tmpfs defined in /etc/fstab:
ln -s /usr/share/systemd/tmp.mount /etc/systemd/system/ &&
systemctl enable tmp.mount
Rebuild boot loader with support for ZFS, but also to workaround GRUB's missing zpool-features support:
grub-probe /boot   grep -q zfs &&
update-initramfs -c -k all &&
sed -i 's,GRUB_CMDLINE_LINUX.*,GRUB_CMDLINE_LINUX="root=ZFS=rpool/ROOT/debian",' /etc/default/grub &&
update-grub
For good measure, make sure the right disk is configured here, for example you might want to tag both drives in a RAID array:
dpkg-reconfigure grub-pc
Install grub to EFI while you're there:
grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=debian --recheck --no-floppy
Filesystem mount ordering. The rationale here in the OpenZFS guide is a little strange, but I don't dare ignore that.
mkdir /etc/zfs/zfs-list.cache
touch /etc/zfs/zfs-list.cache/bpool
touch /etc/zfs/zfs-list.cache/rpool
zed -F &
Verify that zed updated the cache by making sure these are not empty:
cat /etc/zfs/zfs-list.cache/bpool
cat /etc/zfs/zfs-list.cache/rpool
Once the files have data, stop zed:
fg
Press Ctrl-C.
Fix the paths to eliminate /mnt:
sed -Ei "s /mnt/? / " /etc/zfs/zfs-list.cache/*
Snapshot initial install:
zfs snapshot bpool/BOOT/debian@install
zfs snapshot rpool/ROOT/debian@install
Exit chroot:
exit

Finalizing One last sync was done in rescue mode:
for fs in /boot/ /boot/efi/ / /home/; do
    echo "syncing $fs to /mnt$fs..." && 
    rsync -aSHAXx --info=progress2 --delete $fs /mnt$fs
done
Then we unmount all filesystems:
mount   grep -v zfs   tac   awk '/\/mnt/  print $3 '   xargs -i  umount -lf  
zpool export -a
Reboot, swap the drives, and boot in ZFS. Hurray!

Benchmarks This is a test that was ran in single-user mode using fio and the Ars Technica recommended tests, which are:
  • Single 4KiB random write process:
     fio --name=randwrite4k1x --ioengine=posixaio --rw=randwrite --bs=4k --size=4g --numjobs=1 --iodepth=1 --runtime=60 --time_based --end_fsync=1
    
  • 16 parallel 64KiB random write processes:
     fio --name=randwrite64k16x --ioengine=posixaio --rw=randwrite --bs=64k --size=256m --numjobs=16 --iodepth=16 --runtime=60 --time_based --end_fsync=1
    
  • Single 1MiB random write process:
     fio --name=randwrite1m1x --ioengine=posixaio --rw=randwrite --bs=1m --size=16g --numjobs=1 --iodepth=1 --runtime=60 --time_based --end_fsync=1
    
Strangely, that's not exactly what the author, Jim Salter, did in his actual test bench used in the ZFS benchmarking article. The first thing is there's no read test at all, which is already pretty strange. But also it doesn't include stuff like dropping caches or repeating results. So here's my variation, which i called fio-ars-bench.sh for now. It just batches a bunch of fio tests, one by one, 60 seconds each. It should take about 12 minutes to run, as there are 3 pair of tests, read/write, with and without async. My bias, before building, running and analysing those results is that ZFS should outperform the traditional stack on writes, but possibly not on reads. It's also possible it outperforms it on both, because it's a newer drive. A new test might be possible with a new external USB drive as well, although I doubt I will find the time to do this.

Results All tests were done on WD blue SN550 drives, which claims to be able to push 2400MB/s read and 1750MB/s write. An extra drive was bought to move the LVM setup from a WDC WDS500G1B0B-00AS40 SSD, a WD blue M.2 2280 SSD that was at least 5 years old, spec'd at 560MB/s read, 530MB/s write. Benchmarks were done on the M.2 SSD drive but discarded so that the drive difference is not a factor in the test. In practice, I'm going to assume we'll never reach those numbers because we're not actually NVMe (this is an old workstation!) so the bottleneck isn't the disk itself. For our purposes, it might still give us useful results.

Rescue test, LUKS/LVM/ext4 Those tests were performed with everything shutdown, after either entering the system in rescue mode, or by reaching that target with:
systemctl rescue
The network might have been started before or after the test as well:
systemctl start systemd-networkd
So it should be fairly reliable as basically nothing else is running. Raw numbers, from the ?job-curie-lvm.log, converted to MiB/s and manually merged:
test read I/O read IOPS write I/O write IOPS
rand4k4g1x 39.27 10052 212.15 54310
rand4k4g1x--fsync=1 39.29 10057 2.73 699
rand64k256m16x 1297.00 20751 1068.57 17097
rand64k256m16x--fsync=1 1290.90 20654 353.82 5661
rand1m16g1x 315.15 315 563.77 563
rand1m16g1x--fsync=1 345.88 345 157.01 157
Peaks are at about 20k IOPS and ~1.3GiB/s read, 1GiB/s write in the 64KB blocks with 16 jobs. Slowest is the random 4k block sync write at an abysmal 3MB/s and 700 IOPS The 1MB read/write tests have lower IOPS, but that is expected.

Rescue test, ZFS This test was also performed in rescue mode. Raw numbers, from the ?job-curie-zfs.log, converted to MiB/s and manually merged:
test read I/O read IOPS write I/O write IOPS
rand4k4g1x 77.20 19763 27.13 6944
rand4k4g1x--fsync=1 76.16 19495 6.53 1673
rand64k256m16x 1882.40 30118 70.58 1129
rand64k256m16x--fsync=1 1865.13 29842 71.98 1151
rand1m16g1x 921.62 921 102.21 102
rand1m16g1x--fsync=1 908.37 908 64.30 64
Peaks are at 1.8GiB/s read, also in the 64k job like above, but much faster. The write is, as expected, much slower at 70MiB/s (compared to 1GiB/s!), but it should be noted the sync write doesn't degrade performance compared to async writes (although it's still below the LVM 300MB/s).

Conclusions Really, ZFS has trouble performing in all write conditions. The random 4k sync write test is the only place where ZFS outperforms LVM in writes, and barely (7MiB/s vs 3MiB/s). Everywhere else, writes are much slower, sometimes by an order of magnitude. And before some ZFS zealot jumps in talking about the SLOG or some other cache that could be added to improved performance, I'll remind you that those numbers are on a bare bones NVMe drive, pretty much as fast storage as you can find on this machine. Adding another NVMe drive as a cache probably will not improve write performance here. Still, those are very different results than the tests performed by Salter which shows ZFS beating traditional configurations in all categories but uncached 4k reads (not writes!). That said, those tests are very different from the tests I performed here, where I test writes on a single disk, not a RAID array, which might explain the discrepancy. Also, note that neither LVM or ZFS manage to reach the 2400MB/s read and 1750MB/s write performance specification. ZFS does manage to reach 82% of the read performance (1973MB/s) and LVM 64% of the write performance (1120MB/s). LVM hits 57% of the read performance and ZFS hits barely 6% of the write performance. Overall, I'm a bit disappointed in the ZFS write performance here, I must say. Maybe I need to tweak the record size or some other ZFS voodoo, but I'll note that I didn't have to do any such configuration on the other side to kick ZFS in the pants...

Real world experience This section document not synthetic backups, but actual real world workloads, comparing before and after I switched my workstation to ZFS.

Docker performance I had the feeling that running some git hook (which was firing a Docker container) was "slower" somehow. It seems that, at runtime, ZFS backends are significant slower than their overlayfs/ext4 equivalent:
May 16 14:42:52 curie systemd[1]: home-docker-overlay2-17e4d24228decc2d2d493efc401dbfb7ac29739da0e46775e122078d9daf3e87\x2dinit-merged.mount: Succeeded.
May 16 14:42:52 curie systemd[5161]: home-docker-overlay2-17e4d24228decc2d2d493efc401dbfb7ac29739da0e46775e122078d9daf3e87\x2dinit-merged.mount: Succeeded.
May 16 14:42:52 curie systemd[1]: home-docker-overlay2-17e4d24228decc2d2d493efc401dbfb7ac29739da0e46775e122078d9daf3e87-merged.mount: Succeeded.
May 16 14:42:53 curie dockerd[1723]: time="2022-05-16T14:42:53.087219426-04:00" level=info msg="starting signal loop" namespace=moby path=/run/docker/containerd/daemon/io.containerd.runtime.v2.task/moby/af22586fba07014a4d10ab19da10cf280db7a43cad804d6c1e9f2682f12b5f10 pid=151170
May 16 14:42:53 curie systemd[1]: Started libcontainer container af22586fba07014a4d10ab19da10cf280db7a43cad804d6c1e9f2682f12b5f10.
May 16 14:42:54 curie systemd[1]: docker-af22586fba07014a4d10ab19da10cf280db7a43cad804d6c1e9f2682f12b5f10.scope: Succeeded.
May 16 14:42:54 curie dockerd[1723]: time="2022-05-16T14:42:54.047297800-04:00" level=info msg="shim disconnected" id=af22586fba07014a4d10ab19da10cf280db7a43cad804d6c1e9f2682f12b5f10
May 16 14:42:54 curie dockerd[998]: time="2022-05-16T14:42:54.051365015-04:00" level=info msg="ignoring event" container=af22586fba07014a4d10ab19da10cf280db7a43cad804d6c1e9f2682f12b5f10 module=libcontainerd namespace=moby topic=/tasks/delete type="*events.TaskDelete"
May 16 14:42:54 curie systemd[2444]: run-docker-netns-f5453c87c879.mount: Succeeded.
May 16 14:42:54 curie systemd[5161]: run-docker-netns-f5453c87c879.mount: Succeeded.
May 16 14:42:54 curie systemd[2444]: home-docker-overlay2-17e4d24228decc2d2d493efc401dbfb7ac29739da0e46775e122078d9daf3e87-merged.mount: Succeeded.
May 16 14:42:54 curie systemd[5161]: home-docker-overlay2-17e4d24228decc2d2d493efc401dbfb7ac29739da0e46775e122078d9daf3e87-merged.mount: Succeeded.
May 16 14:42:54 curie systemd[1]: run-docker-netns-f5453c87c879.mount: Succeeded.
May 16 14:42:54 curie systemd[1]: home-docker-overlay2-17e4d24228decc2d2d493efc401dbfb7ac29739da0e46775e122078d9daf3e87-merged.mount: Succeeded.
Translating this:
  • container setup: ~1 second
  • container runtime: ~1 second
  • container teardown: ~1 second
  • total runtime: 2-3 seconds
Obviously, those timestamps are not quite accurate enough to make precise measurements... After I switched to ZFS:
mai 30 15:31:39 curie systemd[1]: var-lib-docker-zfs-graph-41ce08fb7a1d3a9c101694b82722f5621c0b4819bd1d9f070933fd1e00543cdf\x2dinit.mount: Succeeded. 
mai 30 15:31:39 curie systemd[5287]: var-lib-docker-zfs-graph-41ce08fb7a1d3a9c101694b82722f5621c0b4819bd1d9f070933fd1e00543cdf\x2dinit.mount: Succeeded. 
mai 30 15:31:40 curie systemd[1]: var-lib-docker-zfs-graph-41ce08fb7a1d3a9c101694b82722f5621c0b4819bd1d9f070933fd1e00543cdf.mount: Succeeded. 
mai 30 15:31:40 curie systemd[5287]: var-lib-docker-zfs-graph-41ce08fb7a1d3a9c101694b82722f5621c0b4819bd1d9f070933fd1e00543cdf.mount: Succeeded. 
mai 30 15:31:41 curie dockerd[3199]: time="2022-05-30T15:31:41.551403693-04:00" level=info msg="starting signal loop" namespace=moby path=/run/docker/containerd/daemon/io.containerd.runtime.v2.task/moby/42a1a1ed5912a7227148e997f442e7ab2e5cc3558aa3471548223c5888c9b142 pid=141080 
mai 30 15:31:41 curie systemd[1]: run-docker-runtime\x2drunc-moby-42a1a1ed5912a7227148e997f442e7ab2e5cc3558aa3471548223c5888c9b142-runc.ZVcjvl.mount: Succeeded. 
mai 30 15:31:41 curie systemd[5287]: run-docker-runtime\x2drunc-moby-42a1a1ed5912a7227148e997f442e7ab2e5cc3558aa3471548223c5888c9b142-runc.ZVcjvl.mount: Succeeded. 
mai 30 15:31:41 curie systemd[1]: Started libcontainer container 42a1a1ed5912a7227148e997f442e7ab2e5cc3558aa3471548223c5888c9b142. 
mai 30 15:31:45 curie systemd[1]: docker-42a1a1ed5912a7227148e997f442e7ab2e5cc3558aa3471548223c5888c9b142.scope: Succeeded. 
mai 30 15:31:45 curie dockerd[3199]: time="2022-05-30T15:31:45.883019128-04:00" level=info msg="shim disconnected" id=42a1a1ed5912a7227148e997f442e7ab2e5cc3558aa3471548223c5888c9b142 
mai 30 15:31:45 curie dockerd[1726]: time="2022-05-30T15:31:45.883064491-04:00" level=info msg="ignoring event" container=42a1a1ed5912a7227148e997f442e7ab2e5cc3558aa3471548223c5888c9b142 module=libcontainerd namespace=moby topic=/tasks/delete type="*events.TaskDelete" 
mai 30 15:31:45 curie systemd[1]: run-docker-netns-e45f5cf5f465.mount: Succeeded. 
mai 30 15:31:45 curie systemd[5287]: run-docker-netns-e45f5cf5f465.mount: Succeeded. 
mai 30 15:31:45 curie systemd[1]: var-lib-docker-zfs-graph-41ce08fb7a1d3a9c101694b82722f5621c0b4819bd1d9f070933fd1e00543cdf.mount: Succeeded. 
mai 30 15:31:45 curie systemd[5287]: var-lib-docker-zfs-graph-41ce08fb7a1d3a9c101694b82722f5621c0b4819bd1d9f070933fd1e00543cdf.mount: Succeeded.
That's double or triple the run time, from 2 seconds to 6 seconds. Most of the time is spent in run time, inside the container. Here's the breakdown:
  • container setup: ~2 seconds
  • container run: ~4 seconds
  • container teardown: ~1 second
  • total run time: about ~6-7 seconds
That's a two- to three-fold increase! Clearly something is going on here that I should tweak. It's possible that code path is less optimized in Docker. I also worry about podman, but apparently it also supports ZFS backends. Possibly it would perform better, but at this stage I wouldn't have a good comparison: maybe it would have performed better on non-ZFS as well...

Interactivity While doing the offsite backups (below), the system became somewhat "sluggish". I felt everything was slow, and I estimate it introduced ~50ms latency in any input device. Arguably, those are all USB and the external drive was connected through USB, but I suspect the ZFS drivers are not as well tuned with the scheduler as the regular filesystem drivers...

Recovery procedures For test purposes, I unmounted all systems during the procedure:
umount /mnt/boot/efi /mnt/boot/run
umount -a -t zfs
zpool export -a
And disconnected the drive, to see how I would recover this system from another Linux system in case of a total motherboard failure. To import an existing pool, plug the device, then import the pool with an alternate root, so it doesn't mount over your existing filesystems, then you mount the root filesystem and all the others:
zpool import -l -a -R /mnt &&
zfs mount rpool/ROOT/debian &&
zfs mount -a &&
mount /dev/sdc2 /mnt/boot/efi &&
mount -t tmpfs tmpfs /mnt/run &&
mkdir /mnt/run/lock

Offsite backup Part of the goal of using ZFS is to simplify and harden backups. I wanted to experiment with shorter recovery times specifically both point in time recovery objective and recovery time objective and faster incremental backups. This is, therefore, part of my backup services. This section documents how an external NVMe enclosure was setup in a pool to mirror the datasets from my workstation. The final setup should include syncoid copying datasets to the backup server regularly, but I haven't finished that configuration yet.

Partitioning The above partitioning procedure used sgdisk, but I couldn't figure out how to do this with sgdisk, so this uses sfdisk to dump the partition from the first disk to an external, identical drive:
sfdisk -d /dev/nvme0n1   sfdisk --no-reread /dev/sda --force

Pool creation This is similar to the main pool creation, except we tweaked a few bits after changing the upstream procedure:
zpool create \
        -o cachefile=/etc/zfs/zpool.cache \
        -o ashift=12 -d \
        -o feature@async_destroy=enabled \
        -o feature@bookmarks=enabled \
        -o feature@embedded_data=enabled \
        -o feature@empty_bpobj=enabled \
        -o feature@enabled_txg=enabled \
        -o feature@extensible_dataset=enabled \
        -o feature@filesystem_limits=enabled \
        -o feature@hole_birth=enabled \
        -o feature@large_blocks=enabled \
        -o feature@lz4_compress=enabled \
        -o feature@spacemap_histogram=enabled \
        -o feature@zpool_checkpoint=enabled \
        -O acltype=posixacl -O xattr=sa \
        -O compression=lz4 \
        -O devices=off \
        -O relatime=on \
        -O canmount=off \
        -O mountpoint=/boot -R /mnt \
        bpool-tubman /dev/sdb3
The change from the main boot pool are: Main pool creation is:
zpool create \
        -o ashift=12 \
        -O encryption=on -O keylocation=prompt -O keyformat=passphrase \
        -O acltype=posixacl -O xattr=sa -O dnodesize=auto \
        -O compression=zstd \
        -O relatime=on \
        -O canmount=off \
        -O mountpoint=/ -R /mnt \
        rpool-tubman /dev/sdb4

First sync I used syncoid to copy all pools over to the external device. syncoid is a thing that's part of the sanoid project which is specifically designed to sync snapshots between pool, typically over SSH links but it can also operate locally. The sanoid command had a --readonly argument to simulate changes, but syncoid didn't so I tried to fix that with an upstream PR. It seems it would be better to do this by hand, but this was much easier. The full first sync was:
root@curie:/home/anarcat# ./bin/syncoid -r  bpool bpool-tubman
CRITICAL ERROR: Target bpool-tubman exists but has no snapshots matching with bpool!
                Replication to target would require destroying existing
                target. Cowardly refusing to destroy your existing target.
          NOTE: Target bpool-tubman dataset is < 64MB used - did you mistakenly run
                 zfs create bpool-tubman  on the target? ZFS initial
                replication must be to a NON EXISTENT DATASET, which will
                then be CREATED BY the initial replication process.
INFO: Sending oldest full snapshot bpool/BOOT@test (~ 42 KB) to new target filesystem:
44.2KiB 0:00:00 [4.19MiB/s] [========================================================================================================================] 103%            
INFO: Updating new target filesystem with incremental bpool/BOOT@test ... syncoid_curie_2022-05-30:12:50:39 (~ 4 KB):
2.13KiB 0:00:00 [ 114KiB/s] [===============================================================>                                                         ] 53%            
INFO: Sending oldest full snapshot bpool/BOOT/debian@install (~ 126.0 MB) to new target filesystem:
 126MiB 0:00:00 [ 308MiB/s] [=======================================================================================================================>] 100%            
INFO: Updating new target filesystem with incremental bpool/BOOT/debian@install ... syncoid_curie_2022-05-30:12:50:39 (~ 113.4 MB):
 113MiB 0:00:00 [ 315MiB/s] [=======================================================================================================================>] 100%
root@curie:/home/anarcat# ./bin/syncoid -r  rpool rpool-tubman
CRITICAL ERROR: Target rpool-tubman exists but has no snapshots matching with rpool!
                Replication to target would require destroying existing
                target. Cowardly refusing to destroy your existing target.
          NOTE: Target rpool-tubman dataset is < 64MB used - did you mistakenly run
                 zfs create rpool-tubman  on the target? ZFS initial
                replication must be to a NON EXISTENT DATASET, which will
                then be CREATED BY the initial replication process.
INFO: Sending oldest full snapshot rpool/ROOT@syncoid_curie_2022-05-30:12:50:51 (~ 69 KB) to new target filesystem:
44.2KiB 0:00:00 [2.44MiB/s] [===========================================================================>                                             ] 63%            
INFO: Sending oldest full snapshot rpool/ROOT/debian@install (~ 25.9 GB) to new target filesystem:
25.9GiB 0:03:33 [ 124MiB/s] [=======================================================================================================================>] 100%            
INFO: Updating new target filesystem with incremental rpool/ROOT/debian@install ... syncoid_curie_2022-05-30:12:50:52 (~ 3.9 GB):
3.92GiB 0:00:33 [ 119MiB/s] [======================================================================================================================>  ] 99%            
INFO: Sending oldest full snapshot rpool/home@syncoid_curie_2022-05-30:12:55:04 (~ 276.8 GB) to new target filesystem:
 277GiB 0:27:13 [ 174MiB/s] [=======================================================================================================================>] 100%            
INFO: Sending oldest full snapshot rpool/home/root@syncoid_curie_2022-05-30:13:22:19 (~ 2.2 GB) to new target filesystem:
2.22GiB 0:00:25 [90.2MiB/s] [=======================================================================================================================>] 100%            
INFO: Sending oldest full snapshot rpool/var@syncoid_curie_2022-05-30:13:22:47 (~ 5.6 GB) to new target filesystem:
5.56GiB 0:00:32 [ 176MiB/s] [=======================================================================================================================>] 100%            
INFO: Sending oldest full snapshot rpool/var/cache@syncoid_curie_2022-05-30:13:23:22 (~ 627.3 MB) to new target filesystem:
 627MiB 0:00:03 [ 169MiB/s] [=======================================================================================================================>] 100%            
INFO: Sending oldest full snapshot rpool/var/lib@syncoid_curie_2022-05-30:13:23:28 (~ 69 KB) to new target filesystem:
44.2KiB 0:00:00 [1.40MiB/s] [===========================================================================>                                             ] 63%            
INFO: Sending oldest full snapshot rpool/var/lib/docker@syncoid_curie_2022-05-30:13:23:28 (~ 442.6 MB) to new target filesystem:
 443MiB 0:00:04 [ 103MiB/s] [=======================================================================================================================>] 100%            
INFO: Sending oldest full snapshot rpool/var/lib/docker/05c0de7fabbea60500eaa495d0d82038249f6faa63b12914737c4d71520e62c5@266253254 (~ 6.3 MB) to new target filesystem:
6.49MiB 0:00:00 [12.9MiB/s] [========================================================================================================================] 102%            
INFO: Updating new target filesystem with incremental rpool/var/lib/docker/05c0de7fabbea60500eaa495d0d82038249f6faa63b12914737c4d71520e62c5@266253254 ... syncoid_curie_2022-05-30:13:23:34 (~ 4 KB):
1.52KiB 0:00:00 [27.6KiB/s] [============================================>                                                                            ] 38%            
INFO: Sending oldest full snapshot rpool/var/lib/flatpak@syncoid_curie_2022-05-30:13:23:36 (~ 2.0 GB) to new target filesystem:
2.00GiB 0:00:17 [ 115MiB/s] [=======================================================================================================================>] 100%            
INFO: Sending oldest full snapshot rpool/var/tmp@syncoid_curie_2022-05-30:13:23:55 (~ 57.0 MB) to new target filesystem:
61.8MiB 0:00:01 [45.0MiB/s] [========================================================================================================================] 108%            
INFO: Clone is recreated on target rpool-tubman/var/lib/docker/ed71ddd563a779ba6fb37b3b1d0cc2c11eca9b594e77b4b234867ebcb162b205 based on rpool/var/lib/docker/05c0de7fabbea60500eaa495d0d82038249f6faa63b12914737c4d71520e62c5@266253254
INFO: Sending oldest full snapshot rpool/var/lib/docker/ed71ddd563a779ba6fb37b3b1d0cc2c11eca9b594e77b4b234867ebcb162b205@syncoid_curie_2022-05-30:13:23:58 (~ 218.6 MB) to new target filesystem:
 219MiB 0:00:01 [ 151MiB/s] [=======================================================================================================================>] 100%
Funny how the CRITICAL ERROR doesn't actually stop syncoid and it just carries on merrily doing when it's telling you it's "cowardly refusing to destroy your existing target"... Maybe that's because my pull request broke something though... During the transfer, the computer was very sluggish: everything feels like it has ~30-50ms latency extra:
anarcat@curie:sanoid$ LANG=C top -b  -n 1   head -20
top - 13:07:05 up 6 days,  4:01,  1 user,  load average: 16.13, 16.55, 11.83
Tasks: 606 total,   6 running, 598 sleeping,   0 stopped,   2 zombie
%Cpu(s): 18.8 us, 72.5 sy,  1.2 ni,  5.0 id,  1.2 wa,  0.0 hi,  1.2 si,  0.0 st
MiB Mem :  15898.4 total,   1387.6 free,  13170.0 used,   1340.8 buff/cache
MiB Swap:      0.0 total,      0.0 free,      0.0 used.   1319.8 avail Mem 
    PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND
     70 root      20   0       0      0      0 S  83.3   0.0   6:12.67 kswapd0
4024878 root      20   0  282644  96432  10288 S  44.4   0.6   0:11.43 puppet
3896136 root      20   0   35328  16528     48 S  22.2   0.1   2:08.04 mbuffer
3896135 root      20   0   10328    776    168 R  16.7   0.0   1:22.93 zfs
3896138 root      20   0   10588    788    156 R  16.7   0.0   1:49.30 zfs
    350 root       0 -20       0      0      0 R  11.1   0.0   1:03.53 z_rd_int
    351 root       0 -20       0      0      0 S  11.1   0.0   1:04.15 z_rd_int
3896137 root      20   0    4384    352    244 R  11.1   0.0   0:44.73 pv
4034094 anarcat   30  10   20028  13960   2428 S  11.1   0.1   0:00.70 mbsync
4036539 anarcat   20   0    9604   3464   2408 R  11.1   0.0   0:00.04 top
    352 root       0 -20       0      0      0 S   5.6   0.0   1:03.64 z_rd_int
    353 root       0 -20       0      0      0 S   5.6   0.0   1:03.64 z_rd_int
    354 root       0 -20       0      0      0 S   5.6   0.0   1:04.01 z_rd_int
I wonder how much of that is due to syncoid, particularly because I often saw mbuffer and pv in there which are not strictly necessary to do those kind of operations, as far as I understand. Once that's done, export the pools to disconnect the drive:
zpool export bpool-tubman
zpool export rpool-tubman

Raw disk benchmark Copied the 512GB SSD/M.2 device to another 1024GB NVMe/M.2 device:
anarcat@curie:~$ sudo dd if=/dev/sdb of=/dev/sdc bs=4M status=progress conv=fdatasync
499944259584 octets (500 GB, 466 GiB) copi s, 1713 s, 292 MB/s
119235+1 enregistrements lus
119235+1 enregistrements  crits
500107862016 octets (500 GB, 466 GiB) copi s, 1719,93 s, 291 MB/s
... while both over USB, whoohoo 300MB/s!

Monitoring ZFS should be monitoring your pools regularly. Normally, the [[!debman zed]] daemon monitors all ZFS events. It is the thing that will report when a scrub failed, for example. See this configuration guide. Scrubs should be regularly scheduled to ensure consistency of the pool. This can be done in newer zfsutils-linux versions (bullseye-backports or bookworm) with one of those, depending on the desired frequency:
systemctl enable zfs-scrub-weekly@rpool.timer --now
systemctl enable zfs-scrub-monthly@rpool.timer --now
When the scrub runs, if it finds anything it will send an event which will get picked up by the zed daemon which will then send a notification, see below for an example. TODO: deploy on curie, if possible (probably not because no RAID) TODO: this should be in Puppet

Scrub warning example So what happens when problems are found? Here's an example of how I dealt with an error I received. After setting up another server (tubman) with ZFS, I eventually ended up getting a warning from the ZFS toolchain.
Date: Sun, 09 Oct 2022 00:58:08 -0400
From: root <root@anarc.at>
To: root@anarc.at
Subject: ZFS scrub_finish event for rpool on tubman
ZFS has finished a scrub:
   eid: 39536
 class: scrub_finish
  host: tubman
  time: 2022-10-09 00:58:07-0400
  pool: rpool
 state: ONLINE
status: One or more devices has experienced an unrecoverable error.  An
        attempt was made to correct the error.  Applications are unaffected.
action: Determine if the device needs to be replaced, and clear the errors
        using 'zpool clear' or replace the device with 'zpool replace'.
   see: https://openzfs.github.io/openzfs-docs/msg/ZFS-8000-9P
  scan: scrub repaired 0B in 00:33:57 with 0 errors on Sun Oct  9 00:58:07 2022
config:
        NAME        STATE     READ WRITE CKSUM
        rpool       ONLINE       0     0     0
          mirror-0  ONLINE       0     0     0
            sdb4    ONLINE       0     1     0
            sdc4    ONLINE       0     0     0
        cache
          sda3      ONLINE       0     0     0
errors: No known data errors
This, in itself, is a little worrisome. But it helpfully links to this more detailed documentation (and props up there: the link still works) which explains this is a "minor" problem (something that could be included in the report). In this case, this happened on a server setup on 2021-04-28, but the disks and server hardware are much older. The server itself (marcos v1) was built around 2011, over 10 years ago now. The hard drive in question is:
root@tubman:~# smartctl -i -qnoserial /dev/sdb
smartctl 7.2 2020-12-30 r5155 [x86_64-linux-5.10.0-15-amd64] (local build)
Copyright (C) 2002-20, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF INFORMATION SECTION ===
Model Family:     Seagate BarraCuda 3.5
Device Model:     ST4000DM004-2CV104
Firmware Version: 0001
User Capacity:    4,000,787,030,016 bytes [4.00 TB]
Sector Sizes:     512 bytes logical, 4096 bytes physical
Rotation Rate:    5425 rpm
Form Factor:      3.5 inches
Device is:        In smartctl database [for details use: -P show]
ATA Version is:   ACS-3 T13/2161-D revision 5
SATA Version is:  SATA 3.1, 6.0 Gb/s (current: 3.0 Gb/s)
Local Time is:    Tue Oct 11 11:02:32 2022 EDT
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
Some more SMART stats:
root@tubman:~# smartctl -a -qnoserial /dev/sdb   grep -e  Head_Flying_Hours -e Power_On_Hours -e Total_LBA -e 'Sector Sizes'
Sector Sizes:     512 bytes logical, 4096 bytes physical
  9 Power_On_Hours          0x0032   086   086   000    Old_age   Always       -       12464 (206 202 0)
240 Head_Flying_Hours       0x0000   100   253   000    Old_age   Offline      -       10966h+55m+23.757s
241 Total_LBAs_Written      0x0000   100   253   000    Old_age   Offline      -       21107792664
242 Total_LBAs_Read         0x0000   100   253   000    Old_age   Offline      -       3201579750
That's over a year of power on, which shouldn't be so bad. It has written about 10TB of data (21107792664 LBAs * 512 byte/LBA), which is about two full writes. According to its specification, this device is supposed to support 55 TB/year of writes, so we're far below spec. Note that are still far from the "non-recoverable read error per bits" spec (1 per 10E15), as we've basically read 13E12 bits (3201579750 LBAs * 512 byte/LBA = 13E12 bits). It's likely this disk was made in 2018, so it is in its fourth year. Interestingly, /dev/sdc is also a Seagate drive, but of a different series:
root@tubman:~# smartctl -qnoserial  -i /dev/sdb
smartctl 7.2 2020-12-30 r5155 [x86_64-linux-5.10.0-15-amd64] (local build)
Copyright (C) 2002-20, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF INFORMATION SECTION ===
Model Family:     Seagate BarraCuda 3.5
Device Model:     ST4000DM004-2CV104
Firmware Version: 0001
User Capacity:    4,000,787,030,016 bytes [4.00 TB]
Sector Sizes:     512 bytes logical, 4096 bytes physical
Rotation Rate:    5425 rpm
Form Factor:      3.5 inches
Device is:        In smartctl database [for details use: -P show]
ATA Version is:   ACS-3 T13/2161-D revision 5
SATA Version is:  SATA 3.1, 6.0 Gb/s (current: 3.0 Gb/s)
Local Time is:    Tue Oct 11 11:21:35 2022 EDT
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
It has seen much more reads than the other disk which is also interesting:
root@tubman:~# smartctl -a -qnoserial /dev/sdc   grep -e  Head_Flying_Hours -e Power_On_Hours -e Total_LBA -e 'Sector Sizes'
Sector Sizes:     512 bytes logical, 4096 bytes physical
  9 Power_On_Hours          0x0032   059   059   000    Old_age   Always       -       36240
240 Head_Flying_Hours       0x0000   100   253   000    Old_age   Offline      -       33994h+10m+52.118s
241 Total_LBAs_Written      0x0000   100   253   000    Old_age   Offline      -       30730174438
242 Total_LBAs_Read         0x0000   100   253   000    Old_age   Offline      -       51894566538
That's 4 years of Head_Flying_Hours, and over 4 years (4 years and 48 days) of Power_On_Hours. The copyright date on that drive's specs goes back to 2016, so it's a much older drive. SMART self-test succeeded.

Remaining issues
  • TODO: move send/receive backups to offsite host, see also zfs for alternatives to syncoid/sanoid there
  • TODO: setup backup cron job (or timer?)
  • TODO: swap still not setup on curie, see zfs
  • TODO: document this somewhere: bpool and rpool are both pools and datasets. that's pretty confusing, but also very useful because it allows for pool-wide recursive snapshots, which are used for the backup system

fio improvements I really want to improve my experience with fio. Right now, I'm just cargo-culting stuff from other folks and I don't really like it. stressant is a good example of my struggles, in the sense that it doesn't really work that well for disk tests. I would love to have just a single .fio job file that lists multiple jobs to run serially. For example, this file describes the above workload pretty well:
[global]
# cargo-culting Salter
fallocate=none
ioengine=posixaio
runtime=60
time_based=1
end_fsync=1
stonewall=1
group_reporting=1
# no need to drop caches, done by default
# invalidate=1
# Single 4KiB random read/write process
[randread-4k-4g-1x]
rw=randread
bs=4k
size=4g
numjobs=1
iodepth=1
[randwrite-4k-4g-1x]
rw=randwrite
bs=4k
size=4g
numjobs=1
iodepth=1
# 16 parallel 64KiB random read/write processes:
[randread-64k-256m-16x]
rw=randread
bs=64k
size=256m
numjobs=16
iodepth=16
[randwrite-64k-256m-16x]
rw=randwrite
bs=64k
size=256m
numjobs=16
iodepth=16
# Single 1MiB random read/write process
[randread-1m-16g-1x]
rw=randread
bs=1m
size=16g
numjobs=1
iodepth=1
[randwrite-1m-16g-1x]
rw=randwrite
bs=1m
size=16g
numjobs=1
iodepth=1
... except the jobs are actually started in parallel, even though they are stonewall'd, as far as I can tell by the reports. I sent a mail to the fio mailing list for clarification. It looks like the jobs are started in parallel, but actual (correctly) run serially. It seems like this might just be a matter of reporting the right timestamps in the end, although it does feel like starting all the processes (even if not doing any work yet) could skew the results.

Hangs during procedure During the procedure, it happened a few times where any ZFS command would completely hang. It seems that using an external USB drive to sync stuff didn't work so well: sometimes it would reconnect under a different device (from sdc to sdd, for example), and this would greatly confuse ZFS. Here, for example, is sdd reappearing out of the blue:
May 19 11:22:53 curie kernel: [  699.820301] scsi host4: uas
May 19 11:22:53 curie kernel: [  699.820544] usb 2-1: authorized to connect
May 19 11:22:53 curie kernel: [  699.922433] scsi 4:0:0:0: Direct-Access     ROG      ESD-S1C          0    PQ: 0 ANSI: 6
May 19 11:22:53 curie kernel: [  699.923235] sd 4:0:0:0: Attached scsi generic sg2 type 0
May 19 11:22:53 curie kernel: [  699.923676] sd 4:0:0:0: [sdd] 1953525168 512-byte logical blocks: (1.00 TB/932 GiB)
May 19 11:22:53 curie kernel: [  699.923788] sd 4:0:0:0: [sdd] Write Protect is off
May 19 11:22:53 curie kernel: [  699.923949] sd 4:0:0:0: [sdd] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
May 19 11:22:53 curie kernel: [  699.924149] sd 4:0:0:0: [sdd] Optimal transfer size 33553920 bytes
May 19 11:22:53 curie kernel: [  699.961602]  sdd: sdd1 sdd2 sdd3 sdd4
May 19 11:22:53 curie kernel: [  699.996083] sd 4:0:0:0: [sdd] Attached SCSI disk
Next time I run a ZFS command (say zpool list), the command completely hangs (D state) and this comes up in the logs:
May 19 11:34:21 curie kernel: [ 1387.914843] zio pool=bpool vdev=/dev/sdc3 error=5 type=2 offset=71344128 size=4096 flags=184880
May 19 11:34:21 curie kernel: [ 1387.914859] zio pool=bpool vdev=/dev/sdc3 error=5 type=2 offset=205565952 size=4096 flags=184880
May 19 11:34:21 curie kernel: [ 1387.914874] zio pool=bpool vdev=/dev/sdc3 error=5 type=2 offset=272789504 size=4096 flags=184880
May 19 11:34:21 curie kernel: [ 1387.914906] zio pool=bpool vdev=/dev/sdc3 error=5 type=1 offset=270336 size=8192 flags=b08c1
May 19 11:34:21 curie kernel: [ 1387.914932] zio pool=bpool vdev=/dev/sdc3 error=5 type=1 offset=1073225728 size=8192 flags=b08c1
May 19 11:34:21 curie kernel: [ 1387.914948] zio pool=bpool vdev=/dev/sdc3 error=5 type=1 offset=1073487872 size=8192 flags=b08c1
May 19 11:34:21 curie kernel: [ 1387.915165] zio pool=bpool vdev=/dev/sdc3 error=5 type=2 offset=272793600 size=4096 flags=184880
May 19 11:34:21 curie kernel: [ 1387.915183] zio pool=bpool vdev=/dev/sdc3 error=5 type=2 offset=339853312 size=4096 flags=184880
May 19 11:34:21 curie kernel: [ 1387.915648] WARNING: Pool 'bpool' has encountered an uncorrectable I/O failure and has been suspended.
May 19 11:34:21 curie kernel: [ 1387.915648] 
May 19 11:37:25 curie kernel: [ 1571.558614] task:txg_sync        state:D stack:    0 pid:  997 ppid:     2 flags:0x00004000
May 19 11:37:25 curie kernel: [ 1571.558623] Call Trace:
May 19 11:37:25 curie kernel: [ 1571.558640]  __schedule+0x282/0x870
May 19 11:37:25 curie kernel: [ 1571.558650]  schedule+0x46/0xb0
May 19 11:37:25 curie kernel: [ 1571.558670]  schedule_timeout+0x8b/0x140
May 19 11:37:25 curie kernel: [ 1571.558675]  ? __next_timer_interrupt+0x110/0x110
May 19 11:37:25 curie kernel: [ 1571.558678]  io_schedule_timeout+0x4c/0x80
May 19 11:37:25 curie kernel: [ 1571.558689]  __cv_timedwait_common+0x12b/0x160 [spl]
May 19 11:37:25 curie kernel: [ 1571.558694]  ? add_wait_queue_exclusive+0x70/0x70
May 19 11:37:25 curie kernel: [ 1571.558702]  __cv_timedwait_io+0x15/0x20 [spl]
May 19 11:37:25 curie kernel: [ 1571.558816]  zio_wait+0x129/0x2b0 [zfs]
May 19 11:37:25 curie kernel: [ 1571.558929]  dsl_pool_sync+0x461/0x4f0 [zfs]
May 19 11:37:25 curie kernel: [ 1571.559032]  spa_sync+0x575/0xfa0 [zfs]
May 19 11:37:25 curie kernel: [ 1571.559138]  ? spa_txg_history_init_io+0x101/0x110 [zfs]
May 19 11:37:25 curie kernel: [ 1571.559245]  txg_sync_thread+0x2e0/0x4a0 [zfs]
May 19 11:37:25 curie kernel: [ 1571.559354]  ? txg_fini+0x240/0x240 [zfs]
May 19 11:37:25 curie kernel: [ 1571.559366]  thread_generic_wrapper+0x6f/0x80 [spl]
May 19 11:37:25 curie kernel: [ 1571.559376]  ? __thread_exit+0x20/0x20 [spl]
May 19 11:37:25 curie kernel: [ 1571.559379]  kthread+0x11b/0x140
May 19 11:37:25 curie kernel: [ 1571.559382]  ? __kthread_bind_mask+0x60/0x60
May 19 11:37:25 curie kernel: [ 1571.559386]  ret_from_fork+0x22/0x30
May 19 11:37:25 curie kernel: [ 1571.559401] task:zed             state:D stack:    0 pid: 1564 ppid:     1 flags:0x00000000
May 19 11:37:25 curie kernel: [ 1571.559404] Call Trace:
May 19 11:37:25 curie kernel: [ 1571.559409]  __schedule+0x282/0x870
May 19 11:37:25 curie kernel: [ 1571.559412]  ? __kmalloc_node+0x141/0x2b0
May 19 11:37:25 curie kernel: [ 1571.559417]  schedule+0x46/0xb0
May 19 11:37:25 curie kernel: [ 1571.559420]  schedule_preempt_disabled+0xa/0x10
May 19 11:37:25 curie kernel: [ 1571.559424]  __mutex_lock.constprop.0+0x133/0x460
May 19 11:37:25 curie kernel: [ 1571.559435]  ? nvlist_xalloc.part.0+0x68/0xc0 [znvpair]
May 19 11:37:25 curie kernel: [ 1571.559537]  spa_all_configs+0x41/0x120 [zfs]
May 19 11:37:25 curie kernel: [ 1571.559644]  zfs_ioc_pool_configs+0x17/0x70 [zfs]
May 19 11:37:25 curie kernel: [ 1571.559752]  zfsdev_ioctl_common+0x697/0x870 [zfs]
May 19 11:37:25 curie kernel: [ 1571.559758]  ? _copy_from_user+0x28/0x60
May 19 11:37:25 curie kernel: [ 1571.559860]  zfsdev_ioctl+0x53/0xe0 [zfs]
May 19 11:37:25 curie kernel: [ 1571.559866]  __x64_sys_ioctl+0x83/0xb0
May 19 11:37:25 curie kernel: [ 1571.559869]  do_syscall_64+0x33/0x80
May 19 11:37:25 curie kernel: [ 1571.559873]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
May 19 11:37:25 curie kernel: [ 1571.559876] RIP: 0033:0x7fcf0ef32cc7
May 19 11:37:25 curie kernel: [ 1571.559878] RSP: 002b:00007fcf0e181618 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
May 19 11:37:25 curie kernel: [ 1571.559881] RAX: ffffffffffffffda RBX: 000055b212f972a0 RCX: 00007fcf0ef32cc7
May 19 11:37:25 curie kernel: [ 1571.559883] RDX: 00007fcf0e181640 RSI: 0000000000005a04 RDI: 000000000000000b
May 19 11:37:25 curie kernel: [ 1571.559885] RBP: 00007fcf0e184c30 R08: 00007fcf08016810 R09: 00007fcf08000080
May 19 11:37:25 curie kernel: [ 1571.559886] R10: 0000000000080000 R11: 0000000000000246 R12: 000055b212f972a0
May 19 11:37:25 curie kernel: [ 1571.559888] R13: 0000000000000000 R14: 00007fcf0e181640 R15: 0000000000000000
May 19 11:37:25 curie kernel: [ 1571.559980] task:zpool           state:D stack:    0 pid:11815 ppid:  3816 flags:0x00004000
May 19 11:37:25 curie kernel: [ 1571.559983] Call Trace:
May 19 11:37:25 curie kernel: [ 1571.559988]  __schedule+0x282/0x870
May 19 11:37:25 curie kernel: [ 1571.559992]  schedule+0x46/0xb0
May 19 11:37:25 curie kernel: [ 1571.559995]  io_schedule+0x42/0x70
May 19 11:37:25 curie kernel: [ 1571.560004]  cv_wait_common+0xac/0x130 [spl]
May 19 11:37:25 curie kernel: [ 1571.560008]  ? add_wait_queue_exclusive+0x70/0x70
May 19 11:37:25 curie kernel: [ 1571.560118]  txg_wait_synced_impl+0xc9/0x110 [zfs]
May 19 11:37:25 curie kernel: [ 1571.560223]  txg_wait_synced+0xc/0x40 [zfs]
May 19 11:37:25 curie kernel: [ 1571.560325]  spa_export_common+0x4cd/0x590 [zfs]
May 19 11:37:25 curie kernel: [ 1571.560430]  ? zfs_log_history+0x9c/0xf0 [zfs]
May 19 11:37:25 curie kernel: [ 1571.560537]  zfsdev_ioctl_common+0x697/0x870 [zfs]
May 19 11:37:25 curie kernel: [ 1571.560543]  ? _copy_from_user+0x28/0x60
May 19 11:37:25 curie kernel: [ 1571.560644]  zfsdev_ioctl+0x53/0xe0 [zfs]
May 19 11:37:25 curie kernel: [ 1571.560649]  __x64_sys_ioctl+0x83/0xb0
May 19 11:37:25 curie kernel: [ 1571.560653]  do_syscall_64+0x33/0x80
May 19 11:37:25 curie kernel: [ 1571.560656]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
May 19 11:37:25 curie kernel: [ 1571.560659] RIP: 0033:0x7fdc23be2cc7
May 19 11:37:25 curie kernel: [ 1571.560661] RSP: 002b:00007ffc8c792478 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
May 19 11:37:25 curie kernel: [ 1571.560664] RAX: ffffffffffffffda RBX: 000055942ca49e20 RCX: 00007fdc23be2cc7
May 19 11:37:25 curie kernel: [ 1571.560666] RDX: 00007ffc8c792490 RSI: 0000000000005a03 RDI: 0000000000000003
May 19 11:37:25 curie kernel: [ 1571.560667] RBP: 00007ffc8c795e80 R08: 00000000ffffffff R09: 00007ffc8c792310
May 19 11:37:25 curie kernel: [ 1571.560669] R10: 000055942ca49e30 R11: 0000000000000246 R12: 00007ffc8c792490
May 19 11:37:25 curie kernel: [ 1571.560671] R13: 000055942ca49e30 R14: 000055942aed2c20 R15: 00007ffc8c795a40
Here's another example, where you see the USB controller bleeping out and back into existence:
mai 19 11:38:39 curie kernel: usb 2-1: USB disconnect, device number 2
mai 19 11:38:39 curie kernel: sd 4:0:0:0: [sdd] Synchronizing SCSI cache
mai 19 11:38:39 curie kernel: sd 4:0:0:0: [sdd] Synchronize Cache(10) failed: Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK
mai 19 11:39:25 curie kernel: INFO: task zed:1564 blocked for more than 241 seconds.
mai 19 11:39:25 curie kernel:       Tainted: P          IOE     5.10.0-14-amd64 #1 Debian 5.10.113-1
mai 19 11:39:25 curie kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
mai 19 11:39:25 curie kernel: task:zed             state:D stack:    0 pid: 1564 ppid:     1 flags:0x00000000
mai 19 11:39:25 curie kernel: Call Trace:
mai 19 11:39:25 curie kernel:  __schedule+0x282/0x870
mai 19 11:39:25 curie kernel:  ? __kmalloc_node+0x141/0x2b0
mai 19 11:39:25 curie kernel:  schedule+0x46/0xb0
mai 19 11:39:25 curie kernel:  schedule_preempt_disabled+0xa/0x10
mai 19 11:39:25 curie kernel:  __mutex_lock.constprop.0+0x133/0x460
mai 19 11:39:25 curie kernel:  ? nvlist_xalloc.part.0+0x68/0xc0 [znvpair]
mai 19 11:39:25 curie kernel:  spa_all_configs+0x41/0x120 [zfs]
mai 19 11:39:25 curie kernel:  zfs_ioc_pool_configs+0x17/0x70 [zfs]
mai 19 11:39:25 curie kernel:  zfsdev_ioctl_common+0x697/0x870 [zfs]
mai 19 11:39:25 curie kernel:  ? _copy_from_user+0x28/0x60
mai 19 11:39:25 curie kernel:  zfsdev_ioctl+0x53/0xe0 [zfs]
mai 19 11:39:25 curie kernel:  __x64_sys_ioctl+0x83/0xb0
mai 19 11:39:25 curie kernel:  do_syscall_64+0x33/0x80
mai 19 11:39:25 curie kernel:  entry_SYSCALL_64_after_hwframe+0x44/0xa9
mai 19 11:39:25 curie kernel: RIP: 0033:0x7fcf0ef32cc7
mai 19 11:39:25 curie kernel: RSP: 002b:00007fcf0e181618 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
mai 19 11:39:25 curie kernel: RAX: ffffffffffffffda RBX: 000055b212f972a0 RCX: 00007fcf0ef32cc7
mai 19 11:39:25 curie kernel: RDX: 00007fcf0e181640 RSI: 0000000000005a04 RDI: 000000000000000b
mai 19 11:39:25 curie kernel: RBP: 00007fcf0e184c30 R08: 00007fcf08016810 R09: 00007fcf08000080
mai 19 11:39:25 curie kernel: R10: 0000000000080000 R11: 0000000000000246 R12: 000055b212f972a0
mai 19 11:39:25 curie kernel: R13: 0000000000000000 R14: 00007fcf0e181640 R15: 0000000000000000
mai 19 11:39:25 curie kernel: INFO: task zpool:11815 blocked for more than 241 seconds.
mai 19 11:39:25 curie kernel:       Tainted: P          IOE     5.10.0-14-amd64 #1 Debian 5.10.113-1
mai 19 11:39:25 curie kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
mai 19 11:39:25 curie kernel: task:zpool           state:D stack:    0 pid:11815 ppid:  2621 flags:0x00004004
mai 19 11:39:25 curie kernel: Call Trace:
mai 19 11:39:25 curie kernel:  __schedule+0x282/0x870
mai 19 11:39:25 curie kernel:  schedule+0x46/0xb0
mai 19 11:39:25 curie kernel:  io_schedule+0x42/0x70
mai 19 11:39:25 curie kernel:  cv_wait_common+0xac/0x130 [spl]
mai 19 11:39:25 curie kernel:  ? add_wait_queue_exclusive+0x70/0x70
mai 19 11:39:25 curie kernel:  txg_wait_synced_impl+0xc9/0x110 [zfs]
mai 19 11:39:25 curie kernel:  txg_wait_synced+0xc/0x40 [zfs]
mai 19 11:39:25 curie kernel:  spa_export_common+0x4cd/0x590 [zfs]
mai 19 11:39:25 curie kernel:  ? zfs_log_history+0x9c/0xf0 [zfs]
mai 19 11:39:25 curie kernel:  zfsdev_ioctl_common+0x697/0x870 [zfs]
mai 19 11:39:25 curie kernel:  ? _copy_from_user+0x28/0x60
mai 19 11:39:25 curie kernel:  zfsdev_ioctl+0x53/0xe0 [zfs]
mai 19 11:39:25 curie kernel:  __x64_sys_ioctl+0x83/0xb0
mai 19 11:39:25 curie kernel:  do_syscall_64+0x33/0x80
mai 19 11:39:25 curie kernel:  entry_SYSCALL_64_after_hwframe+0x44/0xa9
mai 19 11:39:25 curie kernel: RIP: 0033:0x7fdc23be2cc7
mai 19 11:39:25 curie kernel: RSP: 002b:00007ffc8c792478 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
mai 19 11:39:25 curie kernel: RAX: ffffffffffffffda RBX: 000055942ca49e20 RCX: 00007fdc23be2cc7
mai 19 11:39:25 curie kernel: RDX: 00007ffc8c792490 RSI: 0000000000005a03 RDI: 0000000000000003
mai 19 11:39:25 curie kernel: RBP: 00007ffc8c795e80 R08: 00000000ffffffff R09: 00007ffc8c792310
mai 19 11:39:25 curie kernel: R10: 000055942ca49e30 R11: 0000000000000246 R12: 00007ffc8c792490
mai 19 11:39:25 curie kernel: R13: 000055942ca49e30 R14: 000055942aed2c20 R15: 00007ffc8c795a40
I understand those are rather extreme conditions: I would fully expect the pool to stop working if the underlying drives disappear. What doesn't seem acceptable is that a command would completely hang like this.

References See the zfs documentation for more information about ZFS, and tubman for another installation and migration procedure.

1 November 2022

Paul Tagliamonte: Decoding LDPC: k-Bit Brute Forcing

Before you go on: I've been warned off implementing this in practice on a few counts; namely, the space tradeoff isn't worth it, and it's unlikely to correct meaningful errors. I'm going to leave this post up, but please do take the content with a very large grain of salt!
My initial efforts to build a PHY and Data Link layer from scratch using my own code have been progressing nicely since the initial BPSK based protocol I ve documented under the PACKRAT series. As part of that, I ve been diving deep into FEC, and in particular, LDPC. I won t be able to do an overview of LDPC justice in this post with any luck that ll come in a later post to come as part of the RATPACK series, so some knowledge is assumed. As such this post is less useful for those looking to learn about LDPC, and a bit more targeted to those who enjoy talking and thinking about FEC.
Hey, heads up! - This post contains extremely unvalidated and back of the napkin quality work without any effort to prove this out generally. Hopefully this work can be of help to others, but please double check anything below if you need it for your own work!
While implementing LDPC, I ve gotten an encoder and checker working, enough to use LDPC like a checksum. The next big step is to write a Decoder, which can do error correction. The two popular approaches for the actual correction that I ve seen while reading about LDPC are Belief Propagation, and some class of linear programming that I haven t dug into yet. I m not thrilled at how expensive this all is in software, so while implementing the stack I ve been exploring every shady side ally to try and learn more about how encoders and decoders work, both in theory - and in practice.

Processing an LDPC Message Checking if a message is correct is fairly straightforward with LDPC (as with encoding, I ll note). As a quick refresher given the LDPC H (check) matrix of width N, you can check your message vector (msg) of length N by multipling H and msg, and checking if the output vector is all zero.
 // scheme contains our G (generator) and
 // H (check) matrices.
 scheme :=  G: Matrix ... , H: Matrix ... 
// msg contains our LDPC message (data and
 // check bits).
 msg := Vector ... 
// N is also the length of the encoded
 // msg vector after check bits have been
 // added.
 N := scheme.G.Width
// Now, let's generate our 'check' vector.
 ch := Multiply(scheme.H, msg)
We can now see if the message is correct or not:
 // if the ch vector is all zeros, we know
 // that the message is valid, and we don't
 // need to do anything.
 if ch.IsZero()  
// handle the case where the message
 // is fine as-is.
 return ...
 
// Expensive decode here
This is great for getting a thumbs up / thumbs down on the message being correct, but correcting errors still requires pulling the LDPC matrix values from the g (generator) matrix out, building a bipartite graph, and iteratively reprocessing the bit values, until constraints are satisfied and the message has been corrected. This got me thinking - what is the output vector when it s not all zeros? Since 1 values in the output vector indicates consistency problems in the message bits as they relate to the check bits, I wondered if this could be used to speed up my LDPC decoder. It appears to work, so this post is half an attempt to document this technique before I put it in my hot path, and half a plea for those who do like to talk about FEC to tell me what name this technique actually is.

k-Bit Brute Forcing Given that the output Vector s non-zero bit pattern is set due to the position of errors in the message vector, let s use that fact to build up a table of k-Bit errors that we can index into.
 // for clarity's sake, the Vector
 // type is being used as the lookup
 // key here, even though it may
 // need to be a hash or string in
 // some cases.
 idx := map[Vector]int 
for i := 0; i < N; i++  
// Create a vector of length N
 v := Vector 
v.FlipBit(i)
// Now, let's use the generator matrix to encode
 // the data with checksums, and then use the
 // check matrix on the message to figure out what
 // bit pattern results
 ev := Multiply(scheme.H, Multiply(v, scheme.G))
idx[ev] = i
 
This can be extended to multiple bits (hence: k-Bits), but I ve only done one here for illustration. Now that we have our idx mapping, we can now go back to the hot path on Checking the incoming message data:
 // if the ch vector is all zeros, we know
 // that the message is valid, and we don't
 // need to do anything.
 if ch.IsZero()  
// handle the case where the message
 // is fine as-is.
 return ...
 
errIdx, ok := idx[ch]
if ok  
msg.FlipBit(errIdx)
// Verify the LDPC message using
 // H again here.
 return ...
 
// Expensive decode here
Since map lookups wind up a heck of a lot faster than message-passing bit state, the hope here is this will short-circuit easy to solve errors for k-Bits, for some value of k that the system memory can tolerate.

Does this work? Frankly I have no idea. I ve written a small program and brute forced single-bit errors in all bit positions using random data to start with, and I ve not been able to find any collisions in the 1-bit error set, using the LDPC matrix from 802.3an-2006. Even if I was to find a collision for a higher-order k-Bit value, I m tempted to continue with this approach, and treat each set of bits in the Vector s bin (like a hash-table), checking the LDPC validity after each bit set in the bin. As long as the collision rate is small enough, it should be possible to correct k-Bits of error faster than the more expensive Belief Propagation approach. That being said, I m not entirely convinced collisions will be very common, but it ll take a bit more time working through the math to say that with any confidence. Have you seen this approach called something official in publications? See an obvious flaw in the system? Send me a tip, please!

Jonathan Dowland: Halloween playlist 2022

I hope you had a nice Halloween! I've collected together some songs that I've enjoyed over the last couple of years that loosely fit a theme: ambient, instrumental, experimental, industrial, dark, disconcerting, etc. I've prepared a Spotify playlist of most of them, but not all. The list is inline below as well, with many (but not all) tracks linking to Bandcamp, if I could find them there. This is a bit late, sorry. If anyone listens to something here and has any feedback I'd love to hear it. (If you are reading this on an aggregation site, it's possible the embeds won't work. If so, click through to my main site) Spotify playlist: https://open.spotify.com/playlist/3bEvEguRnf9U1RFrNbv5fk?si=9084cbf78c364ac8; The list, with Bandcamp embeds where possible: Some sources
  1. Via Stuart Maconie's Freak Zone
  2. Via Mary Anne Hobbs
  3. Via Lose yourself with
  4. Soma FM - Doomed (Halloween Special)

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