Search Results: "chr"

25 January 2024

Dirk Eddelbuettel: qlcal 0.0.10 on CRAN: Calendar Updates

The tenth release of the qlcal package arrivied at CRAN today. qlcal delivers the calendaring parts of QuantLib. It is provided (for the R package) as a set of included files, so the package is self-contained and does not depend on an external QuantLib library (which can be demanding to build). qlcal covers over sixty country / market calendars and can compute holiday lists, its complement (i.e. business day lists) and much more. Examples are in the README at the repository, the package page, and course at the CRAN package page. This releases synchronizes qlcal with the QuantLib release 1.33 and its updates to 2024 calendars.

Changes in version 0.0.10 (2024-01-24)
  • Synchronized with QuantLib 1.33

Courtesy of my CRANberries, there is a diffstat report for this release. See the project page and package documentation for more details, and more examples. If you like this or other open-source work I do, you can now sponsor me at GitHub.

This post by Dirk Eddelbuettel originated on his Thinking inside the box blog. Please report excessive re-aggregation in third-party for-profit settings.

24 January 2024

Thomas Lange: FAI 6.2 released

After more than one a year, a new minor FAI version is available, but it includes some interesting new features. Here a the items from the NEWS file: fai (6.2) unstable; urgency=low In the past the command fai-cd was only used for creating installation ISOs, that could be used from CD or USB stick. Now it possible to create a live ISO. Therefore you create your live chroot environment using 'fai dirinstall' and then convert it to a bootable live ISO using fai-cd. See man fai-cd(8) for an example. Years ago I had the idea to use the remaining disk space on an USB stick after copying an ISO onto it. I've blogged about this recently: https://blog.fai-project.org/posts/extending-iso-images/ The new FAI version includes the tool mk-data-partition for adding a data partition to the ISO itself or to an USB stick. FAI detects this data partition, mounts it to /media/data and can then use various configurations from it. You may want to copy your own set of .deb packages or your whole FAI config space to this partition. FAI now automatically searches this partition for usable FAI configuration data and packages. FAI will install all packages from pkgs/<CLASSNAME> if the equivalent class is defined. Setting FAI_CONFIG_SRC=detect:// now looks into the data partition for the subdirectory 'config' and uses this as the config space. So it's now possible to modify an existing ISO (that is read-only) and make changes to the config space. If there's no config directory in the data partition FAI uses the default location on the ISO. The tool fai-kvm, which starts virtual machines can now boot an ISO not only as CD but also as USB stick. Sometimes users want to adjust the list of disks before the partitioning is startet. Therefore FAI provides several new functions including You can select individual disks by their model name or even the serial number. Two new FAI flags were added (tmux and screen) that make it easy to run FAI inside a tmux or screen session. And finally FAI uses systemd. Yeah! This technical change was waiting since 2015 in a merge request from Moritz 'Morty' Str be, that would enable using systemd during the installation. Before FAI still was using old-style SYSV init scripts and did not started systemd. I didn't tried to apply the patch, because I was afraid that it would need much time to make it work. But then in may 2023 Juri Grabowski just gave it a try at MiniDebConf Hamburg, and voil it just works! Many, many thanks to Moritz and Juri for their bravery. The whole changelog can be found at https://tracker.debian.org/media/packages/f/fai/changelog-6.2 New ISOs for FAI are also available including an example of a Xfce desktop live ISO: https://fai-project.org/fai-cd/ The FAIme service for creating customized installation ISOs will get its update later. The new packages are available for bookworm by adding this line to your sources.list: deb https://fai-project.org/download bookworm koeln

22 January 2024

Chris Lamb: Increasing the Integrity of Software Supply Chains awarded IEEE Best Paper award

IEEE Software recently announced that a paper that I co-authored with Dr. Stefano Zacchiroli has recently been awarded their Best Paper award:
Titled Reproducible Builds: Increasing the Integrity of Software Supply Chains, the abstract reads as follows:
Although it is possible to increase confidence in Free and Open Source Software (FOSS) by reviewing its source code, trusting code is not the same as trusting its executable counterparts. These are typically built and distributed by third-party vendors with severe security consequences if their supply chains are compromised. In this paper, we present reproducible builds, an approach that can determine whether generated binaries correspond with their original source code. We first define the problem and then provide insight into the challenges of making real-world software build in a "reproducible" manner that is, when every build generates bit-for-bit identical results. Through the experience of the Reproducible Builds project making the Debian Linux distribution reproducible, we also describe the affinity between reproducibility and quality assurance (QA).
According to Google Scholar, the paper has accumulated almost 40 citations since publication. The full text of the paper can be found in PDF format.

Paul Tagliamonte: Writing a simulator to check phased array beamforming

Interested in future updates? Follow me on mastodon at @paul@soylent.green. Posts about hz.tools will be tagged #hztools.

If you're on the Fediverse, I'd very much appreciate boosts on my toot!
While working on hz.tools, I started to move my beamforming code from 2-D (meaning, beamforming to some specific angle on the X-Y plane for waves on the X-Y plane) to 3-D. I ll have more to say about that once I get around to publishing the code as soon as I m sure it s not completely wrong, but in the meantime I decided to write a simple simulator to visually check the beamformer against the textbooks. The results were pretty rad, so I figured I d throw together a post since it s interesting all on its own outside of beamforming as a general topic. I figured I d write this in Rust, since I ve been using Rust as my primary language over at zoo, and it s a good chance to learn the language better.
This post has some large GIFs

It make take a little bit to load depending on your internet connection. Sorry about that, I'm not clever enough to do better without doing tons of complex engineering work. They may be choppy while they load or something. I tried to compress an ensmall them, so if they're loaded but fuzzy, click on them to load a slightly larger version.
This post won t cover the basics of how phased arrays work or the specifics of calculating the phase offsets for each antenna, but I ll dig into how I wrote a simple simulator and how I wound up checking my phase offsets to generate the renders below.

Assumptions I didn t want to build a general purpose RF simulator, anything particularly generic, or something that would solve for any more than the things right in front of me. To do this as simply (and quickly all this code took about a day to write, including the beamforming math) I had to reduce the amount of work in front of me. Given that I was concerend with visualizing what the antenna pattern would look like in 3-D given some antenna geometry, operating frequency and configured beam, I made the following assumptions: All anetnnas are perfectly isotropic they receive a signal that is exactly the same strength no matter what direction the signal originates from. There s a single point-source isotropic emitter in the far-field (I modeled this as being 1 million meters away 1000 kilometers) of the antenna system. There is no noise, multipath, loss or distortion in the signal as it travels through space. Antennas will never interfere with each other.

2-D Polar Plots The last time I wrote something like this, I generated 2-D GIFs which show a radiation pattern, not unlike the polar plots you d see on a microphone. These are handy because it lets you visualize what the directionality of the antenna looks like, as well as in what direction emissions are captured, and in what directions emissions are nulled out. You can see these plots on spec sheets for antennas in both 2-D and 3-D form. Now, let s port the 2-D approach to 3-D and see how well it works out.

Writing the 3-D simulator As an EM wave travels through free space, the place at which you sample the wave controls that phase you observe at each time-step. This means, assuming perfectly synchronized clocks, a transmitter and receiver exactly one RF wavelength apart will observe a signal in-phase, but a transmitter and receiver a half wavelength apart will observe a signal 180 degrees out of phase. This means that if we take the distance between our point-source and antenna element, divide it by the wavelength, we can use the fractional part of the resulting number to determine the phase observed. If we multiply that number (in the range of 0 to just under 1) by tau, we can generate a complex number by taking the cos and sin of the multiplied phase (in the range of 0 to tau), assuming the transmitter is emitting a carrier wave at a static amplitude and all clocks are in perfect sync.
 let observed_phases: Vec<Complex> = antennas
.iter()
.map( antenna   
let distance = (antenna - tx).magnitude();
let distance = distance - (distance as i64 as f64);
((distance / wavelength) * TAU)
 )
.map( phase  Complex(phase.cos(), phase.sin()))
.collect();
At this point, given some synthetic transmission point and each antenna, we know what the expected complex sample would be at each antenna. At this point, we can adjust the phase of each antenna according to the beamforming phase offset configuration, and add up every sample in order to determine what the entire system would collectively produce a sample as.
 let beamformed_phases: Vec<Complex> = ...;
let magnitude = beamformed_phases
.iter()
.zip(observed_phases.iter())
.map( (beamformed, observed)  observed * beamformed)
.reduce( acc, el  acc + el)
.unwrap()
.abs();
Armed with this information, it s straight forward to generate some number of (Azimuth, Elevation) points to sample, generate a transmission point far away in that direction, resolve what the resulting Complex sample would be, take its magnitude, and use that to create an (x, y, z) point at (azimuth, elevation, magnitude). The color attached two that point is based on its distance from (0, 0, 0). I opted to use the Life Aquatic table for this one. After this process is complete, I have a point cloud of ((x, y, z), (r, g, b)) points. I wrote a small program using kiss3d to render point cloud using tons of small spheres, and write out the frames to a set of PNGs, which get compiled into a GIF. Now for the fun part, let s take a look at some radiation patterns!

1x4 Phased Array The first configuration is a phased array where all the elements are in perfect alignment on the y and z axis, and separated by some offset in the x axis. This configuration can sweep 180 degrees (not the full 360), but can t be steared in elevation at all. Let s take a look at what this looks like for a well constructed 1x4 phased array: And now let s take a look at the renders as we play with the configuration of this array and make sure things look right. Our initial quarter-wavelength spacing is very effective and has some outstanding performance characteristics. Let s check to see that everything looks right as a first test. Nice. Looks perfect. When pointing forward at (0, 0), we d expect to see a torus, which we do. As we sweep between 0 and 360, astute observers will notice the pattern is mirrored along the axis of the antennas, when the beam is facing forward to 0 degrees, it ll also receive at 180 degrees just as strong. There s a small sidelobe that forms when it s configured along the array, but it also becomes the most directional, and the sidelobes remain fairly small.

Long compared to the wavelength (1 ) Let s try again, but rather than spacing each antenna of a wavelength apart, let s see about spacing each antenna 1 of a wavelength apart instead. The main lobe is a lot more narrow (not a bad thing!), but some significant sidelobes have formed (not ideal). This can cause a lot of confusion when doing things that require a lot of directional resolution unless they re compensated for.

Going from ( to 5 ) The last model begs the question - what do things look like when you separate the antennas from each other but without moving the beam? Let s simulate moving our antennas but not adjusting the configured beam or operating frequency. Very cool. As the spacing becomes longer in relation to the operating frequency, we can see the sidelobes start to form out of the end of the antenna system.

2x2 Phased Array The second configuration I want to try is a phased array where the elements are in perfect alignment on the z axis, and separated by a fixed offset in either the x or y axis by their neighbor, forming a square when viewed along the x/y axis. Let s take a look at what this looks like for a well constructed 2x2 phased array: Let s do the same as above and take a look at the renders as we play with the configuration of this array and see what things look like. This configuration should suppress the sidelobes and give us good performance, and even give us some amount of control in elevation while we re at it. Sweet. Heck yeah. The array is quite directional in the configured direction, and can even sweep a little bit in elevation, a definite improvement from the 1x4 above.

Long compared to the wavelength (1 ) Let s do the same thing as the 1x4 and take a look at what happens when the distance between elements is long compared to the frequency of operation say, 1 of a wavelength apart? What happens to the sidelobes given this spacing when the frequency of operation is much different than the physical geometry? Mesmerising. This is my favorate render. The sidelobes are very fun to watch come in and out of existence. It looks absolutely other-worldly.

Going from ( to 5 ) Finally, for completeness' sake, what do things look like when you separate the antennas from each other just as we did with the 1x4? Let s simulate moving our antennas but not adjusting the configured beam or operating frequency. Very very cool. The sidelobes wind up turning the very blobby cardioid into an electromagnetic dog toy. I think we ve proven to ourselves that using a phased array much outside its designed frequency of operation seems like a real bad idea.

Future Work Now that I have a system to test things out, I m a bit more confident that my beamforming code is close to right! I d love to push that code over the line and blog about it, since it s a really interesting topic on its own. Once I m sure the code involved isn t full of lies, I ll put it up on the hztools org, and post about it here and on mastodon.

19 January 2024

Reproducible Builds (diffoscope): diffoscope 254 released

The diffoscope maintainers are pleased to announce the release of diffoscope version 254. This version includes the following changes:
[ Chris Lamb ]
* Reflow some code according to black.
[ Seth Michael Larson ]
* Add support for comparing the 'eXtensible ARchive' (.XAR/.PKG) file format.
[ Vagrant Cascadian ]
* Add external tool on GNU Guix for 7z.
You find out more by visiting the project homepage.

18 January 2024

Russell Coker: LicheePi 4A (RISC-V) First Look

I Just bought a LicheePi 4A RISC-V embedded computer (like a RaspberryPi but with a RISC-V CPU) for $322.68 from Aliexpress (the official site for buying LicheePi devices). Here is the Sipheed web page about it and their other recent offerings [1]. I got the version with 16G of RAM and 128G of storage, I probably don t need that much storage (I can use NFS or USB) but 16G of RAM is good for VMs. Here is the Wiki about this board [2]. Configuration When you get one of these devices you should make setting up ssh server your first priority. I found the HDMI output to be very unreliable. The first monitor I tried was a Samsung 4K monitor dating from when 4K was a new thing, the LicheePi initially refused to operate at a resolution higher than 1024*768 but later on switched to 4K resolution when resuming from screen-blank for no apparent reason (and the window manager didn t support this properly). On the Dell 4K monitor I use on my main workstation it sometimes refused to talk to it and occasionally worked. I got it running at 1920*1080 without problems and then switched it to 4K and it lost video sync and never talked to that monitor again. On my Desklab portabable 4K monitor I got it to display in 4K resolution but only the top left 1/4 of the screen displayed. The issues with HDMI monitor support greatly limit the immediate potential for using this as a workstation. It doesn t make it impossible but would be fiddly at best. It s quite likely that a future OS update will fix this. But at the moment it s best used as a server. The LicheePi has a custom Linux distribution based on Ubuntu so you want too put something like the following in /etc/network/interfaces to make it automatically connect to the ethernet when plugged in:
auto end0
iface end0 inet dhcp
Then to get sshd to start you have to run the following commands to generate ssh host keys that aren t zero bytes long:
rm /etc/ssh/ssh_host_*
systemctl restart ssh.service
It appears to have wifi hardware but the OS doesn t recognise it. This isn t a priority for me as I mostly want to use it as a server. Performance For the first test of performance I created a 100MB file from /dev/urandom and then tried compressing it on various systems. With zstd -9 it took 16.893 user seconds on the LicheePi4A, 0.428s on my Thinkpad X1 Carbon Gen5 with a i5-6300U CPU (Debian/Unstable), 1.288s on my E5-2696 v3 workstation (Debian/Bookworm), 0.467s on the E5-2696 v3 running Debian/Unstable, 2.067s on a E3-1271 v3 server, and 7.179s on the E3-1271 v3 system emulating a RISC-V system via QEMU running Debian/Unstable. It s very impressive that the QEMU emulation is fast enough that emulating a different CPU architecture is only 3.5* slower for this test (or maybe 10* slower if it was running Debian/Unstable on the AMD64 code)! The emulated RISC-V is also more than twice as fast as real RISC-V hardware and probably of comparable speed to real RISC-V hardware when running the same versions (and might be slightly slower if running the same version of zstd) which is a tribute to the quality of emulation. One performance issue that most people don t notice is the time taken to negotiate ssh sessions. It s usually not noticed because the common CPUs have got faster at about the same rate as the algorithms for encryption and authentication have become more complex. On my i5-6300U laptop it takes 0m0.384s to run ssh -i ~/.ssh/id_ed25519 localhost id with the below server settings (taken from advice on ssh-audit.com [3] for a secure ssh configuration). On the E3-1271 v3 server it is 0.336s, on the QMU system it is 28.022s, and on the LicheePi it is 0.592s. By this metric the LicheePi is about 80% slower than decent x86 systems and the QEMU emulation of RISC-V is 73* slower than the x86 system it runs on. Does crypto depend on instructions that are difficult to emulate?
HostKey /etc/ssh/ssh_host_ed25519_key
KexAlgorithms -ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group14-sha256
MACs -umac-64-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
I haven t yet tested the performance of Ethernet (what routing speed can you get through the 2 gigabit ports?), emmc storage, and USB. At the moment I ve been focused on using RISC-V as a test and development platform. My conclusion is that I m glad I don t plan to compile many kernels or anything large like LibreOffice. But that for typical development that I do it will be quite adequate. The speed of Chromium seems adequate in basic tests, but the video output hasn t worked reliably enough to do advanced tests. Hardware Features Having two Gigabit Ethernet ports, 4 USB-3 ports, and Wifi on board gives some great options for using this as a router. It s disappointing that they didn t go with 2.5Gbit as everyone seems to be doing that nowadays but Gigabit is enough for most things. Having only a single HDMI port and not supporting USB-C docks (the USB-C port appears to be power only) limits what can be done for workstation use and for controlling displays. I know of people using small ARM computers attached to the back of large TVs for advertising purposes and that isn t going to be a great option for this. The CPU and RAM apparently uses a lot of power (which is relative the entire system draws up to 2A at 5V so the CPU would be something below 5W). To get this working a cooling fan has to be stuck to the CPU and RAM chips via a layer of thermal stuff that resembles a fine sheet of blu-tack in both color and stickyness. I am disappointed that there isn t any more solid form of construction, to mount this on a wall or ceiling some extra hardware would be needed to secure this. Also if they just had a really big copper heatsink I think that would be better. 80386 CPUs with similar TDP were able to run without a fan. I wonder how things would work with all USB ports in use. It s expected that a USB port can supply a minimum of 2.5W which means that all the ports could require 10W if they were active. Presumably something significantly less than 5W is available for the USB ports. Other Devices Sipheed has a range of other devices in the works. They currently sell the LicheeCluster4A which support 7 compute modules for a cluster in a box. This has some interesting potential for testing and demonstrating cluster software but you could probably buy an AMD64 system with more compute power for less money. The Lichee Console 4A is a tiny laptop which could be useful for people who like the 7 laptop form factor, unfortunately it only has a 1280*800 display if it had the same resolution display as a typical 7 phone I would have bought one. The next device that appeals to me is the soon to be released Lichee Pad 4A which is a 10.1 tablet with 1920*1200 display, Wifi6, Bluetooth 5.4, and 16G of RAM. It also has 1 USB-C connection, 2*USB-3 sockets, and support for an external card with 2*Gigabit ethernet. It s a tablet as a laptop without keyboard instead of the more common larger phone design model. They are also about to release the LicheePadMax4A which is similar to the other tablet but with a 14 2240*1400 display and which ships with a keyboard to make it essentially a laptop with detachable keyboard. Conclusion At this time I wouldn t recommend that this device be used as a workstation or laptop, although the people who want to do such things will probably do it anyway regardless of my recommendations. I think it will be very useful as a test system for RISC-V development. I have some friends who are interested in this sort of thing and I can give them VMs. It is a bit expensive. The Sipheed web site boasts about the LicheePi4 being faster than the RaspberryPi4, but it s not a lot faster and the RaspberryPi4 is much cheaper ($127 or $129 for one with 8G of RAM). The RaspberryPi4 has two HDMI ports but a limit of 8G of RAM while the LicheePi has up to 16G of RAM and two Gigabit Ethernet ports but only a single HDMI port. It seems that the RaspberryPi4 might win if you want a cheap low power desktop system. At this time I think the reason for this device is testing out RISC-V as an alternative to the AMD64 and ARM64 architectures. An open CPU architecture goes well with free software, but it isn t just people who are into FOSS who are testing such things. I know some corporations are trying out RISC-V as a way of getting other options for embedded systems that don t involve paying monopolists. The Lichee Console 4A is probably a usable tiny laptop if the resolution is sufficient for your needs. As an aside I predict that the tiny laptop or pocket computer segment will take off in the near future. There are some AMD64 systems the size of a phone but thicker that run Windows and go for reasonable prices on AliExpress. Hopefully in the near future this device will have better video drivers and be usable as a small and quiet workstation. I won t rule out the possibility of making this my main workstation in the not too distant future, all it needs is reliable 4K display and the ability to decode 4K video. It s performance for web browsing and as an ssh client seems adequate, and that s what matters for my workstation use. But for the moment it s just for server use.

15 January 2024

Colin Watson: OpenUK New Year s Honours

Apparently I got an honour from OpenUK. There are a bunch of people I know on that list. Chris Lamb and Mark Brown are familiar names from Debian. Colin King and Jonathan Riddell are people I know from past work in Ubuntu. I ve admired David MacIver s work on Hypothesis and Richard Hughes work on firmware updates from afar. And there are a bunch of other excellent projects represented there: OpenStreetMap, Textualize, and my alma mater of Cambridge to name but a few. My friend Stuart Langridge wrote about being on a similar list a few years ago, and I can t do much better than to echo it: in particular he wrote about the way the open source development community is often at best unwelcoming to people who don t look like Stuart and I do. I can t tell a whole lot about demographic distribution just by looking at a list of names, but while these honours still seem to be skewed somewhat male, I m fairly sure they re doing a lot better in terms of gender balance than my home project of Debian is, for one. I hope this is a sign of improvement for the future, and I ll do what I can to pay it forward.

13 January 2024

Freexian Collaborators: Debian Contributions: LXD/Incus backend bug, /usr-merge updates, gcc-for-host, and more! (by Utkarsh Gupta)

Contributing to Debian is part of Freexian s mission. This article covers the latest achievements of Freexian and their collaborators. All of this is made possible by organizations subscribing to our Long Term Support contracts and consulting services.

LXD/Incus backend bug in autopkgtest by Stefano Rivera While working on the Python 3.12 transition, Stefano repeatedly ran into a bug in autopkgtest when using LXD (or in the future Incus), that caused it to hang when running cython s multi-hour autopkgtests. After some head-banging, the bug turned out to be fairly straightforward: LXD didn t shut down on receiving a SIGTERM, so when a testsuite timed out, it would hang forever. A simple fix has been applied.

/usr-merge, by Helmut Grohne Thanks to Christian Hofstaedtler and others, the effort is moving into a community effort and the work funded by Freexian becomes more difficult to separate from non-funded work. In particular, since the community fully handled all issues around lost udev rules, dh_installudev now installs rules to /usr. The story around diversions took another detour. We learned that conflicts do not reliably prevent concurrent unpack and the reiterated mitigation for molly-guard triggered this. After a bit of back and forth and consultation with the developer mailing list, we concluded that avoiding the problematic behavior when using apt or an apt-based upgrader combined with a loss mitigation would be good enough. The involved packages bfh-container, molly-guard, progress-linux-container and systemd have since been uploaded to unstable and the matter seems finally solved except that it doesn t quite work with sysvinit yet. The same approach is now being proposed for the diversions of zutils for gzip. We thank involved maintainers for their timely cooperation.

gcc-for-host, by Helmut Grohne Since forever, it has been difficult to correctly express a toolchain build dependency. This can be seen in the Build-Depends of the linux source package for instance. While this has been solved for binutils a while back, the patches for gcc have been unfinished. With lots of constructive feedback from gcc package maintainer Matthias Klose, Helmut worked on finalizing and testing these patches. Patch stacks are now available for gcc-13 and gcc-14 and Matthias already included parts of them in test builds for Ubuntu noble. Finishing this work would enable us to resolve around 1000 cross build dependency satisfiability issues in unstable.

Miscellaneous contributions
  • Stefano continued work on the Python 3.12 transition, including uploads of cython, pycxx, numpy, python-greenlet, twisted, foolscap and dh-python.
  • Stefano reviewed and selected from a new round of DebConf 24 bids, as part of the DebConf Committee. Busan, South Korea was selected.
  • For debian-printing Thorsten uploaded hplip to unstable to fix a /usr-merge bug and cups to Bookworm to fix bugs related to printing in color.
  • Utkarsh helped newcomers in mentoring and reviewing their packaging; eg: golang-github-prometheus-community-pgbouncer-exporter.
  • Helmut sent patches for 42 cross build failures unrelated to the gcc-for-host work.
  • Helmut continues to maintain rebootstrap. In December, blt started depending on libjpeg and this poses a dependency loop. Ideally, Python would stop depending on blt. Also linux-libc-dev having become Multi-Arch: foreign poses non-trivial issues that are not fully resolved yet.
  • Enrico participated in /usr-merge discussions with Helmut.

12 January 2024

Freexian Collaborators: Monthly report about Debian Long Term Support, December 2023 (by Roberto C. S nchez)

Like each month, have a look at the work funded by Freexian s Debian LTS offering.

Debian LTS contributors In December, 18 contributors have been paid to work on Debian LTS, their reports are available:
  • Abhijith PA did 7.0h (out of 7.0h assigned and 7.0h from previous period), thus carrying over 7.0h to the next month.
  • Adrian Bunk did 16.0h (out of 26.25h assigned and 8.75h from previous period), thus carrying over 19.0h to the next month.
  • Bastien Roucari s did 16.0h (out of 16.0h assigned and 4.0h from previous period), thus carrying over 4.0h to the next month.
  • Ben Hutchings did 8.0h (out of 7.25h assigned and 16.75h from previous period), thus carrying over 16.0h to the next month.
  • Chris Lamb did 18.0h (out of 18.0h assigned).
  • Emilio Pozuelo Monfort did 8.0h (out of 26.75h assigned and 8.25h from previous period), thus carrying over 27.0h to the next month.
  • Guilhem Moulin did 25.0h (out of 18.0h assigned and 7.0h from previous period).
  • Holger Levsen did 5.5h (out of 5.5h assigned).
  • Jochen Sprickerhof did 0.0h (out of 0h assigned and 10.0h from previous period), thus carrying over 10.0h to the next month.
  • Lee Garrett did 0.0h (out of 25.75h assigned and 9.25h from previous period), thus carrying over 35.0h to the next month.
  • Markus Koschany did 35.0h (out of 35.0h assigned).
  • Roberto C. S nchez did 9.5h (out of 5.5h assigned and 6.5h from previous period), thus carrying over 2.5h to the next month.
  • Santiago Ruano Rinc n did 8.255h (out of 3.26h assigned and 12.745h from previous period), thus carrying over 7.75h to the next month.
  • Sean Whitton did 4.25h (out of 3.25h assigned and 6.75h from previous period), thus carrying over 5.75h to the next month.
  • Sylvain Beucler did 16.5h (out of 21.25h assigned and 13.75h from previous period), thus carrying over 18.5h to the next month.
  • Thorsten Alteholz did 14.0h (out of 14.0h assigned).
  • Tobias Frost did 10.25h (out of 12.0h assigned), thus carrying over 1.75h to the next month.
  • Utkarsh Gupta did 18.75h (out of 11.25h assigned and 13.5h from previous period), thus carrying over 6.0h to the next month.

Evolution of the situation In December, we have released 29 DLAs. A particularly notable update in December was prepared by LTS contributor Santiago Ruano Rinc n for the openssh package. The updated produced DLA-3694-1 and included a fix for the Terrapin Attack (CVE-2023-48795), which was a rather serious flaw in the SSH protocol itself. The package bluez was the subject of another notable update by LTS contributor Chris Lamb, which resulted in DLA-3689-1 to address an insecure default configuration which allowed attackers to inject keyboard commands over Bluetooth without first authenticating. The LTS team continues its efforts to have a positive impact beyond the boundaries of LTS. Several contributors worked on packages, preparing LTS updates, but also preparing patches or full updates which were uploaded to the unstable, stable, and oldstable distributions, including: Guilhem Moulin s update of tinyxml (uploads to LTS and unstable and patches submitted to the security team for stable and oldstable); Guilhem Moulin s update of xerces-c (uploads to LTS and unstable and patches submitted to the security team for oldstable); Thorsten Alteholz s update of libde265 (uploads to LTS and stable and additional patches submitted to the maintainer for stable and oldstable); Thorsten Alteholz s update of cjson (upload to LTS and patches submitted to the maintainer for stable and oldstable); and Tobias Frost s update of opendkim (sponsor maintainer-prepared upload to LTS and additionally prepared updates for stable and oldstable). Going beyond Debian and looking to the broader community, LTS contributor Bastien Roucari s was contacted by SUSE concerning an update he had prepared for zbar. He was able to assist by coordinating with the former organization of the original zbar author to secure for SUSE access to information concerning the exploits. This has enabled another distribution to benefit from the work done in support of LTS and from the assistance of Bastien in coordinating the access to information. Finally, LTS contributor Santiago Ruano Rinc n continued work relating to how updates for packages in statically-linked language ecosystems (e.g., Go, Rust, and others) are handled. The work is presently focused on more accurately and reliably identifying which packages are impacted in a given update scenario to enable notifications to be published so that users will be made aware of these situations as they occur. As the work continues, it will eventually result in improvements to Debian infrustructure so that the LTS team and Security team are able to manage updates of this nature in a more consistent way.

Thanks to our sponsors Sponsors that joined recently are in bold.

11 January 2024

Reproducible Builds: Reproducible Builds in December 2023

Welcome to the December 2023 report from the Reproducible Builds project! In these reports we outline the most important things that we have been up to over the past month. As a rather rapid recap, whilst anyone may inspect the source code of free software for malicious flaws, almost all software is distributed to end users as pre-compiled binaries (more).

Reproducible Builds: Increasing the Integrity of Software Supply Chains awarded IEEE Software Best Paper award In February 2022, we announced in these reports that a paper written by Chris Lamb and Stefano Zacchiroli was now available in the March/April 2022 issue of IEEE Software. Titled Reproducible Builds: Increasing the Integrity of Software Supply Chains (PDF). This month, however, IEEE Software announced that this paper has won their Best Paper award for 2022.

Reproducibility to affect package migration policy in Debian In a post summarising the activities of the Debian Release Team at a recent in-person Debian event in Cambridge, UK, Paul Gevers announced a change to the way packages are migrated into the staging area for the next stable Debian release based on its reproducibility status:
The folks from the Reproducibility Project have come a long way since they started working on it 10 years ago, and we believe it s time for the next step in Debian. Several weeks ago, we enabled a migration policy in our migration software that checks for regression in reproducibility. At this moment, that is presented as just for info, but we intend to change that to delays in the not so distant future. We eventually want all packages to be reproducible. To stimulate maintainers to make their packages reproducible now, we ll soon start to apply a bounty [speedup] for reproducible builds, like we ve done with passing autopkgtests for years. We ll reduce the bounty for successful autopkgtests at that moment in time.

Speranza: Usable, privacy-friendly software signing Kelsey Merrill, Karen Sollins, Santiago Torres-Arias and Zachary Newman have developed a new system called Speranza, which is aimed at reassuring software consumers that the product they are getting has not been tampered with and is coming directly from a source they trust. A write-up on TechXplore.com goes into some more details:
What we have done, explains Sollins, is to develop, prove correct, and demonstrate the viability of an approach that allows the [software] maintainers to remain anonymous. Preserving anonymity is obviously important, given that almost everyone software developers included value their confidentiality. This new approach, Sollins adds, simultaneously allows [software] users to have confidence that the maintainers are, in fact, legitimate maintainers and, furthermore, that the code being downloaded is, in fact, the correct code of that maintainer. [ ]
The corresponding paper is published on the arXiv preprint server in various formats, and the announcement has also been covered in MIT News.

Nondeterministic Git bundles Paul Baecher published an interesting blog post on Reproducible git bundles. For those who are not familiar with them, Git bundles are used for the offline transfer of Git objects without an active server sitting on the other side of a network connection. Anyway, Paul wrote about writing a backup system for his entire system, but:
I noticed that a small but fixed subset of [Git] repositories are getting backed up despite having no changes made. That is odd because I would think that repeated bundling of the same repository state should create the exact same bundle. However [it] turns out that for some, repositories bundling is nondeterministic.
Paul goes on to to describe his solution, which involves forcing git to be single threaded makes the output deterministic . The article was also discussed on Hacker News.

Output from libxlst now deterministic libxslt is the XSLT C library developed for the GNOME project, where XSLT itself is an XML language to define transformations for XML files. This month, it was revealed that the result of the generate-id() XSLT function is now deterministic across multiple transformations, fixing many issues with reproducible builds. As the Git commit by Nick Wellnhofer describes:
Rework the generate-id() function to return deterministic values. We use
a simple incrementing counter and store ids in the 'psvi' member of
nodes which was freed up by previous commits. The presence of an id is
indicated by a new "source node" flag.
This fixes long-standing problems with reproducible builds, see
https://bugzilla.gnome.org/show_bug.cgi?id=751621
This also hardens security, as the old implementation leaked the
difference between a heap and a global pointer, see
https://bugs.chromium.org/p/chromium/issues/detail?id=1356211
The old implementation could also generate the same id for dynamically
created nodes which happened to reuse the same memory. Ids for namespace
nodes were completely broken. They now use the id of the parent element
together with the hex-encoded namespace prefix.

Community updates There were made a number of improvements to our website, including Chris Lamb fixing the generate-draft script to not blow up if the input files have been corrupted today or even in the past [ ], Holger Levsen updated the Hamburg 2023 summit to add a link to farewell post [ ] & to add a picture of a Post-It note. [ ], and Pol Dellaiera updated the paragraph about tar and the --clamp-mtime flag [ ]. On our mailing list this month, Bernhard M. Wiedemann posted an interesting summary on some of the reasons why packages are still not reproducible in 2023. diffoscope is our in-depth and content-aware diff utility that can locate and diagnose reproducibility issues. This month, Chris Lamb made a number of changes, including processing objdump symbol comment filter inputs as Python byte (and not str) instances [ ] and Vagrant Cascadian extended diffoscope support for GNU Guix [ ] and updated the version in that distribution to version 253 [ ].

Challenges of Producing Software Bill Of Materials for Java Musard Balliu, Benoit Baudry, Sofia Bobadilla, Mathias Ekstedt, Martin Monperrus, Javier Ron, Aman Sharma, Gabriel Skoglund, C sar Soto-Valero and Martin Wittlinger (!) of the KTH Royal Institute of Technology in Sweden, have published an article in which they:
deep-dive into 6 tools and the accuracy of the SBOMs they produce for complex open-source Java projects. Our novel insights reveal some hard challenges regarding the accurate production and usage of software bills of materials.
The paper is available on arXiv.

Debian Non-Maintainer campaign As mentioned in previous reports, the Reproducible Builds team within Debian has been organising a series of online and offline sprints in order to clear the huge backlog of reproducible builds patches submitted by performing so-called NMUs (Non-Maintainer Uploads). During December, Vagrant Cascadian performed a number of such uploads, including: In addition, Holger Levsen performed three no-source-change NMUs in order to address the last packages without .buildinfo files in Debian trixie, specifically lorene (0.0.0~cvs20161116+dfsg-1.1), maria (1.3.5-4.2) and ruby-rinku (1.7.3-2.1).

Reproducibility 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 December, a number of changes were made by Holger Levsen:
  • Debian-related changes:
    • Fix matching packages for the [R programming language](https://en.wikipedia.org/wiki/R_(programming_language). [ ][ ][ ]
    • Add a Certbot configuration for the Nginx web server. [ ]
    • Enable debugging for the create-meta-pkgs tool. [ ][ ]
  • Arch Linux-related changes
    • The asp has been deprecated by pkgctl; thanks to dvzrv for the pointer. [ ]
    • Disable the Arch Linux builders for now. [ ]
    • Stop referring to the /trunk branch / subdirectory. [ ]
    • Use --protocol https when cloning repositories using the pkgctl tool. [ ]
  • Misc changes:
    • Install the python3-setuptools and swig packages, which are now needed to build OpenWrt. [ ]
    • Install pkg-config needed to build Coreboot artifacts. [ ]
    • Detect failures due to an issue where the fakeroot tool is implicitly required but not automatically installed. [ ]
    • Detect failures due to rename of the vmlinuz file. [ ]
    • Improve the grammar of an error message. [ ]
    • Document that freebsd-jenkins.debian.net has been updated to FreeBSD 14.0. [ ]
In addition, node maintenance was performed by Holger Levsen [ ] and Vagrant Cascadian [ ].

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:

If you are interested in contributing to the Reproducible Builds project, please visit our Contribute page on our website. However, you can get in touch with us via:

8 January 2024

Antoine Beaupr : Last year on this blog

So this blog is now celebrating its 21st birthday (or 20 if you count from zero, or 18 if you want to be pedantic), and I figured I would do this yearly thing of reviewing how that went.

Number of posts 2022 was the official 20th anniversary in any case, and that was one of my best years on record, with 46 posts, surpassed only by the noisy 2005 (62) and matching 2006 (46). 2023, in comparison, was underwhelming: a feeble 11 posts! What happened! Well, I was busy with other things, mostly away from keyboard, that I will not bore you with here... The other thing that happened is that the one-liner I used to collect stats was broken (it counted folders and other unrelated files) and wildly overestimated 2022! Turns out I didn't write that much then:
anarc.at$ ls blog   grep '^[0-9][0-9][0-9][0-9].*.md'   se
d s/-.*//   sort   uniq -c    sort -n -k2
     57 2005
     43 2006
     20 2007
     20 2008
      7 2009
     13 2010
     16 2011
     11 2012
     13 2013
      5 2014
     13 2015
     18 2016
     29 2017
     27 2018
     17 2019
     18 2020
     14 2021
     28 2022
     10 2023
      1 2024
But even that is inaccurate because, in ikiwiki, I can tag any page as being featured on the blog. So we actually need to process the HTML itself because we don't have much better on hand without going through ikiwiki's internals:
anarcat@angela:anarc.at$ curl -sSL https://anarc.at/blog/   grep 'href="\./'   grep -o 20[0-9][0-9]   sort   uniq -c 
     56 2005
     42 2006
     19 2007
     18 2008
      6 2009
     12 2010
     15 2011
     10 2012
     11 2013
      3 2014
     15 2015
     32 2016
     50 2017
     37 2018
     19 2019
     19 2020
     15 2021
     28 2022
     13 2023
Which puts the top 10 years at:
$ curl -sSL https://anarc.at/blog/   grep 'href="\./'   grep -o 20[0-9][0-9]   sort   uniq -c    sort -nr   head -10
     56 2005
     50 2017
     42 2006
     37 2018
     32 2016
     28 2022
     19 2020
     19 2019
     19 2007
     18 2008
Anyway. 2023 is certainly not a glorious year in that regard, in any case.

Visitors In terms of visits, however, we had quite a few hits. According to Goatcounter, I had 122 300 visits in 2023! 2022, in comparison, had 89 363, so that's quite a rise.

What you read I seem to have hit the Hacker News front page at least twice. I say "seem" because it's actually pretty hard to tell what the HN frontpage actually is on any given day. I had 22k visits on 2023-03-13, in any case, and you can't see me on the front that day. We do see a post of mine on 2023-09-02, all the way down there, which seem to have generated another 10k visits. In any case, here were the most popular stories for you fine visitors:
  • Framework 12th gen laptop review: 24k visits, which is surprising for a 13k words article "without images", as some critics have complained. 15k referred by Hacker News. Good reference and time-consuming benchmarks, slowly bit-rotting. That is, by far, my most popular article ever. A popular article in 2021 or 2022 was around 6k to 9k, so that's a big one. I suspect it will keep getting traffic for a long while.
  • Calibre replacement considerations: 15k visits, most of which without a referrer. Was actually an old article, but I suspect HN brought it back to light. I keep updating that wiki page regularly when I find new things, but I'm still using Calibre to import ebooks.
  • Hacking my Kobo Clara HD: is not new but always gathering more and more hits, it had 1800 hits in the first year, 4600 hits last year and now brought 6400 visitors to the blog! Not directly related, but this iFixit battery replacement guide I wrote also seem to be quite popular
Everything else was published before 2023. Replacing Smokeping with Prometheus is still around and Looking at Wayland terminal emulators makes an entry in the top five.

Where you've been People send less and less private information when they browse the web. The number of visitors without referrers was 41% in 2021, it rose to 44% in 2023. Most of the remaining traffic comes from Google, but Hacker News is now a significant chunk, almost as big as Google. In 2021, Google represented 23% of my traffic, in 2022, it was down to 15% so 18% is actually a rise from last year, even if it seems much smaller than what I usually think of.
Ratio Referrer Visits
18% Google 22 098
13% Hacker News 16 003
2% duckduckgo.com 2 640
1% community.frame.work 1 090
1% missing.csail.mit.edu 918
Note that Facebook and Twitter do not appear at all in my referrers.

Where you are Unsurprisingly, most visits still come from the US:
Ratio Country Visits
26% United States 32 010
14% France 17 046
10% Germany 11 650
6% Canada 7 425
5% United Kingdom 6 473
3% Netherlands 3 436
Those ratios are nearly identical to last year, but quite different from 2021, where Germany and France were more or less reversed. Back in 2021, I mentioned there was a long tail of countries with at least one visit, with 160 countries listed. I expanded that and there's now 182 countries in that list, almost all of the 193 member states in the UN.

What you were Chrome's dominance continues to expand, even on readers of this blog, gaining two percentage points from Firefox compared to 2021.
Ratio Browser Visits
49% Firefox 60 126
36% Chrome 44 052
14% Safari 17 463
1% Others N/A
It seems like, unfortunately, my Lynx and Haiku users have not visited in the past year. It seems like trying to read those metrics is like figuring out tea leaves... In terms of operating systems:
Ratio OS Visits
28% Linux 34 010
23% macOS 28 728
21% Windows 26 303
17% Android 20 614
10% iOS 11 741
Again, Linux and Mac are over-represented, and Android and iOS are under-represented.

What is next I hope to write more next year. I've been thinking about a few posts I could write for work, about how things work behind the scenes at Tor, that could be informative for many people. We run a rather old setup, but things hold up pretty well for what we throw at it, and it's worth sharing that with the world... So anyway, thanks for coming, faithful reader, and see you in the coming 2024 year...

7 January 2024

Valhalla's Things: A Corset or Two

Posted on January 7, 2024
Tags: madeof:atoms, craft:sewing, period:victorian, FreeSoftWear
a black coutil midbust corset, from a 3/4 front view, showing the busk closure, a waist tape and external boning channels made of the same twill tape and placed about 1-2 cm from each other at waist level. CW for body size change mentions I needed a corset, badly. Years ago I had a chance to have my measurements taken by a former professional corset maker and then a lesson in how to draft an underbust corset, and that lead to me learning how nice wearing a well-fitted corset feels. Later I tried to extend that pattern up for a midbust corset, with success. And then my body changed suddenly, and I was no longer able to wear either of those, and after a while I started missing them. Since my body was still changing (if no longer drastically so), and I didn t want to use expensive materials for something that had a risk of not fitting after too little time, I decided to start by making myself a summer lightweight corset in aida cloth and plastic boning (for which I had already bought materials). It fitted, but not as well as the first two ones, and I ve worn it quite a bit. I still wanted back the feeling of wearing a comfy, heavy contraption of coutil and steel, however. After a lot of procrastination I redrafted a new pattern, scrapped everything, tried again, had my measurements taken by a dressmaker [#dressmaker], put them in the draft, cut a first mock-up in cheap cotton, fixed the position of a seam, did a second mock-up in denim [#jeans] from an old pair of jeans, and then cut into the cheap herringbone coutil I was planning to use. And that s when I went to see which one of the busks in my stash would work, and realized that I had used a wrong vertical measurement and the front of the corset was way too long for a midbust corset. a corset busk basted to a mock-up with scraps of fabric between each stud / loop. Luckily I also had a few longer busks, I basted one to the denim mock up and tried to wear it for a few hours, to see if it was too long to be comfortable. It was just a bit, on the bottom, which could be easily fixed with the Power Tools1. Except, the more I looked at it the more doing this felt wrong: what I needed most was a midbust corset, not an overbust one, which is what this was starting to be. I could have trimmed it down, but I knew that I also wanted this corset to be a wearable mockup for the pattern, to refine it and have it available for more corsets. And I still had more than half of the cheap coutil I was using, so I decided to redo the pattern and cut new panels. And this is where the or two comes in: I m not going to waste the overbust panels: I had been wanting to learn some techniques to make corsets with a fashion fabric layer, rather than just a single layer of coutil, and this looks like an excellent opportunity for that, together with a piece of purple silk that I know I have in the stash. This will happen later, however, first I m giving priority to the underbust. Anyway, a second set of panels was cut, all the seam lines marked with tailor tacks, and I started sewing by inserting the busk. And then realized that the pre-made boning channel tape I had was too narrow for the 10 mm spiral steel I had plenty of. And that the 25 mm twill tape was also too narrow for a double boning channel. On the other hand, the 18 mm twill tape I had used for the waist tape was good for a single channel, so I decided to put a single bone on each seam, and then add another piece of boning in the middle of each panel. Since I m making external channels, making them in self fabric would have probably looked better, but I no longer had enough fabric, because of the cutting mishap, and anyway this is going to be a strictly underwear only corset, so it s not a big deal. Once the boning channel situation was taken care of, everything else proceeded quite smoothly and I was able to finish the corset during the Christmas break, enlisting again my SO to take care of the flat steel boning while I cut the spiral steels myself with wire cutters. The same corset straight from the front: the left side is a few mm longer than the right side I could have been a bit more precise with the binding, as it doesn t align precisely at the front edge, but then again, it s underwear, nobody other than me and everybody who reads this post is going to see it and I was in a hurry to see it finished. I will be more careful with the next one. The same corset from the back, showing cross lacing with bunny ears at the waist and a lacing gap of about 8 cm. I also think that I haven t been careful enough when pressing the seams and applying the tape, and I ve lost about a cm of width per part, so I m using a lacing gap that is a bit wider than I planned for, but that may change as the corset gets worn, and is still within tolerance. Also, on the morning after I had finished the corset I woke up and realized that I had forgotten to add garter tabs at the bottom edge. I don t know whether I will ever use them, but I wanted the option, so maybe I ll try to add them later on, especially if I can do it without undoing the binding. The next step would have been flossing, which I proceeded to postpone until I ve worn the corset for a while: not because there is any reason for it, but because I still don t know how I want to do it :) What was left was finishing and uploading the pattern and instructions, that are now on my sewing pattern website as #FreeSoftWear, and finally I could post this on the blog.

  1. i.e. by asking my SO to cut and sand it, because I m lazy and I hate doing that part :D

3 January 2024

John Goerzen: Live Migrating from Raspberry Pi OS bullseye to Debian bookworm

I ve been getting annoyed with Raspberry Pi OS (Raspbian) for years now. It s a fork of Debian, but manages to omit some of the most useful things. So I ve decided to migrate all of my Pis to run pure Debian. These are my reasons:
  1. Raspberry Pi OS has, for years now, specified that there is no upgrade path. That is, to get to a newer major release, it s a reinstall. While I have sometimes worked around this, for a device that is frequently installed in hard-to-reach locations, this is even more important than usual. It s common for me to upgrade machines for a decade or more across Debian releases and there s no reason that it should be so much more difficult with Raspbian.
  2. As I noted in Consider Security First, the security situation for Raspberry Pi OS isn t as good as it is with Debian.
  3. Raspbian lags behind Debian often times by 6 months or more for major releases, and days or weeks for bug fixes and security patches.
  4. Raspbian has no direct backports support, though Raspberry Pi 3 and above can use Debian s backports (per my instructions as Installing Debian Backports on Raspberry Pi)
  5. Raspbian uses a custom kernel without initramfs support
It turns out it is actually possible to do an in-place migration from Raspberry Pi OS bullseye to Debian bookworm. Here I will describe how. Even if you don t have a Raspberry Pi, this might still be instructive on how Raspbian and Debian packages work.

WARNINGS Before continuing, back up your system. This process isn t for the neophyte and it is entirely possible to mess up your boot device to the point that you have to do a fresh install to get your Pi to boot. This isn t a supported process at all.

Architecture Confusion Debian has three ARM-based architectures:
  • armel, for the lowest-end 32-bit ARM devices without hardware floating point support
  • armhf, for the higher-end 32-bit ARM devices with hardware float (hence hf )
  • arm64, for 64-bit ARM devices (which all have hardware float)
Although the Raspberry Pi 0 and 1 do support hardware float, they lack support for other CPU features that Debian s armhf architecture assumes. Therefore, the Raspberry Pi 0 and 1 could only run Debian s armel architecture. Raspberry Pi 3 and above are capable of running 64-bit, and can run both armhf and arm64. Prior to the release of the Raspberry Pi 5 / Raspbian bookworm, Raspbian only shipped the armhf architecture. Well, it was an architecture they called armhf, but it was different from Debian s armhf in that everything was recompiled to work with the more limited set of features on the earlier Raspberry Pi boards. It was really somewhere between Debian s armel and armhf archs. You could run Debian armel on those, but it would run more slowly, due to doing floating point calculations without hardware support. Debian s raspi FAQ goes into this a bit. What I am going to describe here is going from Raspbian armhf to Debian armhf with a 64-bit kernel. Therefore, it will only work with Raspberry Pi 3 and above. It may theoretically be possible to take a Raspberry Pi 2 to Debian armhf with a 32-bit kernel, but I haven t tried this and it may be more difficult. I have seen conflicting information on whether armhf really works on a Pi 2. (If you do try it on a Pi 2, ignore everything about arm64 and 64-bit kernels below, and just go with the linux-image-armmp-lpae kernel per the ARMMP page) There is another wrinkle: Debian doesn t support running 32-bit ARM kernels on 64-bit ARM CPUs, though it does support running a 32-bit userland on them. So we will wind up with a system with kernel packages from arm64 and everything else from armhf. This is a perfectly valid configuration as the arm64 like x86_64 is multiarch (that is, the CPU can natively execute both the 32-bit and 64-bit instructions). (It is theoretically possible to crossgrade a system from 32-bit to 64-bit userland, but that felt like a rather heavy lift for dubious benefit on a Pi; nevertheless, if you want to make this process even more complicated, refer to the CrossGrading page.)

Prerequisites and Limitations In addition to the need for a Raspberry Pi 3 or above in order for this to work, there are a few other things to mention. If you are using the GPIO features of the Pi, I don t know if those work with Debian. I think Raspberry Pi OS modified the desktop environment more than other components. All of my Pis are headless, so I don t know if this process will work if you use a desktop environment. I am assuming you are booting from a MicroSD card as is typical in the Raspberry Pi world. The Pi s firmware looks for a FAT partition (MBR type 0x0c) and looks within it for boot information. Depending on how long ago you first installed an OS on your Pi, your /boot may be too small for Debian. Use df -h /boot to see how big it is. I recommend 200MB at minimum. If your /boot is smaller than that, stop now (or use some other system to shrink your root filesystem and rearrange your partitions; I ve done this, but it s outside the scope of this article.) You need to have stable power. Once you begin this process, your pi will mostly be left in a non-bootable state until you finish. (You did make a backup, right?)

Basic idea The basic idea here is that since bookworm has almost entirely newer packages then bullseye, we can just switch over to it and let the Debian packages replace the Raspbian ones as they are upgraded. Well, it s not quite that easy, but that s the main idea.

Preparation First, make a backup. Even an image of your MicroSD card might be nice. OK, I think I ve said that enough now. It would be a good idea to have a HDMI cable (with the appropriate size of connector for your particular Pi board) and a HDMI display handy so you can troubleshoot any bootup issues with a console.

Preparation: access The Raspberry Pi OS by default sets up a user named pi that can use sudo to gain root without a password. I think this is an insecure practice, but assuming you haven t changed it, you will need to ensure it still works once you move to Debian. Raspberry Pi OS had a patch in their sudo package to enable it, and that will be removed when Debian s sudo package is installed. So, put this in /etc/sudoers.d/010_picompat:
pi ALL=(ALL) NOPASSWD: ALL
Also, there may be no password set for the root account. It would be a good idea to set one; it makes it easier to log in at the console. Use the passwd command as root to do so.

Preparation: bluetooth Debian doesn t correctly identify the Bluetooth hardware address. You can save it off to a file by running hcitool dev > /root/bluetooth-from-raspbian.txt. I don t use Bluetooth, but this should let you develop a script to bring it up properly.

Preparation: Debian archive keyring You will next need to install Debian s archive keyring so that apt can authenticate packages from Debian. Go to the bookworm download page for debian-archive-keyring and copy the URL for one of the files, then download it on the pi. For instance:
wget http://http.us.debian.org/debian/pool/main/d/debian-archive-keyring/debian-archive-keyring_2023.3+deb12u1_all.deb
Use sha256sum to verify the checksum of the downloaded file, comparing it to the package page on the Debian site. Now, you ll install it with:
dpkg -i debian-archive-keyring_2023.3+deb12u1_all.deb

Package first steps From here on, we are making modifications to the system that can leave it in a non-bootable state. Examine /etc/apt/sources.list and all the files in /etc/apt/sources.list.d. Most likely you will want to delete or comment out all lines in all files there. Replace them with something like:
deb http://deb.debian.org/debian/ bookworm main non-free-firmware contrib non-free
deb http://security.debian.org/debian-security bookworm-security main non-free-firmware contrib non-free
deb https://deb.debian.org/debian bookworm-backports main non-free-firmware contrib non-free
(you might leave off contrib and non-free depending on your needs) Now, we re going to tell it that we ll support arm64 packages:
dpkg --add-architecture arm64
And finally, download the bookworm package lists:
apt-get update
If there are any errors from that command, fix them and don t proceed until you have a clean run of apt-get update.

Moving /boot to /boot/firmware The boot FAT partition I mentioned above is mounted at /boot by Raspberry Pi OS, but Debian s scripts assume it will be at /boot/firmware. We need to fix this. First:
umount /boot
mkdir /boot/firmware
Now, edit fstab and change the reference to /boot to be to /boot/firmware. Now:
mount -v /boot/firmware
cd /boot/firmware
mv -vi * ..
This mounts the filesystem at the new location, and moves all its contents back to where apt believes it should be. Debian s packages will populate /boot/firmware later.

Installing the first packages Now we start by installing the first of the needed packages. Eventually we will wind up with roughly the same set Debian uses.
apt-get install linux-image-arm64
apt-get install firmware-brcm80211=20230210-5
apt-get install raspi-firmware
If you get errors relating to firmware-brcm80211 from any commands, run that install firmware-brcm80211 command and then proceed. There are a few packages that Raspbian marked as newer than the version in bookworm (whether or not they really are), and that s one of them.

Configuring the bootloader We need to configure a few things in /etc/default/raspi-firmware before proceeding. Edit that file. First, uncomment (or add) a line like this:
KERNEL_ARCH="arm64"
Next, in /boot/cmdline.txt you can find your old Raspbian boot command line. It will say something like:
root=PARTUUID=...
Save off the bit starting with PARTUUID. Back in /etc/default/raspi-firmware, set a line like this:
ROOTPART=PARTUUID=abcdef00
(substituting your real value for abcdef00). This is necessary because the microSD card device name often changes from /dev/mmcblk0 to /dev/mmcblk1 when switching to Debian s kernel. raspi-firmware will encode the current device name in /boot/firmware/cmdline.txt by default, which will be wrong once you boot into Debian s kernel. The PARTUUID approach lets it work regardless of the device name.

Purging the Raspbian kernel Run:
dpkg --purge raspberrypi-kernel

Upgrading the system At this point, we are going to run the procedure beginning at section 4.4.3 of the Debian release notes. Generally, you will do:
apt-get -u upgrade
apt full-upgrade
Fix any errors at each step before proceeding to the next. Now, to remove some cruft, run:
apt-get --purge autoremove
Inspect the list to make sure nothing important isn t going to be removed.

Removing Raspbian cruft You can list some of the cruft with:
apt list '~o'
And remove it with:
apt purge '~o'
I also don t run Bluetooth, and it seemed to sometimes hang on boot becuase I didn t bother to fix it, so I did:
apt-get --purge remove bluez

Installing some packages This makes sure some basic Debian infrastructure is available:
apt-get install wpasupplicant parted dosfstools wireless-tools iw alsa-tools
apt-get --purge autoremove

Installing firmware Now run:
apt-get install firmware-linux

Resolving firmware package version issues If it gives an error about the installed version of a package, you may need to force it to the bookworm version. For me, this often happened with firmware-atheros, firmware-libertas, and firmware-realtek. Here s how to resolve it, with firmware-realtek as an example:
  1. Go to https://packages.debian.org/PACKAGENAME for instance, https://packages.debian.org/firmware-realtek. Note the version number in bookworm in this case, 20230210-5.
  2. Now, you will force the installation of that package at that version:
    apt-get install firmware-realtek=20230210-5
    
  3. Repeat with every conflicting package until done.
  4. Rerun apt-get install firmware-linux and make sure it runs cleanly.
Also, in the end you should be able to:
apt-get install firmware-atheros firmware-libertas firmware-realtek firmware-linux

Dealing with other Raspbian packages The Debian release notes discuss removing non-Debian packages. There will still be a few of those. Run:
apt list '?narrow(?installed, ?not(?origin(Debian)))'
Deal with them; mostly you will need to force the installation of a bookworm version using the procedure in the section Resolving firmware package version issues above (even if it s not for a firmware package). For non-firmware packages, you might possibly want to add --mark-auto to your apt-get install command line to allow the package to be autoremoved later if the things depending on it go away. If you aren t going to use Bluetooth, I recommend apt-get --purge remove bluez as well. Sometimes it can hang at boot if you don t fix it up as described above.

Set up networking We ll be switching to the Debian method of networking, so we ll create some files in /etc/network/interfaces.d. First, eth0 should look like this:
allow-hotplug eth0
iface eth0 inet dhcp
iface eth0 inet6 auto
And wlan0 should look like this:
allow-hotplug wlan0
iface wlan0 inet dhcp
    wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
Raspbian is inconsistent about using eth0/wlan0 or renamed interface. Run ifconfig or ip addr. If you see a long-named interface such as enx<something> or wlp<something>, copy the eth0 file to the one named after the enx interface, or the wlan0 file to the one named after the wlp interface, and edit the internal references to eth0/wlan0 in this new file to name the long interface name. If using wifi, verify that your SSIDs and passwords are in /etc/wpa_supplicant/wpa_supplicant.conf. It should have lines like:
network= 
   ssid="NetworkName"
   psk="passwordHere"
 
(This is where Raspberry Pi OS put them).

Deal with DHCP Raspberry Pi OS used dhcpcd, whereas bookworm normally uses isc-dhcp-client. Verify the system is in the correct state:
apt-get install isc-dhcp-client
apt-get --purge remove dhcpcd dhcpcd-base dhcpcd5 dhcpcd-dbus

Set up LEDs To set up the LEDs to trigger on MicroSD activity as they did with Raspbian, follow the Debian instructions. Run apt-get install sysfsutils. Then put this in a file at /etc/sysfs.d/local-raspi-leds.conf:
class/leds/ACT/brightness = 1
class/leds/ACT/trigger = mmc1

Prepare for boot To make sure all the /boot/firmware files are updated, run update-initramfs -u. Verify that root in /boot/firmware/cmdline.txt references the PARTUUID as appropriate. Verify that /boot/firmware/config.txt contains the lines arm_64bit=1 and upstream_kernel=1. If not, go back to the section on modifying /etc/default/raspi-firmware and fix it up.

The moment arrives Cross your fingers and try rebooting into your Debian system:
reboot
For some reason, I found that the first boot into Debian seems to hang for 30-60 seconds during bootstrap. I m not sure why; don t panic if that happens. It may be necessary to power cycle the Pi for this boot.

Troubleshooting If things don t work out, hook up the Pi to a HDMI display and see what s up. If I anticipated a particular problem, I would have documented it here (a lot of the things I documented here are because I ran into them!) So I can t give specific advice other than to watch boot messages on the console. If you don t even get kernel messages going, then there is some problem with your partition table or /boot/firmware FAT partition. Otherwise, you ve at least got the kernel going and can troubleshoot like usual from there.

1 January 2024

Russ Allbery: 2023 Book Reading in Review

In 2023, I finished and reviewed 53 books, continuing a trend of year-over-year increases and of reading the most books since 2012 (the last year I averaged five books a month). Reviewing continued to be uneven, with a significant slump in the summer and smaller slumps in February and November, and a big clump of reviews finished in October in addition to my normal year-end reading and reviewing vacation. The unevenness this year was mostly due to finishing books and not writing reviews immediately. Reviews are much harder to write when the finished books are piling up, so one goal for 2024 is to not let that happen again. I enter the new year with one book finished and not yet reviewed, after reading a book about every day and a half during my December vacation. I read two all-time favorite books this year. The first was Emily Tesh's debut novel Some Desperate Glory, which is one of the best space opera novels I have ever read. I cannot improve on Shelley Parker-Chan's blurb for this book: "Fierce and heartbreakingly humane, this book is for everyone who loved Ender's Game, but Ender's Game didn't love them back." This is not hard science fiction but it is fantastic character fiction. It was exactly what I needed in the middle of a year in which I was fighting a "burn everything down" mood. The second was Night Watch by Terry Pratchett, the 29th Discworld and 6th Watch novel. Throughout my Discworld read-through, Pratchett felt like he was on the cusp of a truly stand-out novel, one where all the pieces fit and the book becomes something more than the sum of its parts. This was that book. It's a book about ethics and revolutions and governance, but also about how your perception of yourself changes as you get older. It does all of the normal Pratchett things, just... better. While I would love to point new Discworld readers at it, I think you do have to read at least the Watch novels that came before it for it to carry its proper emotional heft. This was overall a solid year for fiction reading. I read another 15 novels I rated 8 out of 10, and 12 that I rated 7 out of 10. The largest contributor to that was my Discworld read-through, which was reliably entertaining throughout the year. The run of Discworld books between The Fifth Elephant (read late last year) and Wintersmith (my last of this year) was the best run of Discworld novels so far. One additional book I'll call out as particularly worth reading is Thud!, the Watch novel after Night Watch and another excellent entry. I read two stand-out non-fiction books this year. The first was Oliver Darkshire's delightful memoir about life as a rare book seller, Once Upon a Tome. One of the things I will miss about Twitter is the regularity with which I stumbled across fascinating people and then got to read their books. I'm off Twitter permanently now because the platform is designed to make me incoherently angry and I need less of that in my life, but it was very good at finding delightfully quirky books like this one. My other favorite non-fiction book of the year was Michael Lewis's Going Infinite, a profile of Sam Bankman-Fried. I'm still bemused at the negative reviews that this got from people who were upset that Lewis didn't turn the story into a black-and-white morality play. Bankman-Fried's actions were clearly criminal; that's not in dispute. Human motivations can be complex in ways that are irrelevant to the law, and I thought this attempt to understand that complexity by a top-notch storyteller was worthy of attention. Also worth a mention is Tony Judt's Postwar, the first book I reviewed in 2023. A sprawling history of post-World-War-II Europe will never have the sheer readability of shorter, punchier books, but this was the most informative book that I read in 2023. 2024 should see the conclusion of my Discworld read-through, after which I may return to re-reading Mercedes Lackey or David Eddings, both of which I paused to make time for Terry Pratchett. I also have another re-read similar to my Chronicles of Narnia reviews that I've been thinking about for a while. Perhaps I will start that next year; perhaps it will wait for 2025. Apart from that, my intention as always is to read steadily, write reviews as close to when I finished the book as possible, and make reading time for my huge existing backlog despite the constant allure of new releases. Here's to a new year full of more new-to-me books and occasional old favorites. The full analysis includes some additional personal reading statistics, probably only of interest to me.

Tim Retout: Prevent DOM-XSS with Trusted Types - a smarter DevSecOps approach

It can be incredibly easy for a frontend developer to accidentally write a client-side cross-site-scripting (DOM-XSS) security issue, and yet these are hard for security teams to detect. Vulnerability scanners are slow, and suffer from false positives. Can smarter collaboration between development, operations and security teams provide a way to eliminate these problems altogether? Google claims that Trusted Types has all but eliminated DOM-XSS exploits on those of their sites which have implemented it. Let s find out how this can work!

DOM-XSS vulnerabilities are easy to write, but hard for security teams to catch It is very easy to accidentally introduce a client-side XSS problem. As an example of what not to do, suppose you are setting an element s text to the current URL, on the client side:
// Don't do this
para.innerHTML = location.href;
Unfortunately, an attacker can now manipulate the URL (and e.g. send this link in a phishing email), and any HTML tags they add will be interpreted by the user s browser. This could potentially be used by the attacker to send private data to a different server. Detecting DOM-XSS using vulnerability scanning tools is challenging - typically this requires crawling each page of the website and attempting to detect problems such as the one above, but there is a significant risk of false positives, especially as the complexity of the logic increases. There are already ways to avoid these exploits developers should validate untrusted input before making use of it. There are libraries such as DOMPurify which can help with sanitization.1 However, if you are part of a security team with responsibility for preventing these issues, it can be complex to understand whether you are at risk. Different developer teams may be using different techniques and tools. It may be impossible for you to work closely with every developer so how can you know that the frontend team have used these libraries correctly?

Trusted Types closes the DevSecOps feedback loop for DOM-XSS, by allowing Ops and Security to verify good Developer practices Trusted Types enforces sanitization in the browser2, by requiring the web developer to assign a particular kind of JavaScript object rather than a native string to .innerHTML and other dangerous properties. Provided these special types are created in an appropriate way, then they can be trusted not to expose XSS problems. This approach will work with whichever tools the frontend developers have chosen to use, and detection of issues can be rolled out by infrastructure engineers without requiring frontend code changes.

Content Security Policy allows enforcement of security policies in the browser itself Because enforcing this safer approach in the browser for all websites would break backwards-compatibility, each website must opt-in through Content Security Policy headers. Content Security Policy (CSP) is a mechanism that allows web pages to restrict what actions a browser should execute on their page, and a way for the site to receive reports if the policy is violated. Diagram showing a browser communicating with a web server. Content-Security-Policy headers are returned by the URL &ldquo;/&rdquo;, and the browser reports any security violations to &ldquo;/csp&rdquo;. Figure 1: Content-Security-Policy browser communication This is revolutionary, because it allows servers to receive feedback in real time on errors that may be appearing in the browser s console.

Trusted Types can be rolled out incrementally, with continuous feedback Web.dev s article on Trusted Types explains how to safely roll out the feature using the features of CSP itself:
  • Deploy a CSP collector if you haven t already
  • Switch on CSP reports without enforcement (via Content-Security-Policy-Report-Only headers)
  • Iteratively review and fix the violations
  • Switch to enforcing mode when there are a low enough rate of reports
Static analysis in a continuous integration pipeline is also sensible you want to prevent regressions shipping in new releases before they trigger a flood of CSP reports. This will also give you a chance of finding any low-traffic vulnerable pages.

Smart security teams will use techniques like Trusted Types to eliminate entire classes of bugs at a time Rather than playing whack-a-mole with unreliable vulnerability scanning or bug bounties, techniques such as Trusted Types are truly in the spirit of Secure by Design build high quality in from the start of the engineering process, and do this in a way which closes the DevSecOps feedback loop between your Developer, Operations and Security teams.

  1. Sanitization libraries are especially needed when the examples become more complex, e.g. if the application must manipulate the input. DOMPurify version 1.0.9 also added Trusted Types support, so can still be used to help developers adopt this feature.
  2. Trusted Types has existed in Chrome and Edge since 2020, and should soon be coming to Firefox as well. However, it s not necessary to wait for Firefox or Safari to add support, because the large market share of Chrome and Edge will let you identify and fix your site s DOM-XSS issues, even if you do not set enforcing mode, and users of all browsers will benefit. Even so, it is great that Mozilla is now on board.

31 December 2023

Chris Lamb: Favourites of 2023

This post should have marked the beginning of my yearly roundups of the favourite books and movies I read and watched in 2023. However, due to coming down with a nasty bout of flu recently and other sundry commitments, I wasn't able to undertake writing the necessary four or five blog posts In lieu of this, however, I will simply present my (unordered and unadorned) highlights for now. Do get in touch if this (or any of my previous posts) have spurred you into picking something up yourself

Books

Peter Watts: Blindsight (2006) Reymer Banham: Los Angeles: The Architecture of Four Ecologies (2006) Joanne McNeil: Lurking: How a Person Became a User (2020) J. L. Carr: A Month in the Country (1980) Hilary Mantel: A Memoir of My Former Self: A Life in Writing (2023) Adam Higginbotham: Midnight in Chernobyl (2019) Tony Judt: Postwar: A History of Europe Since 1945 (2005) Tony Judt: Reappraisals: Reflections on the Forgotten Twentieth Century (2008) Peter Apps: Show Me the Bodies: How We Let Grenfell Happen (2021) Joan Didion: Slouching Towards Bethlehem (1968)Erik Larson: The Devil in the White City (2003)

Films Recent releases

Unenjoyable experiences included Alejandro G mez Monteverde's Sound of Freedom (2023), Alex Garland's Men (2022) and Steven Spielberg's The Fabelmans (2022).
Older releases (Films released before 2022, and not including rewatches from previous years.) Distinctly unenjoyable watches included Ocean's Eleven (1960), El Topo (1970), L olo (1992), Hotel Mumbai (2018), Bulworth (1998) and and The Big Red One (1980).

30 December 2023

Riku Voipio: Adguard DNS, or how to reduce ads without apps/extensions

Looking at the options for blocking ads, people usually first look at browser extensions. Google's plan is to disable adblock extensions in 2024. The alternative is usually an app (on phones) or a "VPN" that does filtering for you. All these methods are quite heavyweight, and require installing software on your phone or PC. What is less known, is that you can you DNS-over-TLS or DNS-over-HTTPS for ad blocking.
What is DNS-over-TLS and DNS-over-HTTPS
Since Android 9, Google has provided a setting calledPrivate DNS. Traditional DNS is unencrypted UDP so anyone can monitor your requests and/or return false records. With private DNS, DNS-over-TLS or DNS-over-HTTPS is used to guarantee the DNS request is sent to the server you configured. Which Google hopes is of course Google's own public servers. If you do so, your ISP and hotspot providers no longer can monitor, monetize and enshittify your DNS requests - only Google can do so.
Subverting private DNS for ad blocking
This is where AdGuard DNS comes useful. By setting the AdGuard DNS server as your "private DNS" server following the instructions,you can start blocking right away. Note, on PC you can also configure the Adguard DNS server on the Browser settings (Firefox -> Enable secure DNS and Chrome -> Use Secure DNS) instead of configuring a system-wide DNS server. Blocking via DNS, of course, limits effectiveness to ads distributed from 3rd party servers.
Other uses for AdGuard DNS
If you register for Adguard DNS, you get your "own", customizable DNS server address to point to. You can, for example, create your own /etc/hosts style records that are now available to all you devices you have connected to the Adguard DNS server - whether your a are home or not. Of course, you choose to use the personal DNS server, your DNS query privacy is in the hands of AdGuard.
Going further
What else is ruining the web than Ads? Well commercial social media. An article ("Ei n in! Algoritmi hky") from the latest Finnish Magazine SKROLLI (mainos: jos luet suomeksi, Tilaa skrolli!) hit a chord for me. The algorithms of social media sites are designed not to serve you, but to addict you. For example, If you stop to watch a hateful meme image, the algorithm will record "The user spent time watching this, show more of the same!". It doesn't help block or mute - yeah that spefic hate engager will be blocked, but all the dozens similar hate pages will still be shown to you. Worse, the social media sites are being overrun by AI-generated crap. Unfortunately the addictive nature of the algorithms works. You reload in vain, hoping this time the algorithmic god will show something your friends share. How do you cure addiction? By blocking yourself out:
Epilogue
I didn't block myself out of Fediverse - yet. It's not engineered to be addictive, which is also probably why it isn't as popular as the commercial alternatives...

Russ Allbery: Review: The Hound of Justice

Review: The Hound of Justice, by Claire O'Dell
Series: Janet Watson Chronicles #2
Publisher: Harper Voyager
Copyright: July 2019
ISBN: 0-06-269938-5
Format: Kindle
Pages: 325
The Hound of Justice is a near-future thriller novel with Sherlock Holmes references. It is a direct sequel to A Study in Honor. This series is best read in order. Janet Watson is in a much better place than she was in the first book. She has proper physical therapy, a new arm, and a surgeon's job waiting for her as soon as she can master its features. A chance meeting due to an Inauguration Day terrorist attack may even develop into something more. She just needs to get back into the operating room and then she'll feel like her life is back on track. Sara Holmes, on the other hand, is restless, bored, and manic, rudely intruding on Watson's date. Then she disappears, upending Watson's living arrangements. She's on the trail of something. When mysterious destructible notes start appearing in Watson's books, it's clear that she wants help. The structure of this book didn't really work for me. The first third or so is a slice-of-life account of Watson's attempt to resume her career as a surgeon against a backdrop of ongoing depressing politics. This part sounds like the least interesting, but I was thoroughly engrossed. Watson is easy to care about, hospital politics are strangely interesting, and while the romance never quite clicked for me, it had potential. I was hoping for another book like A Study in Honor, where Watson's life and Holmes's investigations entwine and run in parallel. That was not to be. The middle third of the book pulls Watson away to Georgia and a complicated mix of family obligations and spy-novel machinations. If this had involved Sara's fae strangeness, verbal sparring, and odd tokens of appreciation, maybe it would have worked, but Sara Holmes is entirely off-camera. Watson is instead dealing with a minor supporting character from the first book, who drags her through disguises, vehicle changes, and border stops in a way that felt excessive and weirdly out of place. (Other reviews say that this character is the Mycroft Holmes equivalent; the first initial of Micha's name fits, but nothing else does so far as I can tell.) Then the last third of the novel turns into a heist. I like a heist novel as much as the next person, but a good heist story needs a team with chemistry and interplay, and I didn't know any of these people. There was way too little Sara Holmes, too much of Watson being out of her element in a rather generic way, and too many steps that Watson is led through without giving the reader a chance to enjoy the competence of the team. It felt jarring and disconnected, like Watson got pulled out of one story and dropped into an entirely different story without a proper groundwork. The Hound of Justice still has its moments. Watson is a great character and I'm still fully invested in her life. She was pulled into this mission because she's the person Holmes knows with the appropriate skills, and when she finally gets a chance to put those skills to use, it's quite satisfying. But, alas, the magic of A Study in Honor simply isn't here, in part because Sara Holmes is missing for most of the book and her replacements and stand-ins are nowhere near as intriguing. The villain's plan seems wildly impractical and highly likely to be detected, and although I can come up with some explanations to salvage it, those don't appear in the book. And, as in the first book, the villain seems very one-dimensional and simplistic. This is certainly not a villain worthy of Holmes. Fittingly, given the political movements O'Dell is commenting on, a lot of this book is about racial politics. O'Dell contrasts the microaggressions and more subtle dangers for Watson as a black woman in Washington, D.C., with the more explicit and active racism of the other places to which she travels over the course of the story. She's trying very hard to give the reader a feeling for what it's like to be black in the United States. I don't have any specific complaints about this, and I'm glad she's attempting it, but I came away from this book with a nagging feeling that Watson's reactions were a tiny bit off. It felt like a white person writing about racism rather than a black person writing about racism: nothing is entirely incorrect, but the emotional beats aren't quite where black authors would put them. I could be completely wrong about this, and am certainly much less qualified to comment than O'Dell is, but there were enough places that landed slightly wrong that I wanted to note it. I would still recommend A Study in Honor, but I'm not sure I can recommend this book. This is one of those series where the things that I enjoyed the most about the first book weren't what the author wanted to focus on in subsequent books. I would read more about the day-to-day of Watson's life, and I would certainly read more of Holmes and Watson sparring and circling and trying to understand each other. I'm less interested in somewhat generic thrillers with implausible plots and Sherlock Holmes references. At the moment, this is academic, since The Hound of Justice is the last book of the series so far. Rating: 6 out of 10

Valhalla's Things: I've been influenced

Posted on December 30, 2023
Tags: madeof:atoms
A woman wearing a red sleeveless dress; from the waist up it is fitted, while the skirt flares out. There is a white border with red embroidery and black fringe at the hem and a belt of the same material at the waist. By the influencers on the famous proprietary video platform1. When I m crafting with no powertools I tend to watch videos, and this autumn I ve seen a few in a row that were making red wool dresses, at least one or two medieval kirtles. I don t remember which channels they were, and I ve decided not to go back and look for them, at least for a time. A woman wearing a red shirt with wide sleeves, a short yoke, a small collar band and 3 buttons in the front. Anyway, my brain suddenly decided that I needed a red wool dress, fitted enough to give some bust support. I had already made a dress that satisfied the latter requirement and I still had more than half of the red wool faille I ve used for the Garibaldi blouse (still not blogged, but I will get to it), and this time I wanted it to be ready for this winter. While the pattern I was going to use is Victorian, it was designed for underwear, and this was designed to be outerwear, so from the very start I decided not to bother too much with any kind of historical details or techniques. A few meters of wool-imitation fringe trim rolled up; the fringe is black and is attached to a white band with a line of lozenge outlines in red and brown. I knew that I didn t have enough fabric to add a flounce to the hem, as in the cotton dress, but then I remembered that some time ago I fell for a piece of fringed trim in black, white and red. I did a quick check that the red wasn t clashing (it wasn t) and I knew I had a plan for the hem decoration. Then I spent a week finishing other projects, and the more I thought about this dress, the more I was tempted to have spiral lacing at the front rather than buttons, as a nod to the kirtle inspiration. It may end up be a bit of a hassle, but if it is too much I can always add a hidden zipper on a side seam, and only have to undo a bit of the lacing around the neckhole to wear the dress. Finally, I could start working on the dress: I cut all of the main pieces, and since the seam lines were quite curved I marked them with tailor s tacks, which I don t exactly enjoy doing or removing, but are the only method that was guaranteed to survive while manipulating this fabric (and not leave traces afterwards). A shaped piece of red fabric with the long edges bound in navy blue bias tape and all the seamlines marked with basting thread. While cutting the front pieces I accidentally cut the high neck line instead of the one I had used on the cotton dress: I decided to go for it also on the back pieces and decide later whether I wanted to lower it. Since this is a modern dress, with no historical accuracy at all, and I have access to a serger, I decided to use some dark blue cotton voile I ve had in my stash for quite some time, cut into bias strip, to bind the raw edges before sewing. This works significantly better than bought bias tape, which is a bit too stiff for this. A bigger piece of fabric with tailor's tacks for the seams and darts; at the top edge there is a strip of navy blue fabric sewn to a wide seaming allowance, with two rows of cording closest to the center front line. For the front opening, I ve decided to reinforce the areas where the lacing holes will be with cotton: I ve used some other navy blue cotton, also from the stash, and added two lines of cording to stiffen the front edge. So I ve cut the front in two pieces rather than on the fold, sewn the reinforcements to the sewing allowances in such a way that the corded edge was aligned with the center front and then sewn the bottom of the front seam from just before the end of the reinforcements to the hem. The front opening being worked on: on one side there are hand sewn eyelets in red silk that matches the fabric, on the other side the position for more eyelets are still marked with pins. There is also still basting to keep the folded allowance in place. The allowances are then folded back, and then they are kept in place by the worked lacing holes. The cotton was pinked, while for the wool I used the selvedge of the fabric and there was no need for any finishing. Behind the opening I ve added a modesty placket: I ve cut a strip of red wool, a strip of cotton, folded the edge of the strip of cotton to the center, added cording to the long sides, pressed the allowances of the wool towards the wrong side, and then handstitched the cotton to the wool, wrong sides facing. This was finally handstitched to one side of the sewing allowance of the center front. I ve also decided to add real pockets, rather than just slits, and for some reason I decided to add them by hand after I had sewn the dress, so I ve left opening in the side back seams, where the slits were in the cotton dress. I ve also already worn the dress, but haven t added the pockets yet, as I m still debating about their shape. This will be fixed in the near future. Another thing that will have to be fixed is the trim situation: I like the fringe at the bottom, and I had enough to also make a belt, but this makes the top of the dress a bit empty. I can t use the same fringe tape, as it is too wide, but it would be nice to have something smaller that matches the patterned part. And I think I can make something suitable with tablet weaving, but I m not sure on which materials to use, so it will have to be on hold for a while, until I decide on the supplies and have the time for making it. Another improvement I d like to add are detached sleeves, both matching (I should still have just enough fabric) and contrasting, but first I want to learn more about real kirtle construction, and maybe start making sleeves that would be suitable also for a real kirtle. Meanwhile, I ve worn it on Christmas (over my 1700s menswear shirt with big sleeves) and may wear it again tomorrow (if I bother to dress up to spend New Year s Eve at home :D )

  1. yep, that s YouTube, of course.

28 December 2023

Antonio Terceiro: Debian CI: 10 years later

It was 2013, and I was on a break from work between Christmas and New Year of 2013. I had been working at Linaro for well over a year, on the LAVA project. I was living and breathing automated testing infrastructure, mostly for testing low-level components such as kernels and bootloaders, on real hardware. At this point I was also a Debian contributor for quite some years, and had become an official project members two years prior. Most of my involvement was in the Ruby team, where we were already consistently running upstream test suites during package builds. During that break, I put these two contexts together, and came to the conclusion that Debian needed a dedicated service that would test the contents of the Debian archive. I was aware of the existance of autopkgtest, and started working on a very simple service that would later become Debian CI. In January 2014, debci was initially announced on that month's Misc Developer News, and later uploaded to Debian. It's been continuously developed for the last 10 years, evolved from a single shell script running tests in a loop into a distributed system with 47 geographically-distributed machines as of writing this piece, became part of the official Debian release process gating migrations to testing, had 5 Summer of Code and Outrechy interns working on it, and processed beyond 40 million test runs. In there years, Debian CI has received contributions from a lot of people, but I would like to give special credits to the following:

Next.

Previous.