• 2023-08-28, OSNews: The end of the Googleverse
• 2023-07-28, Cory Doctorow: Microincentives and Enshittification
• 2023-10-03, Cory Doctorow: Google s enshittification memos
• 2024-01-15, Tim Bray: Mourning Google

• More people are searching for alternatives to Google.
• Mainstream hard discs are incredibly big.
• Mainstream internet connection is incredibly fast.
• Google is bleeding talent.
• Most of the building blocks are available as free software.
• Success depends on your definition

A mildly technical computer user (able to install software) has access to a search engine that provides them with superior search results compared to Google for at least a few predefined areas of interest.

Back to the Future Time to admit something. I really love Plan 9. It s just so good. So many ideas from Plan 9 are just so prescient, and everything just feels right. Not just right like, feels good like, correct. The bit that I ve always liked the most is 9p, the network protocol for serving a filesystem over a network. This leads to all sorts of fun programs, like the Plan 9 ftp client being a 9p server you mount the ftp server and access files like any other files. It s kinda like if fuse were more fully a part of how the operating system worked, but fuse is all running client-side. With 9p there s a single client, and different servers that you can connect to, which may be backed by a hard drive, remote resources over something like SFTP, FTP, HTTP or even purely synthetic. The interesting (maybe sad?) part here is that 9p wound up outliving Plan 9 in terms of adoption 9p is in all sorts of places folks don t usually expect. For instance, the Windows Subsystem for Linux uses the 9p protocol to share files between Windows and Linux. ChromeOS uses it to share files with Crostini, and qemu uses 9p (virtio-p9) to share files between guest and host. If you re noticing a pattern here, you d be right; for some reason 9p is the go-to protocol to exchange files between hypervisor and guest. Why? I have no idea, except maybe due to being designed well, simple to implement, and it s a lot easier to validate the data being shared and validate security boundaries. Simplicity has its value. As a result, there s a lot of lingering 9p support kicking around. Turns out Linux can even handle mounting 9p filesystems out of the box. This means that I can deploy a filesystem to my LAN or my localhost by running a process on top of a computer that needs nothing special, and mount it over the network on an unmodified machine unlike fuse, where you d need client-specific software to run in order to mount the directory. For instance, let s mount a 9p filesystem running on my localhost machine, serving requests on 127.0.0.1:564 (tcp) that goes by the name mountpointname to /mnt.

$ mount -t 9p \
-o trans=tcp,port=564,version=9p2000.u,aname=mountpointname \
127.0.0.1 \
/mnt

Linux will mount away, and attach to the filesystem as the root user, and by default, attach to that mountpoint again for each local user that attempts to use it. Nifty, right? I think so. The server is able to keep track of per-user access and authorization along with the host OS.

WHEREIN I STYX WITH IT Since I wanted to push myself a bit more with rust and tokio specifically, I opted to implement the whole stack myself, without third party libraries on the critical path where I could avoid it. The 9p protocol (sometimes called Styx, the original name for it) is incredibly simple. It s a series of client to server requests, which receive a server to client response. These are, respectively, T messages, which transmit a request to the server, which trigger an R message in response (Reply messages). These messages are TLV payload with a very straight forward structure so straight forward, in fact, that I was able to implement a working server off nothing more than a handful of man pages. Later on after the basics worked, I found a more complete spec page that contains more information about the unix specific variant that I opted to use (9P2000.u rather than 9P2000) due to the level of Linux specific support for the 9P2000.u variant over the 9P2000 protocol.

MR ROBOTO The backend stack over at zoo is rust and tokio running i/o for an HTTP and WebRTC server. I figured I d pick something fairly similar to write my filesystem with, since 9P can be implemented on basically anything with I/O. That means tokio tcp server bits, which construct and use a 9p server, which has an idiomatic Rusty API that partially abstracts the raw R and T messages, but not so much as to cause issues with hiding implementation possibilities. At each abstraction level, there s an escape hatch allowing someone to implement any of the layers if required. I called this framework arigato which can be found over on docs.rs and crates.io.

/// Simplified version of the arigato File trait; this isn't actually
/// the same trait; there's some small cosmetic differences. The
/// actual trait can be found at:
///
/// https://docs.rs/arigato/latest/arigato/server/trait.File.html
trait File  
/// OpenFile is the type returned by this File via an Open call.
 type OpenFile: OpenFile;
/// Return the 9p Qid for this file. A file is the same if the Qid is
 /// the same. A Qid contains information about the mode of the file,
 /// version of the file, and a unique 64 bit identifier.
 fn qid(&self) -> Qid;
/// Construct the 9p Stat struct with metadata about a file.
 async fn stat(&self) -> FileResult<Stat>;
/// Attempt to update the file metadata.
 async fn wstat(&mut self, s: &Stat) -> FileResult<()>;
/// Traverse the filesystem tree.
 async fn walk(&self, path: &[&str]) -> FileResult<(Option<Self>, Vec<Self>)>;
/// Request that a file's reference be removed from the file tree.
 async fn unlink(&mut self) -> FileResult<()>;
/// Create a file at a specific location in the file tree.
 async fn create(
&mut self,
name: &str,
perm: u16,
ty: FileType,
mode: OpenMode,
extension: &str,
) -> FileResult<Self>;
/// Open the File, returning a handle to the open file, which handles
 /// file i/o. This is split into a second type since it is genuinely
 /// unrelated -- and the fact that a file is Open or Closed can be
 /// handled by the  arigato  server for us.
 async fn open(&mut self, mode: OpenMode) -> FileResult<Self::OpenFile>;
 
/// Simplified version of the arigato OpenFile trait; this isn't actually
/// the same trait; there's some small cosmetic differences. The
/// actual trait can be found at:
///
/// https://docs.rs/arigato/latest/arigato/server/trait.OpenFile.html
trait OpenFile  
/// iounit to report for this file. The iounit reported is used for Read
 /// or Write operations to signal, if non-zero, the maximum size that is
 /// guaranteed to be transferred atomically.
 fn iounit(&self) -> u32;
/// Read some number of bytes up to  buf.len()  from the provided
 ///  offset  of the underlying file. The number of bytes read is
 /// returned.
 async fn read_at(
&mut self,
buf: &mut [u8],
offset: u64,
) -> FileResult<u32>;
/// Write some number of bytes up to  buf.len()  from the provided
 ///  offset  of the underlying file. The number of bytes written
 /// is returned.
 fn write_at(
&mut self,
buf: &mut [u8],
offset: u64,
) -> FileResult<u32>;
 

Thanks, decade ago paultag! Let s do it! Let s use arigato to implement a 9p filesystem we ll call debugfs that will serve all the debug files shipped according to the Packages metadata from the apt archive. We ll fetch the Packages file and construct a filesystem based on the reported Build-Id entries. For those who don t know much about how an apt repo works, here s the 2-second crash course on what we re doing. The first is to fetch the Packages file, which is specific to a binary architecture (such as amd64, arm64 or riscv64). That architecture is specific to a component (such as main, contrib or non-free). That component is specific to a suite, such as stable, unstable or any of its aliases (bullseye, bookworm, etc). Let s take a look at the Packages.xz file for the unstable-debug suite, main component, for all amd64 binaries.

$ curl \
https://deb.debian.org/debian-debug/dists/unstable-debug/main/binary-amd64/Packages.xz \
  unxz

This will return the Debian-style rfc2822-like headers, which is an export of the metadata contained inside each .deb file which apt (or other tools that can use the apt repo format) use to fetch information about debs. Let s take a look at the debug headers for the netlabel-tools package in unstable which is a package named netlabel-tools-dbgsym in unstable-debug.

Package: netlabel-tools-dbgsym
Source: netlabel-tools (0.30.0-1)
Version: 0.30.0-1+b1
Installed-Size: 79
Maintainer: Paul Tagliamonte <paultag@debian.org>
Architecture: amd64
Depends: netlabel-tools (= 0.30.0-1+b1)
Description: debug symbols for netlabel-tools
Auto-Built-Package: debug-symbols
Build-Ids: e59f81f6573dadd5d95a6e4474d9388ab2777e2a
Description-md5: a0e587a0cf730c88a4010f78562e6db7
Section: debug
Priority: optional
Filename: pool/main/n/netlabel-tools/netlabel-tools-dbgsym_0.30.0-1+b1_amd64.deb
Size: 62776
SHA256: 0e9bdb087617f0350995a84fb9aa84541bc4df45c6cd717f2157aa83711d0c60

So here, we can parse the package headers in the Packages.xz file, and store, for each Build-Id, the Filename where we can fetch the .deb at. Each .deb contains a number of files but we re only really interested in the files inside the .deb located at or under /usr/lib/debug/.build-id/, which you can find in debugfs under rfc822.rs. It s crude, and very single-purpose, but I m feeling a bit lazy.

Who needs dpkg?! For folks who haven t seen it yet, a .deb file is a special type of .ar file, that contains (usually) three files inside debian-binary, control.tar.xz and data.tar.xz. The core of an .ar file is a fixed size (60 byte) entry header, followed by the specified size number of bytes.

[8 byte .ar file magic]
[60 byte entry header]
[N bytes of data]
[60 byte entry header]
[N bytes of data]
[60 byte entry header]
[N bytes of data]
...

First up was to implement a basic ar parser in ar.rs. Before we get into using it to parse a deb, as a quick diversion, let s break apart a .deb file by hand something that is a bit of a rite of passage (or at least it used to be? I m getting old) during the Debian nm (new member) process, to take a look at where exactly the .debug file lives inside the .deb file.

$ ar x netlabel-tools-dbgsym_0.30.0-1+b1_amd64.deb
$ ls
control.tar.xz debian-binary
data.tar.xz netlabel-tools-dbgsym_0.30.0-1+b1_amd64.deb
$ tar --list -f data.tar.xz   grep '.debug$'
./usr/lib/debug/.build-id/e5/9f81f6573dadd5d95a6e4474d9388ab2777e2a.debug

Since we know quite a bit about the structure of a .deb file, and I had to implement support from scratch anyway, I opted to implement a (very!) basic debfile parser using HTTP Range requests. HTTP Range requests, if supported by the server (denoted by a accept-ranges: bytes HTTP header in response to an HTTP HEAD request to that file) means that we can add a header such as range: bytes=8-68 to specifically request that the returned GET body be the byte range provided (in the above case, the bytes starting from byte offset 8 until byte offset 68). This means we can fetch just the ar file entry from the .deb file until we get to the file inside the .deb we are interested in (in our case, the data.tar.xz file) at which point we can request the body of that file with a final range request. I wound up writing a struct to handle a read_at-style API surface in hrange.rs, which we can pair with ar.rs above and start to find our data in the .deb remotely without downloading and unpacking the .deb at all. After we have the body of the data.tar.xz coming back through the HTTP response, we get to pipe it through an xz decompressor (this kinda sucked in Rust, since a tokio AsyncRead is not the same as an http Body response is not the same as std::io::Read, is not the same as an async (or sync) Iterator is not the same as what the xz2 crate expects; leading me to read blocks of data to a buffer and stuff them through the decoder by looping over the buffer for each lzma2 packet in a loop), and tarfile parser (similarly troublesome). From there we get to iterate over all entries in the tarfile, stopping when we reach our file of interest. Since we can t seek, but gdb needs to, we ll pull it out of the stream into a Cursor<Vec<u8>> in-memory and pass a handle to it back to the user. From here on out its a matter of gluing together a File traited struct in debugfs, and serving the filesystem over TCP using arigato. Done deal!

A quick diversion about compression I was originally hoping to avoid transferring the whole tar file over the network (and therefore also reading the whole debug file into ram, which objectively sucks), but quickly hit issues with figuring out a way around seeking around an xz file. What s interesting is xz has a great primitive to solve this specific problem (specifically, use a block size that allows you to seek to the block as close to your desired seek position just before it, only discarding at most block size - 1 bytes), but data.tar.xz files generated by dpkg appear to have a single mega-huge block for the whole file. I don t know why I would have expected any different, in retrospect. That means that this now devolves into the base case of How do I seek around an lzma2 compressed data stream ; which is a lot more complex of a question. Thankfully, notoriously brilliant tianon was nice enough to introduce me to Jon Johnson who did something super similar adapted a technique to seek inside a compressed gzip file, which lets his service oci.dag.dev seek through Docker container images super fast based on some prior work such as soci-snapshotter, gztool, and zran.c. He also pulled this party trick off for apk based distros over at apk.dag.dev, which seems apropos. Jon was nice enough to publish a lot of his work on this specifically in a central place under the name targz on his GitHub, which has been a ton of fun to read through. The gist is that, by dumping the decompressor s state (window of previous bytes, in-memory data derived from the last N-1 bytes) at specific checkpoints along with the compressed data stream offset in bytes and decompressed offset in bytes, one can seek to that checkpoint in the compressed stream and pick up where you left off creating a similar block mechanism against the wishes of gzip. It means you d need to do an O(n) run over the file, but every request after that will be sped up according to the number of checkpoints you ve taken. Given the complexity of xz and lzma2, I don t think this is possible for me at the moment especially given most of the files I ll be requesting will not be loaded from again especially when I can just cache the debug header by Build-Id. I want to implement this (because I m generally curious and Jon has a way of getting someone excited about compression schemes, which is not a sentence I thought I d ever say out loud), but for now I m going to move on without this optimization. Such a shame, since it kills a lot of the work that went into seeking around the .deb file in the first place, given the debian-binary and control.tar.gz members are so small.

The Good First, the good news right? It works! That s pretty cool. I m positive my younger self would be amused and happy to see this working; as is current day paultag. Let s take debugfs out for a spin! First, we need to mount the filesystem. It even works on an entirely unmodified, stock Debian box on my LAN, which is huge. Let s take it for a spin:

$ mount \
-t 9p \
-o trans=tcp,version=9p2000.u,aname=unstable-debug \
192.168.0.2 \
/usr/lib/debug/.build-id/

And, let s prove to ourselves that this actually mounted before we go trying to use it:

$ mount   grep build-id
192.168.0.2 on /usr/lib/debug/.build-id type 9p (rw,relatime,aname=unstable-debug,access=user,trans=tcp,version=9p2000.u,port=564)

Slick. We ve got an open connection to the server, where our host will keep a connection alive as root, attached to the filesystem provided in aname. Let s take a look at it.

$ ls /usr/lib/debug/.build-id/
00 0d 1a 27 34 41 4e 5b 68 75 82 8E 9b a8 b5 c2 CE db e7 f3
01 0e 1b 28 35 42 4f 5c 69 76 83 8f 9c a9 b6 c3 cf dc E7 f4
02 0f 1c 29 36 43 50 5d 6a 77 84 90 9d aa b7 c4 d0 dd e8 f5
03 10 1d 2a 37 44 51 5e 6b 78 85 91 9e ab b8 c5 d1 de e9 f6
04 11 1e 2b 38 45 52 5f 6c 79 86 92 9f ac b9 c6 d2 df ea f7
05 12 1f 2c 39 46 53 60 6d 7a 87 93 a0 ad ba c7 d3 e0 eb f8
06 13 20 2d 3a 47 54 61 6e 7b 88 94 a1 ae bb c8 d4 e1 ec f9
07 14 21 2e 3b 48 55 62 6f 7c 89 95 a2 af bc c9 d5 e2 ed fa
08 15 22 2f 3c 49 56 63 70 7d 8a 96 a3 b0 bd ca d6 e3 ee fb
09 16 23 30 3d 4a 57 64 71 7e 8b 97 a4 b1 be cb d7 e4 ef fc
0a 17 24 31 3e 4b 58 65 72 7f 8c 98 a5 b2 bf cc d8 E4 f0 fd
0b 18 25 32 3f 4c 59 66 73 80 8d 99 a6 b3 c0 cd d9 e5 f1 fe
0c 19 26 33 40 4d 5a 67 74 81 8e 9a a7 b4 c1 ce da e6 f2 ff

Outstanding. Let s try using gdb to debug a binary that was provided by the Debian archive, and see if it ll load the ELF by build-id from the right .deb in the unstable-debug suite:

$ gdb -q /usr/sbin/netlabelctl
Reading symbols from /usr/sbin/netlabelctl...
Reading symbols from /usr/lib/debug/.build-id/e5/9f81f6573dadd5d95a6e4474d9388ab2777e2a.debug...
(gdb)

Yes! Yes it will!

$ file /usr/lib/debug/.build-id/e5/9f81f6573dadd5d95a6e4474d9388ab2777e2a.debug
/usr/lib/debug/.build-id/e5/9f81f6573dadd5d95a6e4474d9388ab2777e2a.debug: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter *empty*, BuildID[sha1]=e59f81f6573dadd5d95a6e4474d9388ab2777e2a, for GNU/Linux 3.2.0, with debug_info, not stripped

The Bad Linux s support for 9p is mainline, which is great, but it s not robust. Network issues or server restarts will wedge the mountpoint (Linux can t reconnect when the tcp connection breaks), and things that work fine on local filesystems get translated in a way that causes a lot of network chatter for instance, just due to the way the syscalls are translated, doing an ls, will result in a stat call for each file in the directory, even though linux had just got a stat entry for every file while it was resolving directory names. On top of that, Linux will serialize all I/O with the server, so there s no concurrent requests for file information, writes, or reads pending at the same time to the server; and read and write throughput will degrade as latency increases due to increasing round-trip time, even though there are offsets included in the read and write calls. It works well enough, but is frustrating to run up against, since there s not a lot you can do server-side to help with this beyond implementing the 9P2000.L variant (which, maybe is worth it).

The Ugly Unfortunately, we don t know the file size(s) until we ve actually opened the underlying tar file and found the correct member, so for most files, we don t know the real size to report when getting a stat. We can t parse the tarfiles for every stat call, since that d make ls even slower (bummer). Only hiccup is that when I report a filesize of zero, gdb throws a bit of a fit; let s try with a size of 0 to start:

$ ls -lah /usr/lib/debug/.build-id/e5/9f81f6573dadd5d95a6e4474d9388ab2777e2a.debug
-r--r--r-- 1 root root 0 Dec 31 1969 /usr/lib/debug/.build-id/e5/9f81f6573dadd5d95a6e4474d9388ab2777e2a.debug
$ gdb -q /usr/sbin/netlabelctl
Reading symbols from /usr/sbin/netlabelctl...
Reading symbols from /usr/lib/debug/.build-id/e5/9f81f6573dadd5d95a6e4474d9388ab2777e2a.debug...
warning: Discarding section .note.gnu.build-id which has a section size (24) larger than the file size [in module /usr/lib/debug/.build-id/e5/9f81f6573dadd5d95a6e4474d9388ab2777e2a.debug]
[...]

This obviously won t work since gdb will throw away all our hard work because of stat s output, and neither will loading the real size of the underlying file. That only leaves us with hardcoding a file size and hope nothing else breaks significantly as a result. Let s try it again:

$ ls -lah /usr/lib/debug/.build-id/e5/9f81f6573dadd5d95a6e4474d9388ab2777e2a.debug
-r--r--r-- 1 root root 954M Dec 31 1969 /usr/lib/debug/.build-id/e5/9f81f6573dadd5d95a6e4474d9388ab2777e2a.debug
$ gdb -q /usr/sbin/netlabelctl
Reading symbols from /usr/sbin/netlabelctl...
Reading symbols from /usr/lib/debug/.build-id/e5/9f81f6573dadd5d95a6e4474d9388ab2777e2a.debug...
(gdb)

Much better. I mean, terrible but better. Better for now, anyway.

Kilroy was here Do I think this is a particularly good idea? I mean; kinda. I m probably going to make some fun 9p arigato-based filesystems for use around my LAN, but I don t think I ll be moving to use debugfs until I can figure out how to ensure the connection is more resilient to changing networks, server restarts and fixes on i/o performance. I think it was a useful exercise and is a pretty great hack, but I don t think this ll be shipping anywhere anytime soon. Along with me publishing this post, I ve pushed up all my repos; so you should be able to play along at home! There s a lot more work to be done on arigato; but it does handshake and successfully export a working 9P2000.u filesystem. Check it out on on my github at arigato, debugfs and also on crates.io and docs.rs. At least I can say I was here and I got it working after all these years.

1. I don't have the tools to open my old laptop and connect the new disk over USB to my new laptop.
2. I use full disk encryption, and my old laptop has a 512GB disk, whereas the new laptop has a 1TB NVME, and I'm not so familiar with resizing LUKS.

1. Export the disk using nvmet-tcp from the old laptop.
2. Do a disk copy to the new laptop.
3. Resize the partition to use the full 1TB.
4. Resize LUKS.
5. Finally, resize the BTRFS root disk.

modprobe nvmet-tcp
cd /sys/kernel/config/nvmet
mkdir ports/0
cd ports/0
echo "ipv4" > addr_adrfam
echo 0.0.0.0 > addr_traaddr
echo 4420 > addr_trsvcid
echo tcp > addr_trtype
cd /sys/kernel/config/nvmet/subsystems
mkdir testnqn
echo 1 >testnqn/allow_any_host
mkdir testnqn/namespaces/1
cd testnqn
# replace the device name with the disk you want to export
echo "/dev/nvme0n1" > namespaces/1/device_path
echo 1 > namespaces/1/enable
ln -s "../../subsystems/testnqn" /sys/kernel/config/nvmet/ports/0/subsystems/testnqn

nvme discover -t tcp -a <ip> -s 4420
nvme connectl-all -t tcp -a <> -s 4420

dd if=/dev/nvme2n1 of=/dev/nvme0n1 status=progress bs=40M

growpart /dev/nvem0n1 p2

cryptsetup luksOpen /dev/nvme0n1p2 ENC
cryptsetup resize ENC

btfs fielsystem resize max /

• Uses blockdev-backup QMP commands instead of the soon to be deprecated drive-backup.
• Adds --compress option: target QCOW files data can be compressed.
• Adds --speed-limit option to limit backup speed throughput.
• Adds --include-raw option so attached raw devices can be backed up too.
• Allows backing up virtual machines in paused or pre-running state.
• Adds backup option copy to allow backing up virtual machines with older qcow image formats, that are not supporting persistent bitmaps.
• Improved logging output.

auto end0
iface end0 inet dhcp

rm /etc/ssh/ssh_host_*
systemctl restart ssh.service

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

• [1] https://sipeed.com/licheepi4a
• [2] https://wiki.sipeed.com/hardware/en/lichee/th1520/lp4a.html
• [3] https://www.ssh-audit.com/

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...

Conferences The only Free Software related conference I made it to this year was DebConf23 in Kochi, India. Changes with projects at work meant I couldn t justify anything work related. This year I m planning to make it to FOSDEM, and haven t made a decision on DebConf24 yet.

Debian Most of my contributions to Free software continue to happen within Debian. I started the year working on retrogaming with Kodi on Debian. I got this to a much better state for bookworm, with it being possible to run the bsnes-mercury emulator under Kodi using RetroArch. There are a few other libretro backends available for RetroArch, but Kodi needs some extra controller mappings packaged up first. Plenty of uploads were involved, though some of this was aligning all the dependencies and generally cleaning things up in iterations.

• retroarch: 1.13.0-dfsg+3, 1.14.0+dfsg-1, 1.15.0+dfsg-1, 1.16.0.3+dfgs-1
• libretro-core-info uploads: 1.14.0-1, 1.15.0-1.
• libretro-bsnes-mercury: 094+git20220807-2, 094+git20220807-3, 094+git20220807-4, 094+git20220807-5, 094+git20220807-6, 094+git20220807-7, 094+git20220807-8.
• kodi-game-libretro: 20.2.0-2, 20.2.2-1, 20.2.2-2, 20.2.4-1, 20.2.4-2
• rcheevos: 10.5.0-2, 10.6.0-1, 10.7.0-1, 10.7.1-1.

I continued to work on a few packages within the Debian Electronics Packaging Team. OpenOCD produced a new release in time for the bookworm release, so I uploaded 0.12.0-1. There were a few minor sigrok cleanups - sigrok 0.3, libsigrokdecode 0.5.3-4 + libsigrok 0.5.2-4 / 0.5.2-5. While I didn t manage to get the work completed I did some renaming of the ESP8266 related packages - gcc-xtensa-lx106 (which saw a 13 upload pre-bookworm) has become gcc-xtensa (with 14) and binutils-xtensa-lx106 has become binutils-xtensa (with 6). Binary packages remain the same, but this is intended to allow for the generation of ESP32 compiler toolchains from the same source. onak saw 0.6.3-1 uploaded to match the upstream release. I also uploaded libgpg-error 1.47-1 (though I can claim no credit for any of the work in preparing the package) to help move things forward on updating gnupg2 in Debian. I NMUed tpm2-pkcs11 1.9.0-0.1 to fix some minor issues pre-bookworm release; I use this package myself to store my SSH key within my laptop TPM, so I care about it being in a decent state. sg3-utils also saw a bit of love with 1.46-2 + 1.46-3 - I don t work in the storage space these days, but I m still listed as an uploaded and there was an RC bug around the library package naming that I was qualified to fix and test pre-bookworm. Related to my retroarch work I sponsored uploads of mgba for Ryan Tandy: 0.10.0+dfsg-1, 0.10.0+dfsg-2, 0.10.1+dfsg-1, 0.10.2+dfsg-1, mgba 0.10.1+dfsg-1+deb12u1. As part of the Data Protection Team I responded to various inbound queries to that team, both from project members and those external to the project. I continue to keep an eye on Debian New Members, even though I m mostly inactive as an application manager - we generally seem to have enough available recently. Mostly my involvement is via Front Desk activities, helping out with queries to the team alias, and contributing to internal discussions as well as our panel at DebConf23. Finally the 3 month rotation for Debian Keyring continues to operate smoothly. I dealt with 2023.03.24, 2023.06.26, 2023.06.29, 2023.09.10, 2023.09.24 + 2023.12.24.

Linux I had a few minor patches accepted to the kernel this year. A pair of safexcel cleanups (improved error logging for firmware load fail and cleanup on load failure) came out of upgrading the kernel running on my RB5009. The rest were related to my work on repurposing my C.H.I.P.. The AXP209 driver needed extended to support GPIO3 (with associated DT schema update). That allowed Bluetooth to be enabled. Adding the AXP209 internal temperature ADC as an iio-hwmon node means it can be tracked using the normal sensor monitoring framework. And finally I added the pinmux settings for mmc2, which I use to support an external microSD slot on my C.H.I.P.

Personal projects 2023 saw another minor release of onak, 0.6.3, which resulted in a corresponding Debian upload (0.6.3-1). It has a couple of bug fixes (including a particularly annoying, if minor, one around systemd socket activation that felt very satisfying to get to the bottom of), but I still lack the time to do any of the major changes I would like to. I wrote listadmin3 to allow easy manipulation of moderation queues for Mailman3. It s basic, but it s drastically improved my timeliness on dealing with held messages.

Work related This year only involved a single upstream related submission; a fix for tpm_tis interrupts with the Lenovo P620 that then got dropped when the change that caused the issue was reverted. That wraps up 2023. I ve got no particular goals for this year; looking around my desk I ve a few ARM based devices I d like to get running a mainline kernel. I need to play about a bit more with the retroarch bits (if I really had time I d do the migration for Kodi to PCRE2, as that s currently causing testing migration issues), perhaps getting some more controller mappings packaged. But no promises.

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

• The Blue Caftan (Maryam Touzani, 2022)
• The Eight Mountains (Felix van Groeningen & Charlotte Vandermeersch, 2022)
• Evil Does Not Exist (Ryusuke Hamaguchi, 2023)
• Killers of the Flower Moon (Martin Scorcese, 2023)
• Monster (Hirokazu Kore-eda, 2023)
• Passages (Ira Sachs, 2023)
• Poor Things (Yorgos Lanthimos, 2023)
• The Tuba Thieves (Alison O Daniel, 2023)
• Theater Camp (Molly Gordon and Nick Lieberman, 2023)
• T R (Todd Field, 2022)

• Brief Encounter (David Lean, 1945)
• Clouds of Sils Maria (Olivier Assayas, 2014)
• Daisy Miller (Peter Bogdanovich, 1974)
• First Reformed (Paul Schrader, 2017)
• Forbidden Games (Ren Cl ment, 1952)
• La Noire de... (Ousmane Semb ne, 1966)
• The Queen of Spades (Thorold Dickinson, 1949)
• The River (Jean Renoir, 1951)
• Topsy-Turvy (Mike Leigh, 1999)
• Le Trou (Jacques Becker, 1960)

Pre-Debugging Steps: Before diving into an issue, it s crucial to perform two essential steps: 1) Check the latest changes: Ensure you re working with the latest AMD driver modifications located in the amd-staging-drm-next branch maintained by Alex Deucher. You may also find bug fixes for newer kernel versions on branches that have the name pattern drm-fixes-<date>. 2) Examine the issue tracker: Confirm that your issue isn t already documented and addressed in the AMD display driver issue tracker. If you find a similar issue, you can team up with others and speed up the debugging process.

Understanding the issue: Do you really need to change this? Where should you start looking for changes? 3) Is the issue in the AMD kernel driver or in the userspace?: Identifying the source of the issue is essential regardless of the GPU vendor. Sometimes this can be challenging so here are some helpful tips:

• Record the screen: Capture the screen using a recording app while experiencing the issue. If the bug appears in the capture, it s likely a userspace issue, not the kernel display driver.
• Analyze the dmesg log: Look for error messages related to the display driver in the dmesg log. If the error message appears before the message [drm] Display Core v... , it s not likely a display driver issue. If this message doesn t appear in your log, the display driver wasn t fully loaded and you will see a notification that something went wrong here.

4) AMD Display Manager vs. AMD Display Core: The AMD display driver consists of two components:

• Display Manager (DM): This component interacts directly with the Linux DRM infrastructure. Occasionally, issues can arise from misinterpretations of DRM properties or features. If the issue doesn t occur on other platforms with the same AMD hardware - for example, only happens on Linux but not on Windows - it s more likely related to the AMD DM code.
• Display Core (DC): This is the platform-agnostic part responsible for setting and programming hardware features. Modifications to the DC usually require validation on other platforms, like Windows, to avoid regressions.

5) Identify the DC HW family: Each AMD GPU has variations in its hardware architecture. Features and helpers differ between families, so determining the relevant code for your specific hardware is crucial.

• Find GPU product information in Linux/AMD GPU documentation
• Check the dmesg log for the Display Core version (since this commit in Linux kernel 6.3v). For example:
  • [drm] Display Core v3.2.241 initialized on DCN 2.1
  • [drm] Display Core v3.2.237 initialized on DCN 3.0.1

Investigating the relevant driver code: Keep from letting unrelated driver code to affect your investigation. 6) Narrow the code inspection down to one DC HW family: the relevant code resides in a directory named after the DC number. For example, the DCN 3.0.1 driver code is located at drivers/gpu/drm/amd/display/dc/dcn301. We all know that the AMD s shared code is huge and you can use these boundaries to rule out codes unrelated to your issue. 7) Newer families may inherit code from older ones: you can find dcn301 using code from dcn30, dcn20, dcn10 files. It s crucial to verify which hooks and helpers your driver utilizes to investigate the right portion. You can leverage ftrace for supplemental validation. To give an example, it was useful when I was updating DCN3 color mapping to correctly use their new post-blending color capabilities, such as:

• [PATCH] drm/amd/display: set stream gamut remap matrix to MPC for DCN3+

Additionally, you can use two different HW families to compare behaviours. If you see the issue in one but not in the other, you can compare the code and understand what has changed and if the implementation from a previous family doesn t fit well the new HW resources or design. You can also count on the help of the community on the Linux AMD issue tracker to validate your code on other hardware and/or systems. This approach helped me debug a 2-year-old issue where the cursor gamma adjustment was incorrect in DCN3 hardware, but working correctly for DCN2 family. I solved the issue in two steps, thanks for community feedback and validation:

• [PATCH] drm/amd/display: check attr flag before set cursor degamma on DCN3+
• [PATCH] drm/amd/display: enable cursor degamma for DCN3+ DRM legacy gamma

8) Check the hardware capability screening in the driver: You can currently find a list of display hardware capabilities in the drivers/gpu/drm/amd/display/dc/dcn*/dcn*_resource.c file. More precisely in the dcn*_resource_construct() function. Using DCN301 for illustration, here is the list of its hardware caps:

	/*************************************************
	 *  Resource + asic cap harcoding                *
	 *************************************************/
	pool->base.underlay_pipe_index = NO_UNDERLAY_PIPE;
	pool->base.pipe_count = pool->base.res_cap->num_timing_generator;
	pool->base.mpcc_count = pool->base.res_cap->num_timing_generator;
	dc->caps.max_downscale_ratio = 600;
	dc->caps.i2c_speed_in_khz = 100;
	dc->caps.i2c_speed_in_khz_hdcp = 5; /*1.4 w/a enabled by default*/
	dc->caps.max_cursor_size = 256;
	dc->caps.min_horizontal_blanking_period = 80;
	dc->caps.dmdata_alloc_size = 2048;
	dc->caps.max_slave_planes = 2;
	dc->caps.max_slave_yuv_planes = 2;
	dc->caps.max_slave_rgb_planes = 2;
	dc->caps.is_apu = true;
	dc->caps.post_blend_color_processing = true;
	dc->caps.force_dp_tps4_for_cp2520 = true;
	dc->caps.extended_aux_timeout_support = true;
	dc->caps.dmcub_support = true;
	/* Color pipeline capabilities */
	dc->caps.color.dpp.dcn_arch = 1;
	dc->caps.color.dpp.input_lut_shared = 0;
	dc->caps.color.dpp.icsc = 1;
	dc->caps.color.dpp.dgam_ram = 0; // must use gamma_corr
	dc->caps.color.dpp.dgam_rom_caps.srgb = 1;
	dc->caps.color.dpp.dgam_rom_caps.bt2020 = 1;
	dc->caps.color.dpp.dgam_rom_caps.gamma2_2 = 1;
	dc->caps.color.dpp.dgam_rom_caps.pq = 1;
	dc->caps.color.dpp.dgam_rom_caps.hlg = 1;
	dc->caps.color.dpp.post_csc = 1;
	dc->caps.color.dpp.gamma_corr = 1;
	dc->caps.color.dpp.dgam_rom_for_yuv = 0;
	dc->caps.color.dpp.hw_3d_lut = 1;
	dc->caps.color.dpp.ogam_ram = 1;
	// no OGAM ROM on DCN301
	dc->caps.color.dpp.ogam_rom_caps.srgb = 0;
	dc->caps.color.dpp.ogam_rom_caps.bt2020 = 0;
	dc->caps.color.dpp.ogam_rom_caps.gamma2_2 = 0;
	dc->caps.color.dpp.ogam_rom_caps.pq = 0;
	dc->caps.color.dpp.ogam_rom_caps.hlg = 0;
	dc->caps.color.dpp.ocsc = 0;
	dc->caps.color.mpc.gamut_remap = 1;
	dc->caps.color.mpc.num_3dluts = pool->base.res_cap->num_mpc_3dlut; //2
	dc->caps.color.mpc.ogam_ram = 1;
	dc->caps.color.mpc.ogam_rom_caps.srgb = 0;
	dc->caps.color.mpc.ogam_rom_caps.bt2020 = 0;
	dc->caps.color.mpc.ogam_rom_caps.gamma2_2 = 0;
	dc->caps.color.mpc.ogam_rom_caps.pq = 0;
	dc->caps.color.mpc.ogam_rom_caps.hlg = 0;
	dc->caps.color.mpc.ocsc = 1;
	dc->caps.dp_hdmi21_pcon_support = true;
	/* read VBIOS LTTPR caps */
	if (ctx->dc_bios->funcs->get_lttpr_caps)  
		enum bp_result bp_query_result;
		uint8_t is_vbios_lttpr_enable = 0;
		bp_query_result = ctx->dc_bios->funcs->get_lttpr_caps(ctx->dc_bios, &is_vbios_lttpr_enable);
		dc->caps.vbios_lttpr_enable = (bp_query_result == BP_RESULT_OK) && !!is_vbios_lttpr_enable;
	 
	if (ctx->dc_bios->funcs->get_lttpr_interop)  
		enum bp_result bp_query_result;
		uint8_t is_vbios_interop_enabled = 0;
		bp_query_result = ctx->dc_bios->funcs->get_lttpr_interop(ctx->dc_bios, &is_vbios_interop_enabled);
		dc->caps.vbios_lttpr_aware = (bp_query_result == BP_RESULT_OK) && !!is_vbios_interop_enabled;
	 

Keep in mind that the documentation of color capabilities are available at the Linux kernel Documentation.

Understanding the development history: What has brought us to the current state? 9) Pinpoint relevant commits: Use git log and git blame to identify commits targeting the code section you re interested in. 10) Track regressions: If you re examining the amd-staging-drm-next branch, check for regressions between DC release versions. These are defined by DC_VER in the drivers/gpu/drm/amd/display/dc/dc.h file. Alternatively, find a commit with this format drm/amd/display: 3.2.221 that determines a display release. It s useful for bisecting. This information helps you understand how outdated your branch is and identify potential regressions. You can consider each DC_VER takes around one week to be bumped. Finally, check testing log of each release in the report provided on the amd-gfx mailing list, such as this one Tested-by: Daniel Wheeler:

• RE: [PATCH 00/13] DC Patches for Dec 11, 2023

Reducing the inspection area: Focus on what really matters. 11) Identify involved HW blocks: This helps isolate the issue. You can find more information about DCN HW blocks in the DCN Overview documentation. In summary:

• Plane issues are closer to HUBP and DPP.
• Blending/Stream issues are closer to MPC, OPP and OPTC. They are related to DRM CRTC subjects.

This information was useful when debugging a hardware rotation issue where the cursor plane got clipped off in the middle of the screen. Finally, the issue was addressed by two patches:

• [PATCH 21/22] drm/amd/display: Fix rotated cursor offset calculation
• [PATCH] drm/amd/display: fix cursor offset on rotation 180

12) Issues around bandwidth (glitches) and clocks: May be affected by calculations done in these HW blocks and HW specific values. The recalculation equations are found in the DML folder. DML stands for Display Mode Library. It s in charge of all required configuration parameters supported by the hardware for multiple scenarios. See more in the AMD DC Overview kernel docs. It s a math library that optimally configures hardware to find the best balance between power efficiency and performance in a given scenario. Finding some clk variables that affect device behavior may be a sign of it. It s hard for a external developer to debug this part, since it involves information from HW specs and firmware programming that we don t have access. The best option is to provide all relevant debugging information you have and ask AMD developers to check the values from your suspicions.

• Do a trick: If you suspect the power setup is degrading performance, try setting the amount of power supplied to the GPU to the maximum and see if it affects the system behavior with this command: sudo bash -c "echo high > /sys/class/drm/card0/device/power_dpm_force_performance_level"

I learned it when debugging glitches with hardware cursor rotation on Steam Deck. My first attempt was changing the clock calculation. In the end, Rodrigo Siqueira proposed the right solution targeting bandwidth in two steps:

• Patch series to create a new internal commit sequence
• Enabling pipe split on DCN301

Checking implicit programming and hardware limitations: Bring implicit programming to the level of consciousness and recognize hardware limitations. 13) Implicit update types: Check if the selected type for atomic update may affect your issue. The update type depends on the mode settings, since programming some modes demands more time for hardware processing. More details in the source code:

/* Surface update type is used by dc_update_surfaces_and_stream
 * The update type is determined at the very beginning of the function based
 * on parameters passed in and decides how much programming (or updating) is
 * going to be done during the call.
 *
 * UPDATE_TYPE_FAST is used for really fast updates that do not require much
 * logical calculations or hardware register programming. This update MUST be
 * ISR safe on windows. Currently fast update will only be used to flip surface
 * address.
 *
 * UPDATE_TYPE_MED is used for slower updates which require significant hw
 * re-programming however do not affect bandwidth consumption or clock
 * requirements. At present, this is the level at which front end updates
 * that do not require us to run bw_calcs happen. These are in/out transfer func
 * updates, viewport offset changes, recout size changes and pixel
depth changes.
 * This update can be done at ISR, but we want to minimize how often
this happens.
 *
 * UPDATE_TYPE_FULL is slow. Really slow. This requires us to recalculate our
 * bandwidth and clocks, possibly rearrange some pipes and reprogram
anything front
 * end related. Any time viewport dimensions, recout dimensions,
scaling ratios or
 * gamma need to be adjusted or pipe needs to be turned on (or
disconnected) we do
 * a full update. This cannot be done at ISR level and should be a rare event.
 * Unless someone is stress testing mpo enter/exit, playing with
colour or adjusting
 * underscan we don't expect to see this call at all.
 */
enum surface_update_type  
UPDATE_TYPE_FAST, /* super fast, safe to execute in isr */
UPDATE_TYPE_MED,  /* ISR safe, most of programming needed, no bw/clk change*/
UPDATE_TYPE_FULL, /* may need to shuffle resources */
 ;

Using tools: Observe the current state, validate your findings, continue improvements. 14) Use AMD tools to check hardware state and driver programming: help on understanding your driver settings and checking the behavior when changing those settings.

• DC Visual confirmation: Check multiple planes and pipe split policy.
• DTN logs: Check display hardware state, including rotation, size, format, underflow, blocks in use, color block values, etc.
• UMR: Check ASIC info, register values, KMS state - links and elements (framebuffers, planes, CRTCs, connectors). Source: UMR project documentation

15) Use generic DRM/KMS tools:

• IGT test tools: Use generic KMS tests or develop your own to isolate the issue in the kernel space. Compare results across different GPU vendors to understand their implementations and find potential solutions. Here AMD also has specific IGT tests for its GPUs that is expect to work without failures on any AMD GPU. You can check results of HW-specific tests using different display hardware families or you can compare expected differences between the generic workflow and AMD workflow.
• drm_info: This tool summarizes the current state of a display driver (capabilities, properties and formats) per element of the DRM/KMS workflow. Output can be helpful when reporting bugs.

Don t give up! Debugging issues in the AMD display driver can be challenging, but by following these tips and leveraging available resources, you can significantly improve your chances of success. Worth mentioning: This blog post builds upon my talk, I m not an AMD expert, but presented at the 2022 XDC. It shares guidelines that helped me debug AMD display issues as an external developer of the driver. Open Source Display Driver: The Linux kernel/AMD display driver is open source, allowing you to actively contribute by addressing issues listed in the official tracker. Tackling existing issues or resolving your own can be a rewarding learning experience and a valuable contribution to the community. Additionally, the tracker serves as a valuable resource for finding similar bugs, troubleshooting tips, and suggestions from AMD developers. Finally, it s a platform for seeking help when needed. Remember, contributing to the open source community through issue resolution and collaboration is mutually beneficial for everyone involved.

• A server with docker-compose installed
• An existing setup of nginx reverse proxy
• A domain name pointing to your server.

Step 1 : The docker-compose file for nextcloud AIOThe original compose.yml file is present in nextcloud AIO&aposs git repo here . By taking a reference of that file, we have own compose.yml here.

services:
  nextcloud-aio-mastercontainer:
    image: nextcloud/all-in-one:latest
    init: true
    restart: always
    container_name: nextcloud-aio-mastercontainer # This line is not allowed to be changed as otherwise AIO will not work correctly
    volumes:
      - nextcloud_aio_mastercontainer:/mnt/docker-aio-config # This line is not allowed to be changed as otherwise the built-in backup solution will not work
      - /var/run/docker.sock:/var/run/docker.sock:ro # May be changed on macOS, Windows or docker rootless. See the applicable documentation. If adjusting, don&apost forget to also set &aposWATCHTOWER_DOCKER_SOCKET_PATH&apos!
    ports:
      - 8080:8080
    environment: # Is needed when using any of the options below
      # - AIO_DISABLE_BACKUP_SECTION=false # Setting this to true allows to hide the backup section in the AIO interface. See https://github.com/nextcloud/all-in-one#how-to-disable-the-backup-section
      - APACHE_PORT=32323 # Is needed when running behind a web server or reverse proxy (like Apache, Nginx, Cloudflare Tunnel and else). See https://github.com/nextcloud/all-in-one/blob/main/reverse-proxy.md
      - APACHE_IP_BINDING=127.0.0.1 # Should be set when running behind a web server or reverse proxy (like Apache, Nginx, Cloudflare Tunnel and else) that is running on the same host. See https://github.com/nextcloud/all-in-one/blob/main/reverse-proxy.md
      # - BORG_RETENTION_POLICY=--keep-within=7d --keep-weekly=4 --keep-monthly=6 # Allows to adjust borgs retention policy. See https://github.com/nextcloud/all-in-one#how-to-adjust-borgs-retention-policy
      # - COLLABORA_SECCOMP_DISABLED=false # Setting this to true allows to disable Collabora&aposs Seccomp feature. See https://github.com/nextcloud/all-in-one#how-to-disable-collaboras-seccomp-feature
      - NEXTCLOUD_DATADIR=/opt/docker/cloud.raju.dev/nextcloud # Allows to set the host directory for Nextcloud&aposs datadir.   Warning: do not set or adjust this value after the initial Nextcloud installation is done! See https://github.com/nextcloud/all-in-one#how-to-change-the-default-location-of-nextclouds-datadir
      # - NEXTCLOUD_MOUNT=/mnt/ # Allows the Nextcloud container to access the chosen directory on the host. See https://github.com/nextcloud/all-in-one#how-to-allow-the-nextcloud-container-to-access-directories-on-the-host
      # - NEXTCLOUD_UPLOAD_LIMIT=10G # Can be adjusted if you need more. See https://github.com/nextcloud/all-in-one#how-to-adjust-the-upload-limit-for-nextcloud
      # - NEXTCLOUD_MAX_TIME=3600 # Can be adjusted if you need more. See https://github.com/nextcloud/all-in-one#how-to-adjust-the-max-execution-time-for-nextcloud
      # - NEXTCLOUD_MEMORY_LIMIT=512M # Can be adjusted if you need more. See https://github.com/nextcloud/all-in-one#how-to-adjust-the-php-memory-limit-for-nextcloud
      # - NEXTCLOUD_TRUSTED_CACERTS_DIR=/path/to/my/cacerts # CA certificates in this directory will be trusted by the OS of the nexcloud container (Useful e.g. for LDAPS) See See https://github.com/nextcloud/all-in-one#how-to-trust-user-defined-certification-authorities-ca
      # - NEXTCLOUD_STARTUP_APPS=deck twofactor_totp tasks calendar contacts notes # Allows to modify the Nextcloud apps that are installed on starting AIO the first time. See https://github.com/nextcloud/all-in-one#how-to-change-the-nextcloud-apps-that-are-installed-on-the-first-startup
      # - NEXTCLOUD_ADDITIONAL_APKS=imagemagick # This allows to add additional packages to the Nextcloud container permanently. Default is imagemagick but can be overwritten by modifying this value. See https://github.com/nextcloud/all-in-one#how-to-add-os-packages-permanently-to-the-nextcloud-container
      # - NEXTCLOUD_ADDITIONAL_PHP_EXTENSIONS=imagick # This allows to add additional php extensions to the Nextcloud container permanently. Default is imagick but can be overwritten by modifying this value. See https://github.com/nextcloud/all-in-one#how-to-add-php-extensions-permanently-to-the-nextcloud-container
      # - NEXTCLOUD_ENABLE_DRI_DEVICE=true # This allows to enable the /dev/dri device in the Nextcloud container.   Warning: this only works if the &apos/dev/dri&apos device is present on the host! If it should not exist on your host, don&apost set this to true as otherwise the Nextcloud container will fail to start! See https://github.com/nextcloud/all-in-one#how-to-enable-hardware-transcoding-for-nextcloud
      # - NEXTCLOUD_KEEP_DISABLED_APPS=false # Setting this to true will keep Nextcloud apps that are disabled in the AIO interface and not uninstall them if they should be installed. See https://github.com/nextcloud/all-in-one#how-to-keep-disabled-apps
      # - TALK_PORT=3478 # This allows to adjust the port that the talk container is using. See https://github.com/nextcloud/all-in-one#how-to-adjust-the-talk-port
      # - WATCHTOWER_DOCKER_SOCKET_PATH=/var/run/docker.sock # Needs to be specified if the docker socket on the host is not located in the default &apos/var/run/docker.sock&apos. Otherwise mastercontainer updates will fail. For macos it needs to be &apos/var/run/docker.sock&apos
    # networks: # Is needed when you want to create the nextcloud-aio network with ipv6-support using this file, see the network config at the bottom of the file
      # - nextcloud-aio # Is needed when you want to create the nextcloud-aio network with ipv6-support using this file, see the network config at the bottom of the file
      # - SKIP_DOMAIN_VALIDATION=true
    # # Uncomment the following line when using SELinux
    # security_opt: ["label:disable"]
volumes: # If you want to store the data on a different drive, see https://github.com/nextcloud/all-in-one#how-to-store-the-filesinstallation-on-a-separate-drive
  nextcloud_aio_mastercontainer:
    name: nextcloud_aio_mastercontainer # This line is not allowed to be changed as otherwise the built-in backup solution will not work

I have not removed many of the commented options in the compose file, for a possibility of me using them in the future.If you want a smaller cleaner compose with the extra options, you can refer to

services:
  nextcloud-aio-mastercontainer:
    image: nextcloud/all-in-one:latest
    init: true
    restart: always
    container_name: nextcloud-aio-mastercontainer
    volumes:
      - nextcloud_aio_mastercontainer:/mnt/docker-aio-config
      - /var/run/docker.sock:/var/run/docker.sock:ro
    ports:
      - 8080:8080
    environment:
      - APACHE_PORT=32323
      - APACHE_IP_BINDING=127.0.0.1
      - NEXTCLOUD_DATADIR=/opt/docker/nextcloud
volumes:
  nextcloud_aio_mastercontainer:
    name: nextcloud_aio_mastercontainer

I am using a separate directory to store nextcloud data. As per nextcloud documentation you should be using a separate partition if you want to use this feature, however I did not have that option on my server, so I used a separate directory instead. Also we use a custom port on which nextcloud listens for operations, we have set it up as 32323 above, but you can use any in the permissible port range. The 8080 port is used the setup the AIO management interface. Both 8080 and the APACHE_PORT do not need to be open on the host machine, as we will be using reverse proxy setup with nginx to direct requests. once you have your preferred compose.yml file, you can start the containers using

$ docker-compose -f compose.yml up -d 
Creating network "clouddev_default" with the default driver
Creating volume "nextcloud_aio_mastercontainer" with default driver
Creating nextcloud-aio-mastercontainer ... done

once your container&aposs are running, we can do the nginx setup.

Step 2: Configuring nginx reverse proxy for our domain on host. A reference nginx configuration for nextcloud AIO is given in the nextcloud git repository here . You can modify the configuration file according to your needs and setup. Here is configuration that we are using

map $http_upgrade $connection_upgrade  
    default upgrade;
    &apos&apos close;
 
server  
    listen 80;
    #listen [::]:80;            # comment to disable IPv6
    if ($scheme = "http")  
        return 301 https://$host$request_uri;
     
    listen 443 ssl http2;      # for nginx versions below v1.25.1
    #listen [::]:443 ssl http2; # for nginx versions below v1.25.1 - comment to disable IPv6
    # listen 443 ssl;      # for nginx v1.25.1+
    # listen [::]:443 ssl; # for nginx v1.25.1+ - keep comment to disable IPv6
    # http2 on;                                 # uncomment to enable HTTP/2        - supported on nginx v1.25.1+
    # http3 on;                                 # uncomment to enable HTTP/3 / QUIC - supported on nginx v1.25.0+
    # quic_retry on;                            # uncomment to enable HTTP/3 / QUIC - supported on nginx v1.25.0+
    # add_header Alt-Svc &aposh3=":443"; ma=86400' # uncomment to enable HTTP/3 / QUIC - supported on nginx v1.25.0+
    # listen 443 quic reuseport;       # uncomment to enable HTTP/3 / QUIC - supported on nginx v1.25.0+ - please remove "reuseport" if there is already another quic listener on port 443 with enabled reuseport
    # listen [::]:443 quic reuseport;  # uncomment to enable HTTP/3 / QUIC - supported on nginx v1.25.0+ - please remove "reuseport" if there is already another quic listener on port 443 with enabled reuseport - keep comment to disable IPv6
    server_name cloud.example.com;
    location /  
        proxy_pass http://127.0.0.1:32323$request_uri;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Port $server_port;
        proxy_set_header X-Forwarded-Scheme $scheme;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header Accept-Encoding "";
        proxy_set_header Host $host;
    
        client_body_buffer_size 512k;
        proxy_read_timeout 86400s;
        client_max_body_size 0;
        # Websocket
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection $connection_upgrade;
     
    ssl_certificate /etc/letsencrypt/live/cloud.example.com/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/cloud.example.com/privkey.pem; # managed by Certbot
    ssl_session_timeout 1d;
    ssl_session_cache shared:MozSSL:10m; # about 40000 sessions
    ssl_session_tickets off;
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-CHACHA20-POLY1305;
    ssl_prefer_server_ciphers on;
    # Optional settings:
    # OCSP stapling
    # ssl_stapling on;
    # ssl_stapling_verify on;
    # ssl_trusted_certificate /etc/letsencrypt/live/<your-nc-domain>/chain.pem;
    # replace with the IP address of your resolver
    # resolver 127.0.0.1; # needed for oscp stapling: e.g. use 94.140.15.15 for adguard / 1.1.1.1 for cloudflared or 8.8.8.8 for google - you can use the same nameserver as listed in your /etc/resolv.conf file
 

Please note that you need to have valid SSL certificates for your domain for this configuration to work. Steps on getting valid SSL certificates for your domain are beyond the scope of this article. You can give a web search on getting SSL certificates with letsencrypt and you will get several resources on that, or may write a blog post on it separately in the future.once your configuration for nginx is done, you can test the nginx configuration using

$ sudo nginx -t 
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful

and then reload nginx with

$ sudo nginx -s reload

Step 3: Setup of Nextcloud AIO from the browser.To setup nextcloud AIO, we need to access it using the web browser on URL of our domain.tld:8080, however we do not want to open the 8080 port publicly to do this, so to complete the setup, here is a neat hack from sahilister

ssh -L 8080:127.0.0.1:8080 username:<server-ip>

you can bind the 8080 port of your server to the 8080 of your localhost using Unix socket forwarding over SSH.The port forwarding only last for the duration of your SSH session, if the SSH session breaks, your port forwarding will to. So, once you have the port forwarded, you can open the nextcloud AIO instance in your web browser at 127.0.0.1:8080

you will get this error because you are trying to access a page on localhost over HTTPS. You can click on advanced and then continue to proceed to the next page. Your data is encrypted over SSH for this session as we are binding the port over SSH. Depending on your choice of browser, the above page might look different.once you have proceeded, the nextcloud AIO interface will open and will look something like this.

nextcloud AIO initial screen with capsicums as password

It will show an auto generated passphrase, you need to save this passphrase and make sure to not loose it. For the purposes of security, I have masked the passwords with capsicums. once you have noted down your password, you can proceed to the Nextcloud AIO login, enter your password and then login. After login you will be greeted with a screen like this.

now you can put the domain that you want to use in the Submit domain field. Once the domain check is done, you will proceed to the next step and see another screen like this

here you can select any optional containers for the features that you might want. IMPORTANT: Please make sure to also change the time zone at the bottom of the page according to the time zone you wish to operate in.

The timezone setup is also important because the data base will get initialized according to the set time zone. This could result in wrong initialization of database and you ending up in a startup loop for nextcloud. I faced this issue and could only resolve it after getting help from sahilister . Once you are done changing the timezone, and selecting any additional features you want, you can click on Download and start the containersIt will take some time for this process to finish, take a break and look at the farthest object in your room and take a sip of water. Once you are done, and the process has finished you will see a page similar to the following one.

wait patiently for everything to turn green.

once all the containers have started properly, you can open the nextcloud login interface on your configured domain, the initial login details are auto generated as you can see from the above screenshot. Again you will see a password that you need to note down or save to enter the nextcloud interface. Capsicums will not work as passwords. I have masked the auto generated passwords using capsicums.Now you can click on Open your Nextcloud button or go to your configured domain to access the login screen.

You can use the login details from the previous step to login to the administrator account of your Nextcloud instance. There you have it, your very own cloud!

Additional Notes:

How to properly reset Nextcloud setup?While following the above steps, or while following steps from some other tutorial, you may have made a mistake, and want to start everything again from scratch. The instructions for it are present in the Nextcloud documentation here . Here is the TLDR for a docker-compose setup. These steps will delete all data, do not use these steps on an existing nextcloud setup unless you know what you are doing.

• Stop your master container.

docker-compose -f compose.yml down -v

The above command will also remove the volume associated with the master container

• Stop all the child containers that has been started by the master container.

docker stop nextcloud-aio-apache nextcloud-aio-notify-push nextcloud-aio-nextcloud nextcloud-aio-imaginary nextcloud-aio-fulltextsearch nextcloud-aio-redis nextcloud-aio-database nextcloud-aio-talk nextcloud-aio-collabora

• Remove all the child containers that has been started by the master container

docker rm nextcloud-aio-apache nextcloud-aio-notify-push nextcloud-aio-nextcloud nextcloud-aio-imaginary nextcloud-aio-fulltextsearch nextcloud-aio-redis nextcloud-aio-database nextcloud-aio-talk nextcloud-aio-collabora

• If you also wish to remove all images associated with nextcloud you can do it with

docker rmi $(docker images --filter "reference=nextcloud/*" -q)

• remove all volumes associated with child containers

docker volume rm <volume-name>

• remove the network associated with nextcloud

docker network rm nextcloud-aio

Additional references.

1. Nextcloud Github
2. Nextcloud reverse proxy documentation
3. Nextcloud Administration Guide
4. Nextcloud User Manual
5. Nextcloud Developer&aposs manual

Debian LTS contributors In November, 18 contributors have been paid to work on Debian LTS, their reports are available:

• Abhijith PA did 7.0h (out of 0h assigned and 14.0h from previous period), thus carrying over 7.0h to the next month.
• Adrian Bunk did 15.0h (out of 14.0h assigned and 9.75h from previous period), thus carrying over 8.75h to the next month.
• Anton Gladky did 10.0h (out of 9.5h assigned and 5.5h from previous period), thus carrying over 5.0h to the next month.
• Bastien Roucari s did 16.0h (out of 18.25h assigned and 1.75h from previous period), thus carrying over 4.0h to the next month.
• Ben Hutchings did 12.0h (out of 16.5h assigned and 12.25h from previous period), thus carrying over 16.75h to the next month.
• Chris Lamb did 18.0h (out of 17.25h assigned and 0.75h from previous period).
• Emilio Pozuelo Monfort did 15.5h (out of 23.5h assigned and 0.25h from previous period), thus carrying over 8.25h to the next month.
• Guilhem Moulin did 13.0h (out of 12.0h assigned and 8.0h from previous period), thus carrying over 7.0h to the next month.
• Lee Garrett did 14.5h (out of 16.75h assigned and 7.0h from previous period), thus carrying over 9.25h to the next month.
• Markus Koschany did 30.0h (out of 30.0h assigned).
• Ola Lundqvist did 6.5h (out of 8.25h assigned and 15.5h from previous period), thus carrying over 17.25h to the next month.
• Roberto C. S nchez did 5.5h (out of 12.0h assigned), thus carrying over 6.5h to the next month.
• Santiago Ruano Rinc n did 3.25h (out of 13.62h assigned and 2.375h from previous period), thus carrying over 12.745h to the next month.
• Sean Whitton did 3.25h (out of 10.0h assigned), thus carrying over 6.75h to the next month.
• Sylvain Beucler did 10.0h (out of 13.5h assigned and 10.25h from previous period), thus carrying over 13.75h to the next month.
• Thorsten Alteholz did 14.0h (out of 14.0h assigned).
• Tobias Frost did 12.0h (out of 12.0h assigned).
• Utkarsh Gupta did 0.0h (out of 6.0h assigned and 17.75h from previous period), thus carrying over 23.75h to the next month.

Evolution of the situation In November, we have released 35 DLAs.

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

• Platinum sponsors:
  • TOSHIBA (for 99 months)
  • Civil Infrastructure Platform (CIP) (for 67 months)
• Gold sponsors:
  • Roche Diagnostics International AG (for 110 months)
  • Linode (for 104 months)
  • Babiel GmbH (for 93 months)
  • Plat Home (for 93 months)
  • University of Oxford (for 49 months)
  • Deveryware (for 36 months)
  • VyOS Inc (for 31 months)
  • EDF SA (for 20 months)
• Silver sponsors:
  • Domeneshop AS (for 114 months)
  • Nantes M tropole (for 108 months)
  • Univention GmbH (for 100 months)
  • Universit Jean Monnet de St Etienne (for 100 months)
  • Ribbon Communications, Inc. (for 94 months)
  • Exonet B.V. (for 84 months)
  • Leibniz Rechenzentrum (for 78 months)
  • CINECA (for 67 months)
  • Minist re de l Europe et des Affaires trang res (for 61 months)
  • Cloudways Ltd (for 51 months)
  • Dinahosting SL (for 49 months)
  • Bauer Xcel Media Deutschland KG (for 43 months)
  • Platform.sh SAS (for 43 months)
  • Moxa Inc. (for 37 months)
  • sipgate GmbH (for 34 months)
  • OVH US LLC (for 32 months)
  • Tilburg University (for 32 months)
  • GSI Helmholtzzentrum f r Schwerionenforschung GmbH (for 23 months)
  • Soliton Systems K.K. (for 21 months)
• Bronze sponsors:
  • Evolix (for 115 months)
  • Seznam.cz, a.s. (for 115 months)
  • Intevation GmbH (for 112 months)
  • Linuxhotel GmbH (for 112 months)
  • Daevel SARL (for 110 months)
  • Bitfolk LTD (for 109 months)
  • Megaspace Internet Services GmbH (for 109 months)
  • Greenbone AG (for 108 months)
  • NUMLOG (for 108 months)
  • WinGo AG (for 108 months)
  • Ecole Centrale de Nantes - LHEEA (for 104 months)
  • Entr ouvert (for 99 months)
  • Adfinis AG (for 96 months)
  • GNI MEDIA (for 91 months)
  • Laboratoire LEGI - UMR 5519 / CNRS (for 91 months)
  • Tesorion (for 91 months)
  • Bearstech (for 82 months)
  • LiHAS (for 82 months)
  • Catalyst IT Ltd (for 77 months)
  • Supagro (for 72 months)
  • Demarcq SAS (for 71 months)
  • Universit Grenoble Alpes (for 57 months)
  • TouchWeb SAS (for 49 months)
  • SPiN AG (for 46 months)
  • CoreFiling (for 41 months)
  • Institut des sciences cognitives Marc Jeannerod (for 36 months)
  • Observatoire des Sciences de l Univers de Grenoble (for 33 months)
  • Tem Innovations GmbH (for 27 months)
  • WordFinder.pro (for 27 months)
  • CNRS DT INSU R sif (for 26 months)
  • Alter Way (for 19 months)
  • Institut Camille Jordan (for 8 months)

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

Changes

• tracer: mention needrestart
• duck: add inactive project indicator
• Debian wiki pages: AutoGeneratedFiles, CopyrightReviewTools, CornerCase, CrossGrading, DeveloperNews, Hardware/Wanted, InstallingDebianOn/SiFive/HiFiveUnmatched
• FOSSjobs wiki pages: Resources
• vcs-home wiki: add more dotfile repos/tools

Issues

• Files in wrong dir in git-cola
• Conffile removal needed in dkms
• New SWH listers needed for HGKeeper, Smithy, humungus, git-arr, gitile, gotweb, ABF, Bonobo Git Server, darcsden

Review

• Debian packages: sponsored purple-discord x2
• Debian wiki: RecentChanges for the month
• Debian BTS usertags: changes for the month
• Debian screenshots:
  • approved c-evo-dh-gtk2 fim fish foliate mpc123 nfoview qpwgraph scite viewnior
  • rejected hw-probe (photos), wine64 (desktop logo), phasex (artwork), qpwgraph (about dialog), fim/fish (help output), python-lunch (full desktop), ruby-full (website), ausweisapp2 (PII), pngtools (movie poster), x11vnc (web page,) mount (systemd), blastem (photo), ca-certificates (tiny, Windows)

Administration

• Debian servers: extract user data from recent wiki backups
• Debian wiki: fix broken user account, approve accounts

Communication

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

Sponsors The SWH work was sponsored. All other work was done on a volunteer basis.

Motivation
Andy (RattusRattus) and I have been formalising instructions for using Pete Batard's version of Tianocore (and therefore UEFI booting) for the Raspberry Pi 4 together with a Debian arm64 netinst to make a modified Debian installer on a USB stick which "just works" for a Raspberry Pi 4.
Thanks also to Steve McIntyre for initial notes that got this working for us and also to Emmanuele Rocca for putting up some useful instructions for copying.

Recipe

Plug in a USB stick - use dmesg or your favourite method to see how it is identified.

Make a couple of mount points under /mnt - /mnt/data and /mnt/cdrom

1. Grab a USB stick, Partition using MBR. Make a single VFAT
partition, type 0xEF (i.e. EFI System Partition)

For a USB stick (identified as sdX) below:
$ sudo parted --script /dev/sdX mklabel msdos $ sudo parted --script /dev/sdX mkpart primary fat32 0% 100% $ sudo mkfs.vfat /dev/sdX1 $ sudo mount /dev/sdX1 /mnt/data/

Download an arm64 netinst.iso

https://cdimage.debian.org/debian-cd/current/arm64/iso-cd/debian-12.2.0-arm64-netinst.iso

2. Copy the complete contents of partition *1* from a Debian arm64
installer image into the filesystem (partition 1 is the installer
stuff itself) on the USB stick, in /

$ sudo kpartx -v -a debian-12.2.0-arm64-netinst.iso # Mount the first partition on the ISO and copy its contents to the stick $ sudo mount /dev/mapper/loop0p1 /mnt/cdrom/ $ sudo rsync -av /mnt/cdrom/ /mnt/data/ $ sudo umount /mnt/cdrom

3. Copy the complete contents of partition *2* from that Debian arm64
installer image into that filesystem (partition 2 is the ESP) on
the USB stick, in /

# Same story with the second partition on the ISO

$ sudo mount /dev/mapper/loop0p2 /mnt/cdrom/

$ sudo rsync -av /mnt/cdrom/ /mnt/data/ $ sudo umount /mnt/cdrom

$ sudo kpartx -d debian-testing-amd64-netinst.iso $ sudo umount /mnt/data

4. Grab the rpi edk2 build from https://github.com/pftf/RPi4/releases
(I used 1.35) and extract it. I copied the files there into *2*
places for now on the USB stick:

/ (so the Pi will boot using it)
/rpi4 (so we can find the files again later)

5. Add the preseed.cfg file (attached) into *both* of the two initrd
files on the USB stick

- /install.a64/initrd.gz and
- /install.a64/gtk/initrd.gz

cpio is an awful tool to use :-(. In each case:

$ cp /path/to/initrd.gz .
$ gunzip initrd.gz
$ echo preseed.cfg cpio -H newc -o -A -F initrd

$ gzip -9v initrd

$ cp initrd.gz /path/to/initrd.gz

If you look at the preseed file, it will do a few things:

- Use an early_command to unmount /media (to work around Debian bug
#1051964)

- Register a late_command call for /cdrom/finish-rpi (the next
file - see below) to run at the end of the installation.

- Force grub installation also to the EFI removable media path,
needed as the rpi doesn't store EFI boot variables.

- Stop the installer asking for firmware from removable media (as
the rpi4 will ask for broadcom bluetooth fw that we can't
ship. Can be ignored safely.)

6. Copy the finish-rpi script (attached) into / on the USB stick. It
will be run at the end of the installation, triggered via the
preseed. It does a couple of things:

- Copy the edk2 firmware files into the ESP on the system that's
just been installer

- Remove shim-signed from the installed systems, as there's a bug
that causes it to fail on rpi4. I need to dig into this to see
what the issue is.

That's it! Run the installer as normal, all should Just Work (TM).

BlueTooth didn't quite work : raspberrypi-firmware didn't install until adding a symlink for boot/efi to /boot/firmware

20231127 - This may not be necessary because raspberrypi-firmware path has been fixed

Preseed.cfg
# The preseed file itself causes a problem - the installer medium is
# left mounted on /medis so things break in cdrom-detect. Let's see if
# we can fix that!
d-i preseed/early_command string umount /media true

# Run our command to do rpi setup before reboot
d-i preseed/late_command string /cdrom/finish-rpi

# Force grub installation to the RM path
grub-efi-arm64 grub2/force_efi_extra_removable boolean true

# Don't prompt for missing firmware from removable media,
# e.g. broadcom bluetooth on the rpi.
d-i hw-detect/load_firmware boolean false

Finish.rpi
!/bin/sh

set -x

grep -q -a RPI4 /sys/firmware/acpi/tables/CSRT
if [ $? -ne 0 ]; then
echo "Not running on a Pi 4, exit!"
exit 0
fi

# Copy the rpi4 firmware binaries onto the installed system.
# Assumes the installer media is mounted on /cdrom.
cp -vr /cdrom/rpi4/. /target/boot/efi/.

# shim-signed doesn't seem happy on rpi4, so remove it
mount --bind /sys /target/sys
mount --bind /proc /target/proc
mount --bind /dev /target/dev

in-target apt-get remove --purge --autoremove -y shim-signed

Reproducible Builds Summit 2023 Between October 31st and November 2nd, we held our seventh Reproducible Builds Summit in Hamburg, Germany! Our summits are a unique gathering that brings together attendees from diverse projects, united by a shared vision of advancing the Reproducible Builds effort, and this instance was no different. During this enriching event, participants had the opportunity to engage in discussions, establish connections and exchange ideas to drive progress in this vital field. A number of concrete outcomes from the summit will documented in the report for November 2023 and elsewhere. Amazingly the agenda and all notes from all sessions are already online. The Reproducible Builds team would like to thank our event sponsors who include Mullvad VPN, openSUSE, Debian, Software Freedom Conservancy, Allotropia and Aspiration Tech.

Reflections on Reflections on Trusting Trust Russ Cox posted a fascinating article on his blog prompted by the fortieth anniversary of Ken Thompson s award-winning paper, Reflections on Trusting Trust:

[ ] In March 2023, Ken gave the closing keynote [and] during the Q&A session, someone jokingly asked about the Turing award lecture, specifically can you tell us right now whether you have a backdoor into every copy of gcc and Linux still today?

Although Ken reveals (or at least claims!) that he has no such backdoor, he does admit that he has the actual code which Russ requests and subsequently dissects in great but accessible detail.

Ecosystem factors of reproducible builds Rahul Bajaj, Eduardo Fernandes, Bram Adams and Ahmed E. Hassan from the Maintenance, Construction and Intelligence of Software (MCIS) laboratory within the School of Computing, Queen s University in Ontario, Canada have published a paper on the Time to fix, causes and correlation with external ecosystem factors of unreproducible builds. The authors compare various response times within the Debian and Arch Linux distributions including, for example:

Arch Linux packages become reproducible a median of 30 days quicker when compared to Debian packages, while Debian packages remain reproducible for a median of 68 days longer once fixed.

A full PDF of their paper is available online, as are many other interesting papers on MCIS publication page.

NixOS installation image reproducible On the NixOS Discourse instance, Arnout Engelen (raboof) announced that NixOS have created an independent, bit-for-bit identical rebuilding of the nixos-minimal image that is used to install NixOS. In their post, Arnout details what exactly can be reproduced, and even includes some of the history of this endeavour:

You may remember a 2021 announcement that the minimal ISO was 100% reproducible. While back then we successfully tested that all packages that were needed to build the ISO were individually reproducible, actually rebuilding the ISO still introduced differences. This was due to some remaining problems in the hydra cache and the way the ISO was created. By the time we fixed those, regressions had popped up (notably an upstream problem in Python 3.10), and it isn t until this week that we were back to having everything reproducible and being able to validate the complete chain.

Congratulations to NixOS team for reaching this important milestone! Discussion about this announcement can be found underneath the post itself, as well as on Hacker News.

CPython source tarballs now reproducible Seth Larson published a blog post investigating the reproducibility of the CPython source tarballs. Using diffoscope, reprotest and other tools, Seth documents his work that led to a pull request to make these files reproducible which was merged by ukasz Langa.

New arm64 hardware from Codethink Long-time sponsor of the project, Codethink, have generously replaced our old Moonshot-Slides , which they have generously hosted since 2016 with new KVM-based arm64 hardware. Holger Levsen integrated these new nodes to the Reproducible Builds continuous integration framework.

Community updates On our mailing list during October 2023 there were a number of threads, including:

• Vagrant Cascadian continued a thread about the implementation details of a snapshot archive server required for reproducing previous builds. [ ]
• Akihiro Suda shared an update on BuildKit, a toolkit for building Docker container images. Akihiro links to a interesting talk they recently gave at DockerCon titled Reproducible builds with BuildKit for software supply-chain security.
• Alex Zakharov started a thread discussing and proposing fixes for various tools that create ext4 filesystem images. [ ]

Elsewhere, Pol Dellaiera made a number of improvements to our website, including fixing typos and links [ ][ ], adding a NixOS Flake file [ ] and sorting our publications page by date [ ]. Vagrant Cascadian presented Reproducible Builds All The Way Down at the Open Source Firmware Conference.

Distribution work distro-info is a Debian-oriented tool that can provide information about Debian (and Ubuntu) distributions such as their codenames (eg. bookworm) and so on. This month, Benjamin Drung uploaded a new version of distro-info that added support for the SOURCE_DATE_EPOCH environment variable in order to close bug #1034422. In addition, 8 reviews of packages were added, 74 were updated and 56 were removed this month, all adding to our knowledge about identified issues. Bernhard M. Wiedemann published another monthly report about reproducibility within openSUSE.

Software development 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:

• Bernhard M. Wiedemann:
  • edje_cc (race condition)
  • elasticsearch (build failure)
  • erlang-retest (embedded .zip timestamp)
  • fdo-client (embeds private keys)
  • fftw3 (random ordering)
  • gsoap (date issue)
  • gutenprint (date)
  • hub/golang (embeds random build path)
  • Hyprland (filesystem issue)
  • kitty (sort-related issue, .tar file embeds modification time)
  • libpinyin (ASLR)
  • maildir-utils (date embedded in copyright)
  • mame (order-related issue)
  • mingw32-binutils & mingw64-binutils (date)
  • MooseX (date from perl-MooseX-App)
  • occt (sorting issue)
  • openblas (embeds CPU count)
  • OpenRGB (corruption-related issue)
  • python-numpy (random file names)
  • python-pandas (FTBFS)
  • python-quantities (date)
  • python3-pyside2 (order)
  • qemu (date and Sphinx issue)
  • qpid (sorting problem)
  • rakudo (filesystem ordering issue)
  • SLOF (date-related issue)
  • spack (CPU counting issue)
  • xemacs-packages (date-related issue)
• Chris Lamb:
  • #1053353 filed against dacite.
  • #1053356 filed against rtpengine.

In addition, Chris Lamb fixed an issue in diffoscope, where if the equivalent of file -i returns text/plain, fallback to comparing as a text file. This was originally filed as Debian bug #1053668) by Niels Thykier. [ ] This was then uploaded to Debian (and elsewhere) as version 251.

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 October, a number of changes were made by Holger Levsen:

• Debian-related changes:
  • Refine the handling of package blacklisting, such as sending blacklisting notifications to the #debian-reproducible-changes IRC channel. [ ][ ][ ]
  • Install systemd-oomd on all Debian bookworm nodes (re. Debian bug #1052257). [ ]
  • Detect more cases of failures to delete schroots. [ ]
  • Document various bugs in bookworm which are (currently) being manually worked around. [ ]
• Node-related changes:
  • Integrate the new arm64 machines from Codethink. [ ][ ][ ][ ][ ][ ]
  • Improve various node cleanup routines. [ ][ ][ ][ ]
  • General node maintenance. [ ][ ][ ][ ]
• Monitoring-related changes:
  • Remove unused Munin monitoring plugins. [ ]
  • Complain less visibly about too many installed kernels. [ ]
• Misc:
  • Enhance the firewall handling on Jenkins nodes. [ ][ ][ ][ ]
  • Install the fish shell everywhere. [ ]

In addition, Vagrant Cascadian added some packages and configuration for snapshot experiments. [ ]

---

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:

• IRC: #reproducible-builds on irc.oftc.net.
• Mailing list: rb-general@lists.reproducible-builds.org
• Mastodon: @reproducible_builds
• Twitter: @ReproBuilds

TL;DR: This blog post explores the color capabilities of AMD hardware and how they are exposed to userspace through driver-specific properties. It discusses the different color blocks in the AMD Display Core Next (DCN) pipeline and their capabilities, such as predefined transfer functions, 1D and 3D lookup tables (LUTs), and color transformation matrices (CTMs). It also highlights the differences in AMD HW blocks for pre and post-blending adjustments, and how these differences are reflected in the available driver-specific properties. Overall, this blog post provides a comprehensive overview of the color capabilities of AMD hardware and how they can be controlled by userspace applications through driver-specific properties. This information is valuable for anyone who wants to develop applications that can take advantage of the AMD color management pipeline. Get a closer look at each hardware block s capabilities, unlock a wealth of knowledge about AMD display hardware, and enhance your understanding of graphics and visual computing. Stay tuned for future developments as we embark on a quest for GPU color capabilities in the ever-evolving realm of rainbow treasures.

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Operating Systems can use the power of GPUs to ensure consistent color reproduction across graphics devices. We can use GPU-accelerated color management to manage the diversity of color profiles, do color transformations to convert between High-Dynamic-Range (HDR) and Standard-Dynamic-Range (SDR) content and color enhacements for wide color gamut (WCG). However, to make use of GPU display capabilities, we need an interface between userspace and the kernel display drivers that is currently absent in the Linux/DRM KMS API. In the previous blog post I presented how we are expanding the Linux/DRM color management API to expose specific properties of AMD hardware. Now, I ll guide you to the color features for the Linux/AMD display driver. We embark on a journey through DRM/KMS, AMD Display Manager, and AMD Display Core and delve into the color blocks to uncover the secrets of color manipulation within AMD hardware. Here we ll talk less about the color tools and more about where to find them in the hardware. We resort to driver-specific properties to reach AMD hardware blocks with color capabilities. These blocks display features like predefined transfer functions, color transformation matrices, and 1-dimensional (1D LUT) and 3-dimensional lookup tables (3D LUT). Here, we will understand how these color features are strategically placed into color blocks both before and after blending in Display Pipe and Plane (DPP) and Multiple Pipe/Plane Combined (MPC) blocks. That said, welcome back to the second part of our thrilling journey through AMD s color management realm!

AMD Display Driver in the Linux/DRM Subsystem: The Journey In my 2022 XDC talk I m not an AMD expert, but , I briefly explained the organizational structure of the Linux/AMD display driver where the driver code is bifurcated into a Linux-specific section and a shared-code portion. To reveal AMD s color secrets through the Linux kernel DRM API, our journey led us through these layers of the Linux/AMD display driver s software stack. It includes traversing the DRM/KMS framework, the AMD Display Manager (DM), and the AMD Display Core (DC) [1]. The DRM/KMS framework provides the atomic API for color management through KMS properties represented by struct drm_property. We extended the color management interface exposed to userspace by leveraging existing resources and connecting them with driver-specific functions for managing modeset properties. On the AMD DC layer, the interface with hardware color blocks is established. The AMD DC layer contains OS-agnostic components that are shared across different platforms, making it an invaluable resource. This layer already implements hardware programming and resource management, simplifying the external developer s task. While examining the DC code, we gain insights into the color pipeline and capabilities, even without direct access to specifications. Additionally, AMD developers provide essential support by answering queries and reviewing our work upstream. The primary challenge involved identifying and understanding relevant AMD DC code to configure each color block in the color pipeline. However, the ultimate goal was to bridge the DC color capabilities with the DRM API. For this, we changed the AMD DM, the OS-dependent layer connecting the DC interface to the DRM/KMS framework. We defined and managed driver-specific color properties, facilitated the transport of user space data to the DC, and translated DRM features and settings to the DC interface. Considerations were also made for differences in the color pipeline based on hardware capabilities.

Exploring Color Capabilities of the AMD display hardware Now, let s dive into the exciting realm of AMD color capabilities, where a abundance of techniques and tools await to make your colors look extraordinary across diverse devices. First, we need to know a little about the color transformation and calibration tools and techniques that you can find in different blocks of the AMD hardware. I borrowed some images from [2] [3] [4] to help you understand the information.

Predefined Transfer Functions (Named Fixed Curves): Transfer functions serve as the bridge between the digital and visual worlds, defining the mathematical relationship between digital color values and linear scene/display values and ensuring consistent color reproduction across different devices and media. You can learn more about curves in the chapter GPU Gems 3 - The Importance of Being Linear by Larry Gritz and Eugene d Eon. ITU-R 2100 introduces three main types of transfer functions:

• OETF: the opto-electronic transfer function, which converts linear scene light into the video signal, typically within a camera.
• EOTF: electro-optical transfer function, which converts the video signal into the linear light output of the display.
• OOTF: opto-optical transfer function, which has the role of applying the rendering intent .

AMD s display driver supports the following pre-defined transfer functions (aka named fixed curves):

• Linear/Unity: linear/identity relationship between pixel value and luminance value;
• Gamma 2.2, Gamma 2.4, Gamma 2.6: pure power functions;
• sRGB: 2.4: The piece-wise transfer function from IEC 61966-2-1:1999;
• BT.709: has a linear segment in the bottom part and then a power function with a 0.45 (~1/2.22) gamma for the rest of the range; standardized by ITU-R BT.709-6;
• PQ (Perceptual Quantizer): used for HDR display, allows luminance range capability of 0 to 10,000 nits; standardized by SMPTE ST 2084.

These capabilities vary depending on the hardware block, with some utilizing hardcoded curves and others relying on AMD s color module to construct curves from standardized coefficients. It also supports user/custom curves built from a lookup table.

1D LUTs (1-dimensional Lookup Table): A 1D LUT is a versatile tool, defining a one-dimensional color transformation based on a single parameter. It s very well explained by Jeremy Selan at GPU Gems 2 - Chapter 24 Using Lookup Tables to Accelerate Color Transformations It enables adjustments to color, brightness, and contrast, making it ideal for fine-tuning. In the Linux AMD display driver, the atomic API offers a 1D LUT with 4096 entries and 8-bit depth, while legacy gamma uses a size of 256.

3D LUTs (3-dimensional Lookup Table): These tables work in three dimensions red, green, and blue. They re perfect for complex color transformations and adjustments between color channels. It s also more complex to manage and require more computational resources. Jeremy also explains 3D LUT at GPU Gems 2 - Chapter 24 Using Lookup Tables to Accelerate Color Transformations

CTM (Color Transformation Matrices): Color transformation matrices facilitate the transition between different color spaces, playing a crucial role in color space conversion.

HDR Multiplier: HDR multiplier is a factor applied to the color values of an image to increase their overall brightness.

AMD Color Capabilities in the Hardware Pipeline First, let s take a closer look at the AMD Display Core Next hardware pipeline in the Linux kernel documentation for AMDGPU driver - Display Core Next In the AMD Display Core Next hardware pipeline, we encounter two hardware blocks with color capabilities: the Display Pipe and Plane (DPP) and the Multiple Pipe/Plane Combined (MPC). The DPP handles color adjustments per plane before blending, while the MPC engages in post-blending color adjustments. In short, we expect DPP color capabilities to match up with DRM plane properties, and MPC color capabilities to play nice with DRM CRTC properties. Note: here s the catch there are some DRM CRTC color transformations that don t have a corresponding AMD MPC color block, and vice versa. It s like a puzzle, and we re here to solve it!

AMD Color Blocks and Capabilities We can finally talk about the color capabilities of each AMD color block. As it varies based on the generation of hardware, let s take the DCN3+ family as reference. What s possible to do before and after blending depends on hardware capabilities describe in the kernel driver by struct dpp_color_caps and struct mpc_color_caps. The AMD Steam Deck hardware provides a tangible example of these capabilities. Therefore, we take SteamDeck/DCN301 driver as an example and look at the Color pipeline capabilities described in the file: driver/gpu/drm/amd/display/dcn301/dcn301_resources.c

/* Color pipeline capabilities */
dc->caps.color.dpp.dcn_arch = 1; // If it is a Display Core Next (DCN): yes. Zero means DCE.
dc->caps.color.dpp.input_lut_shared = 0;
dc->caps.color.dpp.icsc = 1; // Intput Color Space Conversion  (CSC) matrix.
dc->caps.color.dpp.dgam_ram = 0; // The old degamma block for degamma curve (hardcoded and LUT).  Gamma correction  is the new one.
dc->caps.color.dpp.dgam_rom_caps.srgb = 1; // sRGB hardcoded curve support
dc->caps.color.dpp.dgam_rom_caps.bt2020 = 1; // BT2020 hardcoded curve support (seems not actually in use)
dc->caps.color.dpp.dgam_rom_caps.gamma2_2 = 1; // Gamma 2.2 hardcoded curve support
dc->caps.color.dpp.dgam_rom_caps.pq = 1; // PQ hardcoded curve support
dc->caps.color.dpp.dgam_rom_caps.hlg = 1; // HLG hardcoded curve support
dc->caps.color.dpp.post_csc = 1; // CSC matrix
dc->caps.color.dpp.gamma_corr = 1; // New  Gamma Correction  block for degamma user LUT;
dc->caps.color.dpp.dgam_rom_for_yuv = 0;
dc->caps.color.dpp.hw_3d_lut = 1; // 3D LUT support. If so, it's always preceded by a shaper curve. 
dc->caps.color.dpp.ogam_ram = 1; //  Blend Gamma  block for custom curve just after blending
// no OGAM ROM on DCN301
dc->caps.color.dpp.ogam_rom_caps.srgb = 0;
dc->caps.color.dpp.ogam_rom_caps.bt2020 = 0;
dc->caps.color.dpp.ogam_rom_caps.gamma2_2 = 0;
dc->caps.color.dpp.ogam_rom_caps.pq = 0;
dc->caps.color.dpp.ogam_rom_caps.hlg = 0;
dc->caps.color.dpp.ocsc = 0;
dc->caps.color.mpc.gamut_remap = 1; // Post-blending CTM (pre-blending CTM is always supported)
dc->caps.color.mpc.num_3dluts = pool->base.res_cap->num_mpc_3dlut; // Post-blending 3D LUT (preceded by shaper curve)
dc->caps.color.mpc.ogam_ram = 1; // Post-blending regamma.
// No pre-defined TF supported for regamma.
dc->caps.color.mpc.ogam_rom_caps.srgb = 0;
dc->caps.color.mpc.ogam_rom_caps.bt2020 = 0;
dc->caps.color.mpc.ogam_rom_caps.gamma2_2 = 0;
dc->caps.color.mpc.ogam_rom_caps.pq = 0;
dc->caps.color.mpc.ogam_rom_caps.hlg = 0;
dc->caps.color.mpc.ocsc = 1; // Output CSC matrix.

I included some inline comments in each element of the color caps to quickly describe them, but you can find the same information in the Linux kernel documentation. See more in struct dpp_color_caps, struct mpc_color_caps and struct rom_curve_caps. Now, using this guideline, we go through color capabilities of DPP and MPC blocks and talk more about mapping driver-specific properties to corresponding color blocks.

DPP Color Pipeline: Before Blending (Per Plane) Let s explore the capabilities of DPP blocks and what you can achieve with a color block. The very first thing to pay attention is the display architecture of the display hardware: previously AMD uses a display architecture called DCE

• Display and Compositing Engine, but newer hardware follows DCN - Display Core Next.

The architectute is described by: dc->caps.color.dpp.dcn_arch

AMD Plane Degamma: TF and 1D LUT Described by: dc->caps.color.dpp.dgam_ram, dc->caps.color.dpp.dgam_rom_caps,dc->caps.color.dpp.gamma_corr AMD Plane Degamma data is mapped to the initial stage of the DPP pipeline. It is utilized to transition from scanout/encoded values to linear values for arithmetic operations. Plane Degamma supports both pre-defined transfer functions and 1D LUTs, depending on the hardware generation. DCN2 and older families handle both types of curve in the Degamma RAM block (dc->caps.color.dpp.dgam_ram); DCN3+ separate hardcoded curves and 1D LUT into two block: Degamma ROM (dc->caps.color.dpp.dgam_rom_caps) and Gamma correction block (dc->caps.color.dpp.gamma_corr), respectively. Pre-defined transfer functions:

• they are hardcoded curves (read-only memory - ROM);
• supported curves: sRGB EOTF, BT.709 inverse OETF, PQ EOTF and HLG OETF, Gamma 2.2, Gamma 2.4 and Gamma 2.6 EOTF.

The 1D LUT currently accepts 4096 entries of 8-bit. The data is interpreted as an array of struct drm_color_lut elements. Setting TF = Identity/Default and LUT as NULL means bypass. References:

• [PATCH v3 04/32] drm/amd/display: add driver-specific property for plane degamma LUT
• [PATCH v3 05/32] drm/amd/display: add plane degamma TF driver-specific property
• [PATCH v3 19/32] drm/amd/display: add plane degamma TF and LUT support

AMD Plane 3x4 CTM (Color Transformation Matrix) AMD Plane CTM data goes to the DPP Gamut Remap block, supporting a 3x4 fixed point (s31.32) matrix for color space conversions. The data is interpreted as a struct drm_color_ctm_3x4. Setting NULL means bypass. References:

• [PATCH v3 30/32] drm/amd/display: add plane CTM driver-specific property
• [PATCH v3 31/32] drm/amd/display: add plane CTM support
• [PATCH v3 32/32] drm/amd/display: Add 3x4 CTM support for plane CTM

AMD Plane Shaper: TF + 1D LUT Described by: dc->caps.color.dpp.hw_3d_lut The Shaper block fine-tunes color adjustments before applying the 3D LUT, optimizing the use of the limited entries in each dimension of the 3D LUT. On AMD hardware, a 3D LUT always means a preceding shaper 1D LUT used for delinearizing and/or normalizing the color space before applying a 3D LUT, so this entry on DPP color caps dc->caps.color.dpp.hw_3d_lut means support for both shaper 1D LUT and 3D LUT. Pre-defined transfer function enables delinearizing content with or without shaper LUT, where AMD color module calculates the resulted shaper curve. Shaper curves go from linear values to encoded values. If we are already in a non-linear space and/or don t need to normalize values, we can set a Identity TF for shaper that works similar to bypass and is also the default TF value. Pre-defined transfer functions:

• there is no DPP Shaper ROM. Curves are calculated by AMD color modules. Check calculate_curve() function in the file amd/display/modules/color/color_gamma.c.
• supported curves: Identity, sRGB inverse EOTF, BT.709 OETF, PQ inverse EOTF, HLG OETF, and Gamma 2.2, Gamma 2.4, Gamma 2.6 inverse EOTF.

The 1D LUT currently accepts 4096 entries of 8-bit. The data is interpreted as an array of struct drm_color_lut elements. When setting Plane Shaper TF (!= Identity) and LUT at the same time, the color module will combine the pre-defined TF and the custom LUT values into the LUT that s actually programmed. Setting TF = Identity/Default and LUT as NULL works as bypass. References:

• [PATCH v3 10/32] drm/amd/display: add plane shaper LUT and TF
• [PATCH v3 23/32] drm/amd/display: add plane shaper LUT support
• [PATCH v3 24/32] drm/amd/display: add plane shaper TF support

AMD Plane 3D LUT Described by: dc->caps.color.dpp.hw_3d_lut The 3D LUT in the DPP block facilitates complex color transformations and adjustments. 3D LUT is a three-dimensional array where each element is an RGB triplet. As mentioned before, the dc->caps.color.dpp.hw_3d_lut describe if DPP 3D LUT is supported. The AMD driver-specific property advertise the size of a single dimension via LUT3D_SIZE property. Plane 3D LUT is a blog property where the data is interpreted as an array of struct drm_color_lut elements and the number of entries is LUT3D_SIZE cubic. The array contains samples from the approximated function. Values between samples are estimated by tetrahedral interpolation The array is accessed with three indices, one for each input dimension (color channel), blue being the outermost dimension, red the innermost. This distribution is better visualized when examining the code in [RFC PATCH 5/5] drm/amd/display: Fill 3D LUT from userspace by Alex Hung:

+	for (nib = 0; nib < 17; nib++)  
+		for (nig = 0; nig < 17; nig++)  
+			for (nir = 0; nir < 17; nir++)  
+				ind_lut = 3 * (nib + 17*nig + 289*nir);
+
+				rgb_area[ind].red = rgb_lib[ind_lut + 0];
+				rgb_area[ind].green = rgb_lib[ind_lut + 1];
+				rgb_area[ind].blue = rgb_lib[ind_lut + 2];
+				ind++;
+			 
+		 
+	 

In our driver-specific approach we opted to advertise it s behavior to the userspace instead of implicitly dealing with it in the kernel driver. AMD s hardware supports 3D LUTs with 17-size or 9-size (4913 and 729 entries respectively), and you can choose between 10-bit or 12-bit. In the current driver-specific work we focus on enabling only 17-size 12-bit 3D LUT, as in [PATCH v3 25/32] drm/amd/display: add plane 3D LUT support:

+		/* Stride and bit depth are not programmable by API yet.
+		 * Therefore, only supports 17x17x17 3D LUT (12-bit).
+		 */
+		lut->lut_3d.use_tetrahedral_9 = false;
+		lut->lut_3d.use_12bits = true;
+		lut->state.bits.initialized = 1;
+		__drm_3dlut_to_dc_3dlut(drm_lut, drm_lut3d_size, &lut->lut_3d,
+					lut->lut_3d.use_tetrahedral_9,
+					MAX_COLOR_3DLUT_BITDEPTH);

A refined control of 3D LUT parameters should go through a follow-up version or generic API. Setting 3D LUT to NULL means bypass. References:

• [PATCH v3 09/32] drm/amd/display: add plane 3D LUT driver-specific properties
• [PATCH v3 25/32] drm/amd/display: add plane 3D LUT support

AMD Plane Blend/Out Gamma: TF + 1D LUT Described by: dc->caps.color.dpp.ogam_ram The Blend/Out Gamma block applies the final touch-up before blending, allowing users to linearize content after 3D LUT and just before the blending. It supports both 1D LUT and pre-defined TF. We can see Shaper and Blend LUTs as 1D LUTs that are sandwich the 3D LUT. So, if we don t need 3D LUT transformations, we may want to only use Degamma block to linearize and skip Shaper, 3D LUT and Blend. Pre-defined transfer function:

• there is no DPP Blend ROM. Curves are calculated by AMD color modules;
• supported curves: Identity, sRGB EOTF, BT.709 inverse OETF, PQ EOTF, HLG inverse OETF, and Gamma 2.2, Gamma 2.4, Gamma 2.6 EOTF.

The 1D LUT currently accepts 4096 entries of 8-bit. The data is interpreted as an array of struct drm_color_lut elements. If plane_blend_tf_property != Identity TF, AMD color module will combine the user LUT values with pre-defined TF into the LUT parameters to be programmed. Setting TF = Identity/Default and LUT to NULL means bypass. References:

• [PATCH v3 11/32] drm/amd/display: add plane blend
• [PATCH v3 27/32] drm/amd/display: add plane blend LUT and TF support

MPC Color Pipeline: After Blending (Per CRTC)

DRM CRTC Degamma 1D LUT The degamma lookup table (LUT) for converting framebuffer pixel data before apply the color conversion matrix. The data is interpreted as an array of struct drm_color_lut elements. Setting NULL means bypass. Not really supported. The driver is currently reusing the DPP degamma LUT block (dc->caps.color.dpp.dgam_ram and dc->caps.color.dpp.gamma_corr) for supporting DRM CRTC Degamma LUT, as explaning by [PATCH v3 20/32] drm/amd/display: reject atomic commit if setting both plane and CRTC degamma.

DRM CRTC 3x3 CTM Described by: dc->caps.color.mpc.gamut_remap It sets the current transformation matrix (CTM) apply to pixel data after the lookup through the degamma LUT and before the lookup through the gamma LUT. The data is interpreted as a struct drm_color_ctm. Setting NULL means bypass.

DRM CRTC Gamma 1D LUT + AMD CRTC Gamma TF Described by: dc->caps.color.mpc.ogam_ram After all that, you might still want to convert the content to wire encoding. No worries, in addition to DRM CRTC 1D LUT, we ve got a AMD CRTC gamma transfer function (TF) to make it happen. Possible TF values are defined by enum amdgpu_transfer_function. Pre-defined transfer functions:

• there is no MPC Gamma ROM. Curves are calculated by AMD color modules.
• supported curves: Identity, sRGB inverse EOTF, BT.709 OETF, PQ inverse EOTF, HLG OETF, and Gamma 2.2, Gamma 2.4, Gamma 2.6 inverse EOTF.

The 1D LUT currently accepts 4096 entries of 8-bit. The data is interpreted as an array of struct drm_color_lut elements. When setting CRTC Gamma TF (!= Identity) and LUT at the same time, the color module will combine the pre-defined TF and the custom LUT values into the LUT that s actually programmed. Setting TF = Identity/Default and LUT to NULL means bypass. References:

• [PATCH v3 12/32] drm/amd/display: add CRTC gamma TF driver-specific property
• [PATCH v3 15/32] drm/amd/display: add CRTC gamma TF support

Others

AMD CRTC Shaper and 3D LUT We have previously worked on exposing CRTC shaper and CRTC 3D LUT, but they were removed from the AMD driver-specific color series because they lack userspace case. CRTC shaper and 3D LUT works similar to plane shaper and 3D LUT but after blending (MPC block). The difference here is that setting (not bypass) Shaper and Gamma blocks together are not expected, since both blocks are used to delinearize the input space. In summary, we either set Shaper + 3D LUT or Gamma.

Input and Output Color Space Conversion There are two other color capabilities of AMD display hardware that were integrated to DRM by previous works and worth a brief explanation here. The DC Input CSC sets pre-defined coefficients from the values of DRM plane color_range and color_encoding properties. It is used for color space conversion of the input content. On the other hand, we have de DC Output CSC (OCSC) sets pre-defined coefficients from DRM connector colorspace properties. It is uses for color space conversion of the composed image to the one supported by the sink. References:

• [PATCH] amd/display/dc: Fix COLOR_ENCODING and COLOR_RANGE doing nothing for DCN20+
• [PATCH v6 00/13] Enable Colorspace connector property in amdgpu

The search for rainbow treasures is not over yet If you want to understand a little more about this work, be sure to watch Joshua and I presented two talks at XDC 2023 about AMD/Steam Deck colors on Gamescope:

• The rainbow treasure map: advanced color management on Linux with AMD/Steam Deck
• Rainbow Frogs: HDR + Color Management in Gamescope/SteamOS

In the time between the first and second part of this blog post, Uma Shashank and Chaitanya Kumar Borah published the plane color pipeline for Intel and Harry Wentland implemented a generic API for DRM based on VKMS support. We discussed these two proposals and the next steps for Color on Linux during the Color Management workshop at XDC 2023 and I briefly shared workshop results in the 2023 XDC lightning talk session. The search for rainbow treasures is not over yet! We plan to meet again next year in the 2024 Display Hackfest in Coru a-Spain (Igalia s HQ) to keep up the pace and continue advancing today s display needs on Linux. Finally, a HUGE thank you to everyone who worked with me on exploring AMD s color capabilities and making them available in userspace.

DebCamp I planned to spend DebCamp working on various issues. Very few of them actually got done, I spent the first few days in bed further recovering, took a covid-19 test when I arrived and after I felt better, and both were negative, so not sure what exactly was wrong with me, but between that and catching up with other Debian duties, I couldn t make any progress on catching up on the packaging work I wanted to do. I ll still post what I intended here, I ll try to take a few days to focus on these some time next month: Calamares / Debian Live stuff:

• #980209 installation fails at the install boot loader phase
• #1021156 calamares-settings-debian: Confusing/generic program names
• #1037299 Install Debian -> Untrusted application launcher
• #1037123 Minimal HD space required too small for some live images
• #971003 Console auto-login doesn t work with sysvinit

At least Calamares has been trixiefied in testing, so there s that! Desktop stuff:

• #1038660 please set a placeholder theme during development, different from any release
• #1021816 breeze: Background image not shown any more
• #956102 desktop-base: unwanted metadata within images
• #605915 please mtheake it a non-native package
• #681025 Put old themes in a new package named desktop-base-extra
• #941642 desktop-base: split theme data files and desktop integrations in separate packages

The Egg theme that I want to develop for testing/unstable is based on Juliette Taka s Homeworld theme that was used for Bullseye. Egg, as in, something that hasn t quite hatched yet. Get it? (for #1038660) Debian Social:

• Set up Lemmy instance
  • I started setting up a Lemmy instance before DebCamp, and meant to finish it.
• Migrate PeerTube to new server
  • We got a new physical server for our PeerTube instance, we should have more space for growth and it would help us fix the streaming feature on our platform.

Loopy: I intended to get the loop for DebConf in good shape before I left, so that we can spend some time during DebCamp making some really nice content, unfortunately this went very tumbly, but at least we ended up with a loopy that kind of worked and wasn t too horrible. There s always another DebConf to try again, right?

So DebCamp as a usual DebCamp was pretty much a wash (fitting with all the rain we had?) for me, at least it gave me enough time to recover a bit for DebConf proper, and I had enough time left to catch up on some critical DPL duties and put together a few slides for the Bits from the DPL talk.

DebConf Bits From the DPL I had very, very little available time to prepare something for Bits fro the DPL, but I managed to put some slides together (available on my wiki page). I mostly covered:

• A very quick introduction of myself (I ve done this so many times, it feels redundant giving my history every time), and some introduction on what it is that the DPL does. I declared my intent not to run for DPL again, and the reasoning behind it, and a few bits of information for people who may intend to stand for DPL next year.
• The sentiment out there for the Debian 12 release (which has been very positive). How we include firmware by default now, and that we re saying goodbye to architectures both GNU/KFreeBSD and mipsel.
• Debian Day and the 30th birthday party celebrations from local groups all over the world (and a reminder about the Local Groups BoF later in the week).
• I looked forward to Debian 13 (trixie!), and how we re gaining riscv64 as a release architecture, as well as loongarch64, and that plans seem to be forming to fix 2k38 in Debian, and hopefully largely by the time the Trixie release comes by.
• I made some comments about Enterprise Linux as people refer to the RHEL eco-system these days, how really bizarre some aspects of it is (like the kernel maintenance), and that some big vendors are choosing to support systems outside of that eco-system now (like CPanel now supporting Ubuntu too). I closed with the quote below from Ian Murdock, and assured the audience that if they want to go out and make money with Debian, they are more than welcome too.

Job Fair I walked through the hallway where the Job Fair was hosted, and enjoyed all the buzz. It s not always easy to get this right, but this year it was very active and energetic, I hope lots of people made some connections! Cheese & Wine Due to state laws and alcohol licenses, we couldn t consume alcohol from outside the state of Kerala in the common areas of the hotel (only in private rooms), so this wasn t quite as big or as fun as our usual C&W parties since we couldn t share as much from our individual countries and cultures, but we always knew that this was going to be the case for this DebConf, and it still ended up being alright. Day Trip I opted for the forest / waterfalls daytrip. It was really, really long with lots of time in the bus. I think our trip s organiser underestimated how long it would take between the points on the route (all in all it wasn t that far, but on a bus on a winding mountain road, it takes long). We left at 8:00 and only found our way back to the hotel around 23:30. Even though we arrived tired and hungry, we saw some beautiful scenery, animals and also met indigenous river people who talked about their struggles against being driven out of their place of living multiple times as government invests in new developments like dams and hydro power.

Photos available in the DebConf23 public git repository. Losing a beloved Debian Developer during DebConf To our collective devastation, not everyone made it back from their day trips. Abraham Raji was out to the kayak day trip, and while swimming, got caught by a whirlpool from a drainage system. Even though all of us were properly exhausted and shocked in disbelief at this point, we had to stay up and make some tough decisions. Some initially felt that we had to cancel the rest of DebConf. We also had to figure out how to announce what happened asap both to the larger project and at DebConf in an official manner, while ensuring that due diligence took place and that the family is informed by the police first before making anything public. We ended up cancelling all the talks for the following day, with an address from the DPL in the morning to explain what had happened. Of all the things I ve ever had to do as DPL, this was by far the hardest. The day after that, talks were also cancelled for the morning so that we could attend his funeral. Dozens of DebConf attendees headed out by bus to go pay their final respects, many wearing the t-shirts that Abraham had designed for DebConf. A book of condolences was set up so that everyone who wished to could write a message on how they remembered him. The book will be kept by his family.

Today marks a week since his funeral, and I still feel very raw about it. And even though there was uncertainty whether DebConf should even continue after his death, in hindsight I m glad that everyone pushed forward. While we were all heart broken, it was also heart warming to see people care for each other in all of this. If anything, I think I needed more time at DebConf just to be in that warm aura of emotional support for just a bit longer. There are many people who I wanted to talk to who I barely even had a chance to see. Abraham, or Abru as he was called by some people (which I like because bru in Afrikaans is like bro in English, not sure if that s what it implied locally too) enjoyed artistic pursuits, but he was also passionate about knowledge transfer. He ran classes at DebConf both last year and this year (and I think at other local events too) where he taught people packaging via a quick course that he put together. His enthusiasm for Debian was contagious, a few of the people who he was mentoring came up to me and told me that they were going to see it through and become a DD in honor of him. I can t even remember how I reacted to that, my brain was already so worn out and stitching that together with the tragedy of what happened while at DebConf was just too much for me. I first met him in person last year in Kosovo, I already knew who he was, so I think we interacted during the online events the year before. He was just one of those people who showed so much promise, and I was curious to see what he d achieve in the future. Unfortunately, we was taken away from us too soon. Poetry Evening Later in the week we had the poetry evening. This was the first time I had the courage to recite something. I read Ithaka by C.P. Cavafy (translated by Edmund Keely). The first time I heard about this poem was in an interview with Julian Assange s wife, where she mentioned that he really loves this poem, and it caught my attention because I really like the Weezer song Return to Ithaka and always wondered what it was about, so needless to say, that was another rabbit hole at some point. Group Photo Our DebConf photographer organised another group photo for this event, links to high-res versions available on Aigar s website.

BoFs I didn t attend nearly as many talks this DebConf as I would ve liked (fortunately I can catch up on video, should be released soon), but I did make it to a few BoFs. In the Local Groups BoF, representatives from various local teams were present who introduced themselves and explained what they were doing. From memory (sorry if I left someone out), we had people from Belgium, Brazil, Taiwan and South Africa. We talked about types of events a local group could do (BSPs, Mini DC, sprints, Debian Day, etc. How to help local groups get started, booth kits for conferences, and setting up some form of calendar that lists important Debian events in a way that makes it easier for people to plan and co-ordinate. There s a mailing list for co-ordination of local groups, and the irc channel is #debian-localgroups on oftc.

If you got one of these Cheese & Wine bags from DebConf, that s from the South African local group!

In the Debian.net BoF, we discussed the Debian.net hosting service, where Debian pays for VMs hosted for projects by individual DDs on Debian.net. The idea is that we start some form of census that monitors the services, whether they re still in use, whether the system is up to date, whether someone still cares for it, etc. We had some discussion about where the lines of responsibility are drawn, and we can probably make things a little bit more clear in the documentation. We also want to offer more in terms of backups and monitoring (currently DDs do get 500GB from rsync.net that could be used for backups of their services though). The intention is also to deploy some form of configuration management for some essentials across the hosts. We should also look at getting some sponsored hosting for this. In the Debian Social BoF, we discussed some services that need work / expansion. In particular, Matrix keeps growing at an increased rate as more users use it and more channels are bridged, so it will likely move to its own host with big disks soon. We might replace Pleroma with a fork called Akkoma, this will need some more home work and checking whether it s even feasible. Some services haven t really been used (like Writefreely and Plume), and it might be time to retire them. We might just have to help one or two users migrate some of their posts away if we do retire them. Mjolner seems to do a fine job at spam blocking, we haven t had any notable incidents yet. WordPress now has improved fediverse support, it s unclear whether it works on a multi-site instance yet, I ll test it at some point soon and report back. For upcoming services, we are implementing Lemmy and probably also Mobilizon. A request was made that we also look into Loomio. More Information Overload There s so much that happens at DebConf, it s tough to take it all in, and also, to find time to write about all of it, but I ll mention a few more things that are certainly worth of note. During DebConf, we had some people from the Kite Linux team over. KITE supplies the ICT needs for the primary and secondary schools in the province of Kerala, where they all use Linux. They decided to switch all of these to Debian. There was an ad-hoc BoF where locals were listening and fielding questions that the Kite Linux team had. It was great seeing all the energy and enthusiasm behind this effort, I hope someone will properly blog about this! I learned about the VGLUG Foundation, who are doing a tremendous job at promoting GNU/Linux in the country. They are also training up 50 people a year to be able to provide tech support for Debian. I came across the booth for Mostly Harmless, they liberate old hardware by installing free firmware on there. It was nice seeing all the devices out there that could be liberated, and how it can breathe new life into old harware.

Some hopefully harmless soldering.

Overall, the community and their activities in India are very impressive, and I wish I had more time to get to know everyone better. Food Oh yes, one more thing. The food was great. I tasted more different kinds of curry than I ever did in my whole life up to this point. The lunch on banana leaves was interesting, and also learning how to eat this food properly by hand (thanks to the locals who insisted on teaching me!), it was a fruitful experience? This might catch on at home too less dishes to take care of!

Special thanks to the DebConf23 Team I think this may have been one of the toughest DebConfs to organise yet, and I don t think many people outside of the DebConf team knows about all the challenges and adversity this team has faced in organising it. Even just getting to the previous DebConf in Kosovo was a long and tedious and somewhat risky process. Through it all, they were absolute pro s. Not once did I see them get angry or yell at each other, whenever a problem came up, they just dealt with it. They did a really stellar job and I did make a point of telling them on the last day that everyone appreciated all the work that they did. Back to my nest I bought Dax a ball back from India, he seems to have forgiven me for not taking him along.

I ll probably take a few days soon to focus a bit on my bugs and catch up on my original DebCamp goals. If you made it this far, thanks for reading! And thanks to everyone for being such fantastic people.

/usr-merge work, by Helmut Grohne, et al. Given that we now have consensus on moving forward by moving aliased files from / to /usr, we will also run into the problems that the file move moratorium was meant to prevent. The way forward is detecting them early and applying workarounds on a per-package basis. Said detection is now automated using the Debian Usr Merge Analysis Tool. As problems are reported to the bug tracking system, they are connected to the reports if properly usertagged. Bugs and patches for problem categories DEP17-P2 and DEP17-P6 have been filed. After consensus has been reached on the bootstrapping matters, debootstrap has been changed to swap the initial unpack and merging to avoid unpack errors due to pre-existing links. This is a precondition for having base-files install the aliasing symbolic links eventually. It was identified that the root filesystem used by the Debian installer is still unmerged and a change has been proposed. debhelper was changed to recognize systemd units installed to /usr. A discussion with the CTTE and release team on repealing the moratorium has been initiated.

Salsa CI work, by Santiago Ruano Rinc n August was a busy month in the Salsa CI world. Santiago reviewed and merged a bunch of MRs that have improved the project in different aspects: The aptly job got two MRs from Philip Hands. With the first one, the aptly now can export a couple of variables in a dotenv file, and with the second, it can include packages from multiple artifact directories. These MRs bring the base to improve how to test reverse dependencies with Salsa CI. Santiago is working on documenting this. As a result of the mass bug filing done in August, Salsa CI now includes a job to test how a package builds twice in a row. Thanks to the MRs of Sebastiaan Couwenberg and Johannes Schauer Marin Rodrigues. Last but not least, Santiago helped Johannes Schauer Marin Rodrigues to complete the support for arm64-only pipelines.

DebConf23 lead-up, by Stefano Rivera Stefano wears a few hats in the DebConf organization and in the lead up to the conference in mid-September, they ve all been quite busy. As one of the treasurers of DebConf 23, there has been a final budget update, and quite a few payments to coordinate from Debian s Trusted Organizations. We try to close the books from the previous conference at the next one, so a push was made to get DebConf 22 account statements out of TOs and record them in the conference ledger. As a website developer, we had a number of registration-related tasks, emailing attendees and trying to estimate numbers for food and accommodation. As a conference committee member, the job was mostly taking calls and helping the local team to make decisions on urgent issues. For example, getting conference visas issued to attendees required getting political approval from the Indian government. We only discovered the full process for this too late to clear some complex cases, so this required some hard calls on skipping some countries from the application list, allowing everyone else to get visas in time. Unfortunate, but necessary.

Miscellaneous contributions

• Rapha l Hertzog updated gnome-shell-extension-hamster to a new upstream git snapshot that is compatible with GNOME Shell 44 that was recently uploaded to Debian unstable/testing. This extension makes it easy to start/stop tracking time with Hamster Time Tracker. Very handy for consultants like us who are billing their work per hour.
• Rapha l also updated zim to the latest upstream release (0.74.2). This is a desktop wiki that can be very useful as a note-taking tool to build your own personal knowledge base or even to manage your personal todo lists.
• Utkarsh reviewed and sponsored some uploads from mentors.debian.net.
• Utkarsh helped the local team and the bursary team with some more DebConf activities and helped finalize the data.
• Thorsten tried to update package hplip. Unfortunately upstream added some new compressed files that need to appear uncompressed in the package. Even though this sounded like an easy task, which seemed to be already implemented in the current debian/rules, the new type of files broke this implementation and made the package no longer buildable. The problem has been solved and the upload will happen soon.
• Helmut sent 7 patches for cross build failures. Since dpkg-buildflags now defaults to issue arm64-specific compiler flags, more care is needed to distinguish between build architecture flags and host architecture flags than previously.
• Stefano pushed the final bit of the tox 4 transition over the line in Debian, allowing dh-python and tox 4 to migrate to testing. We got caught up in a few unusual bugs in tox and the way we run it in Debian package building (which had to change with tox 4). This resulted in a couple of patches upstream.
• Stefano visited Haifa, Israel, to see the proposed DebConf 24 venue and meet with the local team. While the venue isn t committed yet, we have high hopes for it.

Welcome to the August 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 quick 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. The motivation behind the reproducible builds effort is to ensure no flaws have been introduced during this compilation process by promising identical results are always generated from a given source, thus allowing multiple third-parties to come to a consensus on whether a build was compromised. If you are interested in contributing to the project, please visit our Contribute page on our website.

Rust serialisation library moving to precompiled binaries Bleeping Computer reported that Serde, a popular Rust serialization framework, had decided to ship its serde_derive macro as a precompiled binary. As Ax Sharma writes:

The move has generated a fair amount of push back among developers who worry about its future legal and technical implications, along with a potential for supply chain attacks, should the maintainer account publishing these binaries be compromised.

After intensive discussions, use of the precompiled binary was phased out.

Reproducible builds, the first ten years On August 4th, Holger Levsen gave a talk at BornHack 2023 on the Danish island of Funen titled Reproducible Builds, the first ten years which promised to contain:

[ ] an overview about reproducible builds, the past, the presence and the future. How it started with a small [meeting] at DebConf13 (and before), how it grew from being a Debian effort to something many projects work on together, until in 2021 it was mentioned in an executive order of the president of the United States. (HTML slides)

Holger repeated the talk later in the month at Chaos Communication Camp 2023 in Zehdenick, Germany: A video of the talk is available online, as are the HTML slides.

Reproducible Builds Summit Just another reminder that our upcoming Reproducible Builds Summit is set to take place from October 31st November 2nd 2023 in Hamburg, Germany. Our summits are a unique gathering that brings together attendees from diverse projects, united by a shared vision of advancing the Reproducible Builds effort. During this enriching event, participants will have the opportunity to engage in discussions, establish connections and exchange ideas to drive progress in this vital field. If you re interested in joining us this year, please make sure to read the event page, the news item, or the invitation email that Mattia Rizzolo sent out, which have more details about the event and location. We are also still looking for sponsors to support the event, so do reach out to the organizing team if you are able to help. (Also of note that PackagingCon 2023 is taking place in Berlin just before our summit, and their schedule has just been published.)

Vagrant Cascadian on the Sustain podcast Vagrant Cascadian was interviewed on the SustainOSS podcast on reproducible builds:

Vagrant walks us through his role in the project where the aim is to ensure identical results in software builds across various machines and times, enhancing software security and creating a seamless developer experience. Discover how this mission, supported by the Software Freedom Conservancy and a broad community, is changing the face of Linux distros, Arch Linux, openSUSE, and F-Droid. They also explore the challenges of managing random elements in software, and Vagrant s vision to make reproducible builds a standard best practice that will ideally become automatic for users. Vagrant shares his work in progress and their commitment to the last mile problem.

The episode is available to listen (or download) from the Sustain podcast website. As it happens, the episode was recorded at FOSSY 2023, and the video of Vagrant s talk from this conference (Breaking the Chains of Trusting Trust is now available on Archive.org: It was also announced that Vagrant Cascadian will be presenting at the Open Source Firmware Conference in October on the topic of Reproducible Builds All The Way Down.

On our mailing list Carles Pina i Estany wrote to our mailing list during August with an interesting question concerning the practical steps to reproduce the hello-traditional package from Debian. The entire thread can be viewed from the archive page, as can Vagrant Cascadian s reply.

Website updates Rahul Bajaj updated our website to add a series of environment variations related to reproducible builds [ ], Russ Cox added the Go programming language to our projects page [ ] and Vagrant Cascadian fixed a number of broken links and typos around the website [ ][ ][ ].

Software development In diffoscope development this month, versions 247, 248 and 249 were uploaded to Debian unstable by Chris Lamb, who also added documentation for the new specialize_as method and expanding the documentation of the existing specialize as well [ ]. In addition, Fay Stegerman added specialize_as and used it to optimise .smali comparisons when decompiling Android .apk files [ ], Felix Yan and Mattia Rizzolo corrected some typos in code comments [ , ], Greg Chabala merged the RUN commands into single layer in the package s Dockerfile [ ] thus greatly reducing the final image size. Lastly, Roland Clobus updated tool descriptions to mark that the xb-tool has moved package within Debian [ ].
reprotest is our tool for building the same source code twice in different environments and then checking the binaries produced by each build for any differences. This month, Vagrant Cascadian updated the packaging to be compatible with Tox version 4. This was originally filed as Debian bug #1042918 and Holger Levsen uploaded this to change to Debian unstable as version 0.7.26 [ ].

Distribution work In Debian, 28 reviews of Debian packages were added, 14 were updated and 13 were removed this month adding to our knowledge about identified issues. A number of issue types were added, including Chris Lamb adding a new timestamp_in_documentation_using_sphinx_zzzeeksphinx_theme toolchain issue.
In August, F-Droid added 25 new reproducible apps and saw 2 existing apps switch to reproducible builds, making 191 apps in total that are published with Reproducible Builds and using the upstream developer s signature. [ ]
Bernhard M. Wiedemann published another monthly report about reproducibility within openSUSE.

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:

• Bernhard M. Wiedemann:
  • arimo (modification time in build results)
  • apptainer (random Go build identifier)
  • arrow (fails to build on single-CPU machines)
  • camlp (parallelism-related issue)
  • developer (Go ordering-related issue)
  • elementary-xfce-icon-theme (font-related problem)
  • gegl (parallelism issue)
  • grommunio (filesystem ordering issue)
  • grpc (drop nondetermistic log)
  • guile-parted (parallelism-related issue)
  • icinga (hostname-based issue)
  • liquid-dsp (CPU-oriented problem)
  • memcached (package fails to build far in the future)
  • openmpi5/openpmix (date/copyright year issue)
  • openmpi5 (date/copyright year issue)
  • orthanc-ohif+orthanc-volview (ordering related issue plus timestamp in a Gzip)
  • perl-Net-DNS (package fails to build far in the future)
  • postgis (parallelism issue)
  • python-scipy (uses an arbitrary build path)
  • python-trustme (package fails to build far in the future)
  • qtbase/qmake/goldendict-ng (timestamp-related issue)
  • qtox (date-related issue)
  • ring (filesytem ordering related issue)
  • scipy (1 & 2) (drop arbtirary build path and filesytem-ordering issue)
  • snimpy (1 & 3) (fails to build on single-CPU machines as well far in the future)
  • tango-icon-theme (font-related issue)
• Chris Lamb:
  • #1042954 filed against libcerf.
  • #1042955 filed against zzzeeksphinx.
  • #1043330 filed against tox.
  • #1050357 filed against pytds.
  • #1050727 filed against zlib.
  • #1050944 filed against jtreg6.
  • #1050955 filed against rpy2.
• Rebecca N. Palmer:
  • #1050619 filed against nbclient.

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 August, a number of changes were made by Holger Levsen:

• Debian-related changes:
  • Disable Debian live image creation jobs until an OpenQA credential problem has been fixed. [ ]
  • Run our maintenance scripts every 3 hours instead of every 2. [ ]
  • Export data for unstable to the reproducible-tracker.json data file. [ ]
  • Stop varying the build path, we want reproducible builds. [ ]
  • Temporarily stop updating the pbuilder.tgz for Debian unstable due to #1050784. [ ][ ]
  • Correctly document that we are not variying usrmerge. [ ][ ]
  • Mark two armhf nodes (wbq0 and jtx1a) as down; investigation is needed. [ ]
• Misc:
  • Force reconfiguration of all Jenkins jobs, due to the recent rise of zombie processes. [ ]
  • In the node health checks, also try to restart failed ntpsec, postfix and vnstat services. [ ][ ][ ]
• System health checks:
  • Detect Debian live build failures due to missing credentials. [ ][ ]
  • Ignore specific types of known zombie processes. [ ][ ]

In addition, Vagrant Cascadian updated the scripts to use a predictable build path that is consistent with the one used on buildd.debian.org. [ ][ ]

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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:

• IRC: #reproducible-builds on irc.oftc.net.
• Mailing list: rb-general@lists.reproducible-builds.org
• Mastodon: @reproducible_builds@fosstodon.org
• Twitter: @ReproBuilds