Search Results: "fw"

10 March 2024

Valhalla's Things: Low Fat, No Eggs, Lasagna-ish

Posted on March 10, 2024
Tags: madeof:atoms, craft:cooking
A few notes on what we had for lunch, to be able to repeat it after the summer. There were a number of food intolerance related restrictions which meant that the traditional lasagna recipe wasn t an option; the result still tasted good, but it was a bit softer and messier to take out of the pan and into the dishes. On Saturday afternoon we made fresh no-egg pasta with 200 g (durum) flour and 100 g water, after about 1 hour it was divided in 6 parts and rolled to thickness #6 on the pasta machine. Meanwhile, about 500 ml of low fat almost-rag -like meat sauce was taken out of the freezer: this was a bit too little, 750 ml would have been better. On Saturday evening we made a sauce with 1 l of low-fat milk and 80 g of flour, and the meat sauce was heated up. Then everything was put in a 28 cm 23 cm pan, with 6 layers of pasta and 7 layers of the two sauces, and left to cool down. And on Sunday morning it was baked for 35 min in the oven at 180 C. With 3 people we only had about two thirds of it. Next time I think we should try to use 400 - 500 g of flour (so that it s easier to work by machine), 2 l of milk, 1.5 l of meat sauce and divide it into 3 pans: one to eat the next day and two to freeze (uncooked) for another day. No pictures, because by the time I thought about writing a post we were already more than halfway through eating it :)

3 March 2024

Paul Wise: FLOSS Activities Feb 2024

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

Changes

Issues

Review
  • Spam: reported 1 Debian bug report
  • Debian BTS usertags: changes for the month

Administration
  • Debian BTS: unarchive/reopen/triage bugs for reintroduced packages: ovito, tahoe-lafs, tpm2-tss-engine
  • Debian wiki: produce HTML dump for a user, unblock IP addresses, 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.

1 February 2024

Russ Allbery: Review: System Collapse

Review: System Collapse, by Martha Wells
Series: Murderbot Diaries #7
Publisher: Tordotcom
Copyright: 2023
ISBN: 1-250-82698-5
Format: Kindle
Pages: 245
System Collapse is the second Murderbot novel. Including the novellas, it's the 7th in the series. Unlike Fugitive Telemetry, the previous novella that was out of chronological order, this is the direct sequel to Network Effect. A very direct sequel; it picks up just a few days after the previous novel ended. Needless to say, you should not start here. I was warned by other people and therefore re-read Network Effect immediately before reading System Collapse. That was an excellent idea, since this novel opens with a large cast, no dramatis personae, not much in the way of a plot summary, and a lot of emotional continuity from the previous novel. I would grumble about this more, like I have in other reviews, but I thoroughly enjoyed re-reading Network Effect and appreciated the excuse.
ART-drone said, I wouldn t recommend it. I lack a sense of proportional response. I don t advise engaging with me on any level.
Saying much about the plot of this book without spoiling Network Effect and the rest of the series is challenging. Murderbot is suffering from the aftereffects of the events of the previous book more than it expected or would like to admit. It and its humans are in the middle of a complicated multi-way negotiation with some locals, who the corporates are trying to exploit. One of the difficulties in that negotiation is getting people to believe that the corporations are as evil as they actually are, a plot element that has a depressing amount in common with current politics. Meanwhile, Murderbot is trying to keep everyone alive. I loved Network Effect, but that was primarily for the social dynamics. The planet that was central to the novel was less interesting, so another (short) novel about the same planet was a bit of a disappointment. This does give Wells a chance to show in more detail what Murderbot's new allies have been up to, but there is a lot of speculative exploration and detailed descriptions of underground tunnels that I found less compelling than the relationship dynamics of the previous book. (Murderbot, on the other hand, would much prefer exploring creepy abandoned tunnels to talking about its feelings.) One of the things this series continues to do incredibly well, though, is take non-human intelligence seriously in a world where the humans mostly don't. It perfectly fills a gap between Star Wars, where neither the humans nor the story take non-human intelligences seriously (hence the creepy slavery vibes as soon as you start paying attention to droids), and the Culture, where both humans and the story do. The corporates (the bad guys in this series) treat non-human intelligences the way Star Wars treats droids. The good guys treat Murderbot mostly like a strange human, which is better but still wrong, and still don't notice the numerous other machine intelligences. But Wells, as the author, takes all of the non-human characters seriously, which means there are complex and fascinating relationships happening at a level of the story that the human characters are mostly unaware of. I love that Murderbot rarely bothers to explain; if the humans are too blinkered to notice, that's their problem. About halfway into the story, System Collapse hits its stride, not coincidentally at the point where Murderbot befriends some new computers. The rest of the book is great. This was not as good as Network Effect. There is a bit less competence porn at the start, and although that's for good in-story reasons I still missed it. Murderbot's redaction of things it doesn't want to talk about got a bit annoying before it finally resolved. And I was not sufficiently interested in this planet to want to spend two novels on it, at least without another major revelation that didn't come. But it's still a Murderbot novel, which means it has the best first-person narrative voice I've ever read, some great moments, and possibly the most compelling and varied presentation of computer intelligence in science fiction at the moment.
There was no feed ID, but AdaCol2 supplied the name Lucia and when I asked it for more info, the gender signifier bb (which didn t translate) and he/him pronouns. (I asked because the humans would bug me for the information; I was as indifferent to human gender as it was possible to be without being unconscious.)
This is not a series to read out of order, but if you have read this far, you will continue to be entertained. You don't need me to tell you this nearly everyone reviewing science fiction is saying it but this series is great and you should read it. Rating: 8 out of 10

19 January 2024

Russell Coker: 2.5Gbit Ethernet

I just decided to upgrade the core of my home network from 1Gbit to 2.5Gbit. I didn t really need to do this, it was only about 5 years ago that I upgrade from 100Mbit to 1Gbit. but it s cheap and seemed interesting. I decided to do it because a 2.5Gbit switch was listed as cheap on Ozbargain Computing [1], that was $40.94 delivered. If you are in Australia and like computers then Ozbargain is a site worth polling, every day there s interesting things at low prices. The seller of the switch is KeeplinkStore [2] who distinguished themselves by phoning me from China to inform me that I had ordered a switch with a UK plug for delivery to Australia and suggesting that I cancel the order and make a new order with an Australian plug. It wouldn t have been a big deal if I had received a UK plug as I ve got a collection of adaptors but it was still nice of them to make it convenient for me. The switch basically does what it s expected to do and has no fan so it s quiet. I got a single port 2.5Gbit PCIe card for $18.77 and a dual port card for $34.07. Those cards are a little expensive when compared to 1Gbit cards but very cheap when compared to the computers they are installed in. These cards use the Realtek RTL8125 chipset and work well. I got a USB-3 2.5Gbit device for $17.43. I deliberately didn t get USB-C because I still use laptops without USB-C and most of the laptops with USB-C only have a single USB-C port which is used for power. I don t plan to stop using my 100Mbit USB ethernet device because most of the time I don t need a lot of speed. But sometimes I do things like testing auto-install on laptops and then having something faster than Gigabit is good. This card worked at 1Gbit speed on a 1Gbit network when used with a system running Debian/Bookworm with kernel 6.1 and worked at 2.5Gbit speed when connected to my LicheePi RISC-V system running Linux 5.10, but it would only do 100Mbit on my laptop running Debian/Unstable with kernel 6.6 (Debian Bug #1061095) [3]. It s a little disappointing but not many people have such hardware so it probably doesn t get a lot of testing. For the moment I plan to just use a 1Gbit USB Ethernet device most of the time and if I really need the speed I ll just use an older kernel. I did some tests with wget and curl to see if I could get decent speeds. When using wget 1.21.3 on Debian/Bookworm I got transfer speeds of 103MB/s and 18.8s of system CPU time out of 23.6s of elapsed time. Curl on Debian/Bookworm did 203MB/s and took 10.7s of system CPU time out of 11.8s elapsed time. The difference is that curl was using 100KB read buffers and a mix of 12K and 4K write buffers while wget was using 8KB read buffers and 4KB write buffers. On Debian/Unstable wget 1.21.4 uses 64K read buffers and a mix of 4K and 60K write buffers and gets a speed of 208MB/s. As an experiment I changed the read buffer size for wget to 256K and that got the speed up to around 220MB/s but it was difficult to measure as the occasional packet loss slowed things down. The pattern of writing 4K and then writing the rest continued, it seemed related to fwrite() buffering. For anyone else who wants to experiment with the code, the wget code is simpler (due to less features) and the package builds a lot faster (due to fewer tests) so that s the one to work on. The client machine for these tests has a E5-2696 v3 CPU, this doesn t compare well to some of the recent AMD CPUs on single-core performance but is still a decently powerful system. Getting good performance at Gigabit speeds on an ARM or RISC-V system is probably going to be a lot harder than getting good performance at 2.5Gbit speeds on this system. In conclusion 2.5Gbit basically works apart from a problem with new kernels and a problem with the old version of wget. I expect that when Debian/Trixie is released (probably mid 2025) things will work well. For good transfer rates use wget version 1.21.4 or newer or use curl. As an aside I use a 1500byte MTU because I have some 100baseT systems on my LAN and the settings regarding TCP acceleration etc are all the defaults.

15 January 2024

Colin Watson: OpenUK New Year s Honours

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

30 December 2023

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

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

19 December 2023

Fran ois Marier: Filtering your own spam using SpamAssassin

I know that people rave about GMail's spam filtering, but it didn't work for me: I was seeing too many false positives. I personally prefer to see some false negatives (i.e. letting some spam through), but to reduce false positives as much as possible (and ideally have a way to tune this). Here's the local SpamAssassin setup I have put together over many years. In addition to the parts I describe here, I also turn off greylisting on my email provider (KolabNow) because I don't want to have to wait for up to 10 minutes for a "2FA" email to go through. This setup assumes that you download all of your emails to your local machine. I use fetchmail for this, though similar tools should work too.

Three tiers of emails The main reason my setup works for me, despite my receiving hundreds of spam messages every day, is that I split incoming emails into three tiers via procmail:
  1. not spam: delivered to inbox
  2. likely spam: quarantined in a soft_spam/ folder
  3. definitely spam: silently deleted
I only ever have to review the likely spam tier for false positives, which is on the order of 10-30 spam emails a day. I never even see the the hundreds that are silently deleted due to a very high score. This is implemented based on a threshold in my .procmailrc:
# Use spamassassin to check for spam
:0fw: .spamassassin.lock
  /usr/bin/spamassassin
# Throw away messages with a score of > 12.0
:0
* ^X-Spam-Level: \*\*\*\*\*\*\*\*\*\*\*\*
/dev/null
:0:
* ^X-Spam-Status: Yes
$HOME/Mail/soft_spam/
# Deliver all other messages
:0:
$ DEFAULT 
I also use the following ~/.muttrc configuration to easily report false negatives/positives and examine my likely spam folder via a shortcut in mutt:
unignore X-Spam-Level
unignore X-Spam-Status
macro index S "c=soft_spam/\n" "Switch to soft_spam"
# Tell mutt about SpamAssassin headers so that I can sort by spam score
spam "X-Spam-Status: (Yes No), (hits score)=(-?[0-9]+\.[0-9])" "%3"
folder-hook =soft_spam 'push ol'
folder-hook =spam 'push ou'
# <Esc>d = de-register as non-spam, register as spam, move to spam folder.
macro index \ed "<enter-command>unset wait_key\n<pipe-entry>spamassassin -r\n<enter-command>set wait_key\n<save-message>=spam\n" "report the message as spam"
# <Esc>u = unregister as spam, register as non-spam, move to inbox folder.
macro index \eu "<enter-command>unset wait_key\n<pipe-entry>spamassassin -k\n<enter-command>set wait_key\n<save-message>=inbox\n" "correct the false positive (this is not spam)"

Custom SpamAssassin rules In addition to the default ruleset that comes with SpamAssassin, I've also accrued a number of custom rules over the years. The first set comes from the (now defunct) SpamAssassin Rules Emporium. The second set is the one that backs bugs.debian.org and lists.debian.org. Note this second one includes archived copies of some of the SARE rules and so I only use some of the rules in the common/ directory. Finally, I wrote a few custom rules of my own based on specific kinds of emails I have seen slip through the cracks. I haven't written any of those in a long time and I suspect some of my rules are now obsolete. You may want to do your own testing before you copy these outright. In addition to rules to match more spam, I've also written a ruleset to remove false positives in French emails coming from many of the above custom rules. I also wrote a rule to get a bonus to any email that comes with a patch:
describe FM_PATCH   Includes a patch
body FM_PATCH   /\bdiff -pruN\b/
score FM_PATCH  -1.0
since it's not very common in spam emails :)

SpamAssassin settings When it comes to my system-wide SpamAssassin configuration in /etc/spamassassin/, I enable the following plugins:
loadplugin Mail::SpamAssassin::Plugin::AntiVirus
loadplugin Mail::SpamAssassin::Plugin::AskDNS
loadplugin Mail::SpamAssassin::Plugin::ASN
loadplugin Mail::SpamAssassin::Plugin::AutoLearnThreshold
loadplugin Mail::SpamAssassin::Plugin::Bayes
loadplugin Mail::SpamAssassin::Plugin::BodyEval
loadplugin Mail::SpamAssassin::Plugin::Check
loadplugin Mail::SpamAssassin::Plugin::DKIM
loadplugin Mail::SpamAssassin::Plugin::DNSEval
loadplugin Mail::SpamAssassin::Plugin::FreeMail
loadplugin Mail::SpamAssassin::Plugin::FromNameSpoof
loadplugin Mail::SpamAssassin::Plugin::HashBL
loadplugin Mail::SpamAssassin::Plugin::HeaderEval
loadplugin Mail::SpamAssassin::Plugin::HTMLEval
loadplugin Mail::SpamAssassin::Plugin::HTTPSMismatch
loadplugin Mail::SpamAssassin::Plugin::ImageInfo
loadplugin Mail::SpamAssassin::Plugin::MIMEEval
loadplugin Mail::SpamAssassin::Plugin::MIMEHeader
loadplugin Mail::SpamAssassin::Plugin::OLEVBMacro
loadplugin Mail::SpamAssassin::Plugin::PDFInfo
loadplugin Mail::SpamAssassin::Plugin::Phishing
loadplugin Mail::SpamAssassin::Plugin::Pyzor
loadplugin Mail::SpamAssassin::Plugin::Razor2
loadplugin Mail::SpamAssassin::Plugin::RelayEval
loadplugin Mail::SpamAssassin::Plugin::ReplaceTags
loadplugin Mail::SpamAssassin::Plugin::Rule2XSBody
loadplugin Mail::SpamAssassin::Plugin::SpamCop
loadplugin Mail::SpamAssassin::Plugin::TextCat
loadplugin Mail::SpamAssassin::Plugin::TxRep
loadplugin Mail::SpamAssassin::Plugin::URIDetail
loadplugin Mail::SpamAssassin::Plugin::URIEval
loadplugin Mail::SpamAssassin::Plugin::VBounce
loadplugin Mail::SpamAssassin::Plugin::WelcomeListSubject
loadplugin Mail::SpamAssassin::Plugin::WLBLEval
Some of these require extra helper packages or Perl libraries to be installed. See the comments in the relevant *.pre files. My ~/.spamassassin/user_prefs file contains the following configuration:
required_hits   5
ok_locales en fr
# Bayes options
score BAYES_00 -4.0
score BAYES_40 -0.5
score BAYES_60 1.0
score BAYES_80 2.7
score BAYES_95 4.0
score BAYES_99 6.0
bayes_auto_learn 1
bayes_ignore_header X-Miltered
bayes_ignore_header X-MIME-Autoconverted
bayes_ignore_header X-Evolution
bayes_ignore_header X-Virus-Scanned
bayes_ignore_header X-Forwarded-For
bayes_ignore_header X-Forwarded-By
bayes_ignore_header X-Scanned-By
bayes_ignore_header X-Spam-Level
bayes_ignore_header X-Spam-Status
as well as manual score reductions due to false positives, and manual score increases to help push certain types of spam emails over the 12.0 definitely spam threshold. Finally, I have the FuzzyOCR package installed since it has occasionally flagged some spam that other tools had missed. It is a little resource intensive though and so you may want to avoid this one if you are filtering spam for other people. As always, feel free to leave a comment if you do something else that works well and that's not included in my setup. This is a work-in-progress.

7 December 2023

Daniel Kahn Gillmor: New OpenPGP certificate for dkg, December 2023

dkg's New OpenPGP certificate in December 2023 In December of 2023, I'm moving to a new OpenPGP certificate. You might know my old OpenPGP certificate, which had an fingerprint of C29F8A0C01F35E34D816AA5CE092EB3A5CA10DBA. My new OpenPGP certificate has a fingerprint of: D477040C70C2156A5C298549BB7E9101495E6BF7. Both certificates have the same set of User IDs:
  • Daniel Kahn Gillmor
  • <dkg@debian.org>
  • <dkg@fifthhorseman.net>
You can find a version of this transition statement signed by both the old and new certificates at: https://dkg.fifthhorseman.net/2023-dkg-openpgp-transition.txt The new OpenPGP certificate is:
-----BEGIN PGP PUBLIC KEY BLOCK-----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=9Yc8
-----END PGP PUBLIC KEY BLOCK-----
When I have some reasonable number of certifications, i'll update the certificate associated with my e-mail addresses on https://keys.openpgp.org, in DANE, and in WKD. Until then, those lookups should continue to provide the old certificate.

27 November 2023

Andrew Cater: 20231123 - UEFI install on a Raspberry Pi 4 - step by step instructions to a modified d-i

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




21 November 2023

Mike Hommey: How I (kind of) killed Mercurial at Mozilla

Did you hear the news? Firefox development is moving from Mercurial to Git. While the decision is far from being mine, and I was barely involved in the small incremental changes that ultimately led to this decision, I feel I have to take at least some responsibility. And if you are one of those who would rather use Mercurial than Git, you may direct all your ire at me. But let's take a step back and review the past 25 years leading to this decision. You'll forgive me for skipping some details and any possible inaccuracies. This is already a long post, while I could have been more thorough, even I think that would have been too much. This is also not an official Mozilla position, only my personal perception and recollection as someone who was involved at times, but mostly an observer from a distance. From CVS to DVCS From its release in 1998, the Mozilla source code was kept in a CVS repository. If you're too young to know what CVS is, let's just say it's an old school version control system, with its set of problems. Back then, it was mostly ubiquitous in the Open Source world, as far as I remember. In the early 2000s, the Subversion version control system gained some traction, solving some of the problems that came with CVS. Incidentally, Subversion was created by Jim Blandy, who now works at Mozilla on completely unrelated matters. In the same period, the Linux kernel development moved from CVS to Bitkeeper, which was more suitable to the distributed nature of the Linux community. BitKeeper had its own problem, though: it was the opposite of Open Source, but for most pragmatic people, it wasn't a real concern because free access was provided. Until it became a problem: someone at OSDL developed an alternative client to BitKeeper, and licenses of BitKeeper were rescinded for OSDL members, including Linus Torvalds (they were even prohibited from purchasing one). Following this fiasco, in April 2005, two weeks from each other, both Git and Mercurial were born. The former was created by Linus Torvalds himself, while the latter was developed by Olivia Mackall, who was a Linux kernel developer back then. And because they both came out of the same community for the same needs, and the same shared experience with BitKeeper, they both were similar distributed version control systems. Interestingly enough, several other DVCSes existed: In this landscape, the major difference Git was making at the time was that it was blazing fast. Almost incredibly so, at least on Linux systems. That was less true on other platforms (especially Windows). It was a game-changer for handling large codebases in a smooth manner. Anyways, two years later, in 2007, Mozilla decided to move its source code not to Bzr, not to Git, not to Subversion (which, yes, was a contender), but to Mercurial. The decision "process" was laid down in two rather colorful blog posts. My memory is a bit fuzzy, but I don't recall that it was a particularly controversial choice. All of those DVCSes were still young, and there was no definite "winner" yet (GitHub hadn't even been founded). It made the most sense for Mozilla back then, mainly because the Git experience on Windows still wasn't there, and that mattered a lot for Mozilla, with its diverse platform support. As a contributor, I didn't think much of it, although to be fair, at the time, I was mostly consuming the source tarballs. Personal preferences Digging through my archives, I've unearthed a forgotten chapter: I did end up setting up both a Mercurial and a Git mirror of the Firefox source repository on alioth.debian.org. Alioth.debian.org was a FusionForge-based collaboration system for Debian developers, similar to SourceForge. It was the ancestor of salsa.debian.org. I used those mirrors for the Debian packaging of Firefox (cough cough Iceweasel). The Git mirror was created with hg-fast-export, and the Mercurial mirror was only a necessary step in the process. By that time, I had converted my Subversion repositories to Git, and switched off SVK. Incidentally, I started contributing to Git around that time as well. I apparently did this not too long after Mozilla switched to Mercurial. As a Linux user, I think I just wanted the speed that Mercurial was not providing. Not that Mercurial was that slow, but the difference between a couple seconds and a couple hundred milliseconds was a significant enough difference in user experience for me to prefer Git (and Firefox was not the only thing I was using version control for) Other people had also similarly created their own mirror, or with other tools. But none of them were "compatible": their commit hashes were different. Hg-git, used by the latter, was putting extra information in commit messages that would make the conversion differ, and hg-fast-export would just not be consistent with itself! My mirror is long gone, and those have not been updated in more than a decade. I did end up using Mercurial, when I got commit access to the Firefox source repository in April 2010. I still kept using Git for my Debian activities, but I now was also using Mercurial to push to the Mozilla servers. I joined Mozilla as a contractor a few months after that, and kept using Mercurial for a while, but as a, by then, long time Git user, it never really clicked for me. It turns out, the sentiment was shared by several at Mozilla. Git incursion In the early 2010s, GitHub was becoming ubiquitous, and the Git mindshare was getting large. Multiple projects at Mozilla were already entirely hosted on GitHub. As for the Firefox source code base, Mozilla back then was kind of a Wild West, and engineers being engineers, multiple people had been using Git, with their own inconvenient workflows involving a local Mercurial clone. The most popular set of scripts was moz-git-tools, to incorporate changes in a local Git repository into the local Mercurial copy, to then send to Mozilla servers. In terms of the number of people doing that, though, I don't think it was a lot of people, probably a few handfuls. On my end, I was still keeping up with Mercurial. I think at that time several engineers had their own unofficial Git mirrors on GitHub, and later on Ehsan Akhgari provided another mirror, with a twist: it also contained the full CVS history, which the canonical Mercurial repository didn't have. This was particularly interesting for engineers who needed to do some code archeology and couldn't get past the 2007 cutoff of the Mercurial repository. I think that mirror ultimately became the official-looking, but really unofficial, mozilla-central repository on GitHub. On a side note, a Mercurial repository containing the CVS history was also later set up, but that didn't lead to something officially supported on the Mercurial side. Some time around 2011~2012, I started to more seriously consider using Git for work myself, but wasn't satisfied with the workflows others had set up for themselves. I really didn't like the idea of wasting extra disk space keeping a Mercurial clone around while using a Git mirror. I wrote a Python script that would use Mercurial as a library to access a remote repository and produce a git-fast-import stream. That would allow the creation of a git repository without a local Mercurial clone. It worked quite well, but it was not able to incrementally update. Other, more complete tools existed already, some of which I mentioned above. But as time was passing and the size and depth of the Mercurial repository was growing, these tools were showing their limits and were too slow for my taste, especially for the initial clone. Boot to Git In the same time frame, Mozilla ventured in the Mobile OS sphere with Boot to Gecko, later known as Firefox OS. What does that have to do with version control? The needs of third party collaborators in the mobile space led to the creation of what is now the gecko-dev repository on GitHub. As I remember it, it was challenging to create, but once it was there, Git users could just clone it and have a working, up-to-date local copy of the Firefox source code and its history... which they could already have, but this was the first officially supported way of doing so. Coincidentally, Ehsan's unofficial mirror was having trouble (to the point of GitHub closing the repository) and was ultimately shut down in December 2013. You'll often find comments on the interwebs about how GitHub has become unreliable since the Microsoft acquisition. I can't really comment on that, but if you think GitHub is unreliable now, rest assured that it was worse in its beginning. And its sustainability as a platform also wasn't a given, being a rather new player. So on top of having this official mirror on GitHub, Mozilla also ventured in setting up its own Git server for greater control and reliability. But the canonical repository was still the Mercurial one, and while Git users now had a supported mirror to pull from, they still had to somehow interact with Mercurial repositories, most notably for the Try server. Git slowly creeping in Firefox build tooling Still in the same time frame, tooling around building Firefox was improving drastically. For obvious reasons, when version control integration was needed in the tooling, Mercurial support was always a no-brainer. The first explicit acknowledgement of a Git repository for the Firefox source code, other than the addition of the .gitignore file, was bug 774109. It added a script to install the prerequisites to build Firefox on macOS (still called OSX back then), and that would print a message inviting people to obtain a copy of the source code with either Mercurial or Git. That was a precursor to current bootstrap.py, from September 2012. Following that, as far as I can tell, the first real incursion of Git in the Firefox source tree tooling happened in bug 965120. A few days earlier, bug 952379 had added a mach clang-format command that would apply clang-format-diff to the output from hg diff. Obviously, running hg diff on a Git working tree didn't work, and bug 965120 was filed, and support for Git was added there. That was in January 2014. A year later, when the initial implementation of mach artifact was added (which ultimately led to artifact builds), Git users were an immediate thought. But while they were considered, it was not to support them, but to avoid actively breaking their workflows. Git support for mach artifact was eventually added 14 months later, in March 2016. From gecko-dev to git-cinnabar Let's step back a little here, back to the end of 2014. My user experience with Mercurial had reached a level of dissatisfaction that was enough for me to decide to take that script from a couple years prior and make it work for incremental updates. That meant finding a way to store enough information locally to be able to reconstruct whatever the incremental updates would be relying on (guess why other tools hid a local Mercurial clone under hood). I got something working rather quickly, and after talking to a few people about this side project at the Mozilla Portland All Hands and seeing their excitement, I published a git-remote-hg initial prototype on the last day of the All Hands. Within weeks, the prototype gained the ability to directly push to Mercurial repositories, and a couple months later, was renamed to git-cinnabar. At that point, as a Git user, instead of cloning the gecko-dev repository from GitHub and switching to a local Mercurial repository whenever you needed to push to a Mercurial repository (i.e. the aforementioned Try server, or, at the time, for reviews), you could just clone and push directly from/to Mercurial, all within Git. And it was fast too. You could get a full clone of mozilla-central in less than half an hour, when at the time, other similar tools would take more than 10 hours (needless to say, it's even worse now). Another couple months later (we're now at the end of April 2015), git-cinnabar became able to start off a local clone of the gecko-dev repository, rather than clone from scratch, which could be time consuming. But because git-cinnabar and the tool that was updating gecko-dev weren't producing the same commits, this setup was cumbersome and not really recommended. For instance, if you pushed something to mozilla-central with git-cinnabar from a gecko-dev clone, it would come back with a different commit hash in gecko-dev, and you'd have to deal with the divergence. Eventually, in April 2020, the scripts updating gecko-dev were switched to git-cinnabar, making the use of gecko-dev alongside git-cinnabar a more viable option. Ironically(?), the switch occurred to ease collaboration with KaiOS (you know, the mobile OS born from the ashes of Firefox OS). Well, okay, in all honesty, when the need of syncing in both directions between Git and Mercurial (we only had ever synced from Mercurial to Git) came up, I nudged Mozilla in the direction of git-cinnabar, which, in my (biased but still honest) opinion, was the more reliable option for two-way synchronization (we did have regular conversion problems with hg-git, nothing of the sort has happened since the switch). One Firefox repository to rule them all For reasons I don't know, Mozilla decided to use separate Mercurial repositories as "branches". With the switch to the rapid release process in 2011, that meant one repository for nightly (mozilla-central), one for aurora, one for beta, and one for release. And with the addition of Extended Support Releases in 2012, we now add a new ESR repository every year. Boot to Gecko also had its own branches, and so did Fennec (Firefox for Mobile, before Android). There are a lot of them. And then there are also integration branches, where developer's work lands before being merged in mozilla-central (or backed out if it breaks things), always leaving mozilla-central in a (hopefully) good state. Only one of them remains in use today, though. I can only suppose that the way Mercurial branches work was not deemed practical. It is worth noting, though, that Mercurial branches are used in some cases, to branch off a dot-release when the next major release process has already started, so it's not a matter of not knowing the feature exists or some such. In 2016, Gregory Szorc set up a new repository that would contain them all (or at least most of them), which eventually became what is now the mozilla-unified repository. This would e.g. simplify switching between branches when necessary. 7 years later, for some reason, the other "branches" still exist, but most developers are expected to be using mozilla-unified. Mozilla's CI also switched to using mozilla-unified as base repository. Honestly, I'm not sure why the separate repositories are still the main entry point for pushes, rather than going directly to mozilla-unified, but it probably comes down to switching being work, and not being a top priority. Also, it probably doesn't help that working with multiple heads in Mercurial, even (especially?) with bookmarks, can be a source of confusion. To give an example, if you aren't careful, and do a plain clone of the mozilla-unified repository, you may not end up on the latest mozilla-central changeset, but rather, e.g. one from beta, or some other branch, depending which one was last updated. Hosting is simple, right? Put your repository on a server, install hgweb or gitweb, and that's it? Maybe that works for... Mercurial itself, but that repository "only" has slightly over 50k changesets and less than 4k files. Mozilla-central has more than an order of magnitude more changesets (close to 700k) and two orders of magnitude more files (more than 700k if you count the deleted or moved files, 350k if you count the currently existing ones). And remember, there are a lot of "duplicates" of this repository. And I didn't even mention user repositories and project branches. Sure, it's a self-inflicted pain, and you'd think it could probably(?) be mitigated with shared repositories. But consider the simple case of two repositories: mozilla-central and autoland. You make autoland use mozilla-central as a shared repository. Now, you push something new to autoland, it's stored in the autoland datastore. Eventually, you merge to mozilla-central. Congratulations, it's now in both datastores, and you'd need to clean-up autoland if you wanted to avoid the duplication. Now, you'd think mozilla-unified would solve these issues, and it would... to some extent. Because that wouldn't cover user repositories and project branches briefly mentioned above, which in GitHub parlance would be considered as Forks. So you'd want a mega global datastore shared by all repositories, and repositories would need to only expose what they really contain. Does Mercurial support that? I don't think so (okay, I'll give you that: even if it doesn't, it could, but that's extra work). And since we're talking about a transition to Git, does Git support that? You may have read about how you can link to a commit from a fork and make-pretend that it comes from the main repository on GitHub? At least, it shows a warning, now. That's essentially the architectural reason why. So the actual answer is that Git doesn't support it out of the box, but GitHub has some backend magic to handle it somehow (and hopefully, other things like Gitea, Girocco, Gitlab, etc. have something similar). Now, to come back to the size of the repository. A repository is not a static file. It's a server with which you negotiate what you have against what it has that you want. Then the server bundles what you asked for based on what you said you have. Or in the opposite direction, you negotiate what you have that it doesn't, you send it, and the server incorporates what you sent it. Fortunately the latter is less frequent and requires authentication. But the former is more frequent and CPU intensive. Especially when pulling a large number of changesets, which, incidentally, cloning is. "But there is a solution for clones" you might say, which is true. That's clonebundles, which offload the CPU intensive part of cloning to a single job scheduled regularly. Guess who implemented it? Mozilla. But that only covers the cloning part. We actually had laid the ground to support offloading large incremental updates and split clones, but that never materialized. Even with all that, that still leaves you with a server that can display file contents, diffs, blames, provide zip archives of a revision, and more, all of which are CPU intensive in their own way. And these endpoints are regularly abused, and cause extra load to your servers, yes plural, because of course a single server won't handle the load for the number of users of your big repositories. And because your endpoints are abused, you have to close some of them. And I'm not mentioning the Try repository with its tens of thousands of heads, which brings its own sets of problems (and it would have even more heads if we didn't fake-merge them once in a while). Of course, all the above applies to Git (and it only gained support for something akin to clonebundles last year). So, when the Firefox OS project was stopped, there wasn't much motivation to continue supporting our own Git server, Mercurial still being the official point of entry, and git.mozilla.org was shut down in 2016. The growing difficulty of maintaining the status quo Slowly, but steadily in more recent years, as new tooling was added that needed some input from the source code manager, support for Git was more and more consistently added. But at the same time, as people left for other endeavors and weren't necessarily replaced, or more recently with layoffs, resources allocated to such tooling have been spread thin. Meanwhile, the repository growth didn't take a break, and the Try repository was becoming an increasing pain, with push times quite often exceeding 10 minutes. The ongoing work to move Try pushes to Lando will hide the problem under the rug, but the underlying problem will still exist (although the last version of Mercurial seems to have improved things). On the flip side, more and more people have been relying on Git for Firefox development, to my own surprise, as I didn't really push for that to happen. It just happened organically, by ways of git-cinnabar existing, providing a compelling experience to those who prefer Git, and, I guess, word of mouth. I was genuinely surprised when I recently heard the use of Git among moz-phab users had surpassed a third. I did, however, occasionally orient people who struggled with Mercurial and said they were more familiar with Git, towards git-cinnabar. I suspect there's a somewhat large number of people who never realized Git was a viable option. But that, on its own, can come with its own challenges: if you use git-cinnabar without being backed by gecko-dev, you'll have a hard time sharing your branches on GitHub, because you can't push to a fork of gecko-dev without pushing your entire local repository, as they have different commit histories. And switching to gecko-dev when you weren't already using it requires some extra work to rebase all your local branches from the old commit history to the new one. Clone times with git-cinnabar have also started to go a little out of hand in the past few years, but this was mitigated in a similar manner as with the Mercurial cloning problem: with static files that are refreshed regularly. Ironically, that made cloning with git-cinnabar faster than cloning with Mercurial. But generating those static files is increasingly time-consuming. As of writing, generating those for mozilla-unified takes close to 7 hours. I was predicting clone times over 10 hours "in 5 years" in a post from 4 years ago, I wasn't too far off. With exponential growth, it could still happen, although to be fair, CPUs have improved since. I will explore the performance aspect in a subsequent blog post, alongside the upcoming release of git-cinnabar 0.7.0-b1. I don't even want to check how long it now takes with hg-git or git-remote-hg (they were already taking more than a day when git-cinnabar was taking a couple hours). I suppose it's about time that I clarify that git-cinnabar has always been a side-project. It hasn't been part of my duties at Mozilla, and the extent to which Mozilla supports git-cinnabar is in the form of taskcluster workers on the community instance for both git-cinnabar CI and generating those clone bundles. Consequently, that makes the above git-cinnabar specific issues a Me problem, rather than a Mozilla problem. Taking the leap I can't talk for the people who made the proposal to move to Git, nor for the people who put a green light on it. But I can at least give my perspective. Developers have regularly asked why Mozilla was still using Mercurial, but I think it was the first time that a formal proposal was laid out. And it came from the Engineering Workflow team, responsible for issue tracking, code reviews, source control, build and more. It's easy to say "Mozilla should have chosen Git in the first place", but back in 2007, GitHub wasn't there, Bitbucket wasn't there, and all the available options were rather new (especially compared to the then 21 years-old CVS). I think Mozilla made the right choice, all things considered. Had they waited a couple years, the story might have been different. You might say that Mozilla stayed with Mercurial for so long because of the sunk cost fallacy. I don't think that's true either. But after the biggest Mercurial repository hosting service turned off Mercurial support, and the main contributor to Mercurial going their own way, it's hard to ignore that the landscape has evolved. And the problems that we regularly encounter with the Mercurial servers are not going to get any better as the repository continues to grow. As far as I know, all the Mercurial repositories bigger than Mozilla's are... not using Mercurial. Google has its own closed-source server, and Facebook has another of its own, and it's not really public either. With resources spread thin, I don't expect Mozilla to be able to continue supporting a Mercurial server indefinitely (although I guess Octobus could be contracted to give a hand, but is that sustainable?). Mozilla, being a champion of Open Source, also doesn't live in a silo. At some point, you have to meet your contributors where they are. And the Open Source world is now majoritarily using Git. I'm sure the vast majority of new hires at Mozilla in the past, say, 5 years, know Git and have had to learn Mercurial (although they arguably didn't need to). Even within Mozilla, with thousands(!) of repositories on GitHub, Firefox is now actually the exception rather than the norm. I should even actually say Desktop Firefox, because even Mobile Firefox lives on GitHub (although Fenix is moving back in together with Desktop Firefox, and the timing is such that that will probably happen before Firefox moves to Git). Heck, even Microsoft moved to Git! With a significant developer base already using Git thanks to git-cinnabar, and all the constraints and problems I mentioned previously, it actually seems natural that a transition (finally) happens. However, had git-cinnabar or something similarly viable not existed, I don't think Mozilla would be in a position to take this decision. On one hand, it probably wouldn't be in the current situation of having to support both Git and Mercurial in the tooling around Firefox, nor the resource constraints related to that. But on the other hand, it would be farther from supporting Git and being able to make the switch in order to address all the other problems. But... GitHub? I hope I made a compelling case that hosting is not as simple as it can seem, at the scale of the Firefox repository. It's also not Mozilla's main focus. Mozilla has enough on its plate with the migration of existing infrastructure that does rely on Mercurial to understandably not want to figure out the hosting part, especially with limited resources, and with the mixed experience hosting both Mercurial and git has been so far. After all, GitHub couldn't even display things like the contributors' graph on gecko-dev until recently, and hosting is literally their job! They still drop the ball on large blames (thankfully we have searchfox for those). Where does that leave us? Gitlab? For those criticizing GitHub for being proprietary, that's probably not open enough. Cloud Source Repositories? "But GitHub is Microsoft" is a complaint I've read a lot after the announcement. Do you think Google hosting would have appealed to these people? Bitbucket? I'm kind of surprised it wasn't in the list of providers that were considered, but I'm also kind of glad it wasn't (and I'll leave it at that). I think the only relatively big hosting provider that could have made the people criticizing the choice of GitHub happy is Codeberg, but I hadn't even heard of it before it was mentioned in response to Mozilla's announcement. But really, with literal thousands of Mozilla repositories already on GitHub, with literal tens of millions repositories on the platform overall, the pragmatic in me can't deny that it's an attractive option (and I can't stress enough that I wasn't remotely close to the room where the discussion about what choice to make happened). "But it's a slippery slope". I can see that being a real concern. LLVM also moved its repository to GitHub (from a (I think) self-hosted Subversion server), and ended up moving off Bugzilla and Phabricator to GitHub issues and PRs four years later. As an occasional contributor to LLVM, I hate this move. I hate the GitHub review UI with a passion. At least, right now, GitHub PRs are not a viable option for Mozilla, for their lack of support for security related PRs, and the more general shortcomings in the review UI. That doesn't mean things won't change in the future, but let's not get too far ahead of ourselves. The move to Git has just been announced, and the migration has not even begun yet. Just because Mozilla is moving the Firefox repository to GitHub doesn't mean it's locked in forever or that all the eggs are going to be thrown into one basket. If bridges need to be crossed in the future, we'll see then. So, what's next? The official announcement said we're not expecting the migration to really begin until six months from now. I'll swim against the current here, and say this: the earlier you can switch to git, the earlier you'll find out what works and what doesn't work for you, whether you already know Git or not. While there is not one unique workflow, here's what I would recommend anyone who wants to take the leap off Mercurial right now: As there is no one-size-fits-all workflow, I won't tell you how to organize yourself from there. I'll just say this: if you know the Mercurial sha1s of your previous local work, you can create branches for them with:
$ git branch <branch_name> $(git cinnabar hg2git <hg_sha1>)
At this point, you should have everything available on the Git side, and you can remove the .hg directory. Or move it into some empty directory somewhere else, just in case. But don't leave it here, it will only confuse the tooling. Artifact builds WILL be confused, though, and you'll have to ./mach configure before being able to do anything. You may also hit bug 1865299 if your working tree is older than this post. If you have any problem or question, you can ping me on #git-cinnabar or #git on Matrix. I'll put the instructions above somewhere on wiki.mozilla.org, and we can collaboratively iterate on them. Now, what the announcement didn't say is that the Git repository WILL NOT be gecko-dev, doesn't exist yet, and WON'T BE COMPATIBLE (trust me, it'll be for the better). Why did I make you do all the above, you ask? Because that won't be a problem. I'll have you covered, I promise. The upcoming release of git-cinnabar 0.7.0-b1 will have a way to smoothly switch between gecko-dev and the future repository (incidentally, that will also allow to switch from a pure git-cinnabar clone to a gecko-dev one, for the git-cinnabar users who have kept reading this far). What about git-cinnabar? With Mercurial going the way of the dodo at Mozilla, my own need for git-cinnabar will vanish. Legitimately, this begs the question whether it will still be maintained. I can't answer for sure. I don't have a crystal ball. However, the needs of the transition itself will motivate me to finish some long-standing things (like finalizing the support for pushing merges, which is currently behind an experimental flag) or implement some missing features (support for creating Mercurial branches). Git-cinnabar started as a Python script, it grew a sidekick implemented in C, which then incorporated some Rust, which then cannibalized the Python script and took its place. It is now close to 90% Rust, and 10% C (if you don't count the code from Git that is statically linked to it), and has sort of become my Rust playground (it's also, I must admit, a mess, because of its history, but it's getting better). So the day to day use with Mercurial is not my sole motivation to keep developing it. If it were, it would stay stagnant, because all the features I need are there, and the speed is not all that bad, although I know it could be better. Arguably, though, git-cinnabar has been relatively stagnant feature-wise, because all the features I need are there. So, no, I don't expect git-cinnabar to die along Mercurial use at Mozilla, but I can't really promise anything either. Final words That was a long post. But there was a lot of ground to cover. And I still skipped over a bunch of things. I hope I didn't bore you to death. If I did and you're still reading... what's wrong with you? ;) So this is the end of Mercurial at Mozilla. So long, and thanks for all the fish. But this is also the beginning of a transition that is not easy, and that will not be without hiccups, I'm sure. So fasten your seatbelts (plural), and welcome the change. To circle back to the clickbait title, did I really kill Mercurial at Mozilla? Of course not. But it's like I stumbled upon a few sparks and tossed a can of gasoline on them. I didn't start the fire, but I sure made it into a proper bonfire... and now it has turned into a wildfire. And who knows? 15 years from now, someone else might be looking back at how Mozilla picked Git at the wrong time, and that, had we waited a little longer, we would have picked some yet to come new horse. But hey, that's the tech cycle for you.

17 November 2023

Jonathan Dowland: HLedger, regex matches and field assignments

I've finally landed a patch/feature for HLedger I've been working on-and-off (mostly off) since around March. HLedger has a powerful CSV importer which you configure with a set of rules. Rules consist of conditional matchers (does field X in this CSV row match this regular expression?) and field assignments (set the resulting transaction's account to Y). motivating problem 1 Here's an example of one of my rules for handling credit card repayments. This rule is applied when I import a CSV for my current account, which pays the credit card:
if AMERICAN EXPRESS
    account2 liabilities:amex
This results in a ledger entry like the following
2023-10-31 AMERICAN EXPRESS
    assets:current           - 6.66
    liabilities:amex           6.66
My current account statements cover calendar months. My credit card period spans mid-month to mid-month. I pay it off by direct debit, which comes out after the credit card period, towards the very end of the calendar month. That transaction falls roughly halfway through the next credit card period. On my credit card statements, that repayment is "warped" to the start of the list of transactions, clearing the outstanding balance from the previous period. When I import my credit card data to HLedger, I want to compare the result against a PDF statement to make sure my ledger matches reality. The repayment "warping" makes this awkward, because it means the balance for roughly half the new transactions (those that fall before the real-date of the repayment) don't match up. motivating problem 2 I start new ledger files each year. I need to import the closing balances from the previous year to the next, which I do by exporting the final balance from the previous year in CSV and importing that into the new ledgers in the usual way. Between 2022 and 2023 I changed the scheme I use for account names so I need to translate between the old and the new in the opening balances. I couldn't think of a way of achieving this in the import rules (besides writing a bespoke rule for every possible old account name) so I abused another HLedger feature instead, HLedger aliases. For example I added this alias in my family ledger file for 2023
alias /^family:(.*)/ = \1
These are ugly and I'd prefer to get rid of them. regex match groups A common feature of regular expressions is defining match groups which can be referenced elsewhere, such as on the far-side of a substitution. I added match group support to HLedger's field assignments. addressing date warping Here's an updated version rule from the first motivating problem:
if AMERICAN EXPRESS
& %date (..)/(..)/(....)
    account2 liabilities:amex
    comment2 date:\3-\2-16
We now match on on extra date field, and surround the day/month/year components with parentheses to define match groups. We add a second field assignment too, setting the second posting's "comment" field to a string which, once the match groups are interpolated, instructs HLedger to do date warping (I wrote about this in date warping in HLedger) The new transaction looks like this:
2023-10-31 AMERICAN EXPRESS
    assets:current           - 6.66
    liabilities:amex           6.66 ; date:2023-10-16
getting rid of aliases In the second problem, I can strip off the unwanted account name prefixes at CSV import time, with rules like this
if %account2 ^family:(.*)$
    account2 \1
When! This stuff landed a week ago in early November, and is not yet in a Hledger release.

11 November 2023

Matthias Klumpp: AppStream 1.0 released!

Today, 12 years after the meeting where AppStream was first discussed and 11 years after I released a prototype implementation I am excited to announce AppStream 1.0!    Check it out on GitHub, or get the release tarball or read the documentation or release notes!

Some nostalgic memories I was not in the original AppStream meeting, since in 2011 I was extremely busy with finals preparations and ball organization in high school, but I still vividly remember sitting at school in the students lounge during a break and trying to catch the really choppy live stream from the meeting on my borrowed laptop (a futile exercise, I watched parts of the blurry recording later). I was extremely passionate about getting software deployment to work better on Linux and to improve the overall user experience, and spent many hours on the PackageKit IRC channel discussing things with many amazing people like Richard Hughes, Daniel Nicoletti, Sebastian Heinlein and others. At the time I was writing a software deployment tool called Listaller this was before Linux containers were a thing, and building it was very tough due to technical and personal limitations (I had just learned C!). Then in university, when I intended to recreate this tool, but for real and better this time as a new project called Limba, I needed a way to provide metadata for it, and AppStream fit right in! Meanwhile, Richard Hughes was tackling the UI side of things while creating GNOME Software and needed a solution as well. So I implemented a prototype and together we pretty much reshaped the early specification from the original meeting into what would become modern AppStream. Back then I saw AppStream as a necessary side-project for my actual project, and didn t even consider me as the maintainer of it for quite a while (I hadn t been at the meeting afterall). All those years ago I had no idea that ultimately I was developing AppStream not for Limba, but for a new thing that would show up later, with an even more modern design called Flatpak. I also had no idea how incredibly complex AppStream would become and how many features it would have and how much more maintenance work it would be and also not how ubiquitous it would become. The modern Linux desktop uses AppStream everywhere now, it is supported by all major distributions, used by Flatpak for metadata, used for firmware metadata via Richard s fwupd/LVFS, runs on every Steam Deck, can be found in cars and possibly many places I do not know yet.

What is new in 1.0?

API breaks The most important thing that s new with the 1.0 release is a bunch of incompatible changes. For the shared libraries, all deprecated API elements have been removed and a bunch of other changes have been made to improve the overall API and especially make it more binding-friendly. That doesn t mean that the API is completely new and nothing looks like before though, when possible the previous API design was kept and some changes that would have been too disruptive have not been made. Regardless of that, you will have to port your AppStream-using applications. For some larger ones I already submitted patches to build with both AppStream versions, the 0.16.x stable series as well as 1.0+. For the XML specification, some older compatibility for XML that had no or very few users has been removed as well. This affects for example release elements that reference downloadable data without an artifact block, which has not been supported for a while. For all of these, I checked to remove only things that had close to no users and that were a significant maintenance burden. So as a rule of thumb: If your XML validated with no warnings with the 0.16.x branch of AppStream, it will still be 100% valid with the 1.0 release. Another notable change is that the generated output of AppStream 1.0 will always be 1.0 compliant, you can not make it generate data for versions below that (this greatly reduced the maintenance cost of the project).

Developer element For a long time, you could set the developer name using the top-level developer_name tag. With AppStream 1.0, this is changed a bit. There is now a developer tag with a name child (that can be translated unless the translate="no" attribute is set on it). This allows future extensibility, and also allows to set a machine-readable id attribute in the developer element. This permits software centers to group software by developer easier, without having to use heuristics. If we decide to extend the developer information per-app in future, this is also now possible. Do not worry though the developer_name tag is also still read, so there is no high pressure to update. The old 0.16.x stable series also has this feature backported, so it can be available everywhere. Check out the developer tag specification for more details.

Scale factor for screenshots Screenshot images can now have a scale attribute, to indicate an (integer) scaling factor to apply. This feature was a breaking change and therefore we could not have it for the longest time, but it is now available. Please wait a bit for AppStream 1.0 to become deployed more widespread though, as using it with older AppStream versions may lead to issues in some cases. Check out the screenshots tag specification for more details.

Screenshot environments It is now possible to indicate the environment a screenshot was recorded in (GNOME, GNOME Dark, KDE Plasma, Windows, etc.) via an environment attribute on the respective screenshot tag. This was also a breaking change, so use it carefully for now! If projects want to, they can use this feature to supply dedicated screenshots depending on the environment the application page is displayed in. Check out the screenshots tag specification for more details.

References tag This is a feature more important for the scientific community and scientific applications. Using the references tag, you can associate the AppStream component with a DOI (Digital object identifier) or provide a link to a CFF file to provide citation information. It also allows to link to other scientific registries. Check out the references tag specification for more details.

Release tags Releases can have tags now, just like components. This is generally not a feature that I expect to be used much, but in certain instances it can become useful with a cooperating software center, for example to tag certain releases as long-term supported versions.

Multi-platform support Thanks to the interest and work of many volunteers, AppStream (mostly) runs on FreeBSD now, a NetBSD port exists, support for macOS was written and a Windows port is on its way! Thank you to everyone working on this

Better compatibility checks For a long time I thought that the AppStream library should just be a thin layer above the XML and that software centers should just implement a lot of the actual logic. This has not been the case for a while, but there was still a lot of complex AppStream features that were hard for software centers to implement and where it makes sense to have one implementation that projects can just use. The validation of component relations is one such thing. This was implemented in 0.16.x as well, but 1.0 vastly improves upon the compatibility checks, so you can now just run as_component_check_relations and retrieve a detailed list of whether the current component will run well on the system. Besides better API for software developers, the appstreamcli utility also has much improved support for relation checks, and I wrote about these changes in a previous post. Check it out! With these changes, I hope this feature will be used much more, and beyond just drivers and firmware.

So much more! The changelog for the 1.0 release is huge, and there are many papercuts resolved and changes made that I did not talk about here, like us using gi-docgen (instead of gtkdoc) now for nice API documentation, or the many improvements that went into better binding support, or better search, or just plain bugfixes.

Outlook I expect the transition to 1.0 to take a bit of time. AppStream has not broken its API for many, many years (since 2016), so a bunch of places need to be touched even if the changes themselves are minor in many cases. In hindsight, I should have also released 1.0 much sooner and it should not have become such a mega-release, but that was mainly due to time constraints. So, what s in it for the future? Contrary to what I thought, AppStream does not really seem to be done and fetature complete at a point, there is always something to improve, and people come up with new usecases all the time. So, expect more of the same in future: Bugfixes, validator improvements, documentation improvements, better tools and the occasional new feature. Onwards to 1.0.1!

30 September 2023

Russell Coker: Links September 2023

Interesting article in Wired about adversarial attacks on ML systems to get them to do things that they are explicitely programmed not to do such as describe how to make illegal drugs [1]. The most interesting part of this is that the attacks work on most GPT systems which is probably due to the similar data used to train them. Vice has an interesting article about the Danish Synthetic Party , a political partyled by an AI [2]. Citizens can vote for candidates who will try to get laws passed that match the AI generated goals, there is no option of voting for an AI character. The policies they are advocating for are designed to appeal to the 20% of Danes who don t vote. They are also trying to inspire similar parties in other countries. I think this has the potential to improve democracy. Vice reports that in 2021 a man tried to assasinate the Queen of England with inspiration from Star Wars and an AI chat bot [3]. While someone who wants to be a real-life Sith is probably going to end up doing something bad we still don t want to have chat bots encourage it. Bruce Schneier wrote an interesting article about milestones for AI involvement in the political process [4]. Sam Varghese wrote an interesting article about the allegations that India is following the example of Saudi Arabia and assasinating people in other countries who disagree with their government [5]. We need to stop this. Ian Jackson wrote an interesting blog post advocating that DKIM PRIVATE keys be rotated and PUBLISHED [6]. The idea is that if a hostile party gets access to the mailbox of someone who received private email from you then in the normal DKIM setup of keys never changing they can prove that the email is authentic when they leak it. While if you mail server publishes the old keys as Ian advocates then the hostile party can t prove that you sent the email in question as anyone could have forged a signature. Anything that involves publishing a private key gets an immediate negative reaction but I can t fault the logic here.

1 September 2023

Paul Wise: FLOSS Activities August 2023

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

Changes

Debugging
  • Investigated test failures after Debian pybuild distutils update

Issues

Review
  • Debian BTS usertags: changes for the month

Administration
  • Debian IRC: rescue an alternate channel and make it harder to join accidentally
  • Debian wiki: unblock IP addresses, approve accounts, update emails for accounts

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

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

27 August 2023

Steve McIntyre: We're back!

It's August Bank Holiday Weekend, we're in Cambridge. It must be the Debian UK OMGWTFBBQ!. We're about halfway through, and we've already polished off lots and lots of good food and beer. Lars is making pancakes as I write this, :-) We had an awesome game of Mao last night. People are having fun! Many thanks to a number of awesome friendly people for again sponsoring the important refreshments for the weekend. It's hungry/thirsty work celebrating like this!

21 August 2023

Melissa Wen: AMD Driver-specific Properties for Color Management on Linux (Part 1)

TL;DR: Color is a visual perception. Human eyes can detect a broader range of colors than any devices in the graphics chain. Since each device can generate, capture or reproduce a specific subset of colors and tones, color management controls color conversion and calibration across devices to ensure a more accurate and consistent color representation. We can expose a GPU-accelerated display color management pipeline to support this process and enhance results, and this is what we are doing on Linux to improve color management on Gamescope/SteamDeck. Even with the challenges of being external developers, we have been working on mapping AMD GPU color capabilities to the Linux kernel color management interface, which is a combination of DRM and AMD driver-specific color properties. This more extensive color management pipeline includes pre-defined Transfer Functions, 1-Dimensional LookUp Tables (1D LUTs), and 3D LUTs before and after the plane composition/blending.
The study of color is well-established and has been explored for many years. Color science and research findings have also guided technology innovations. As a result, color in Computer Graphics is a very complex topic that I m putting a lot of effort into becoming familiar with. I always find myself rereading all the materials I have collected about color space and operations since I started this journey (about one year ago). I also understand how hard it is to find consensus on some color subjects, as exemplified by all explanations around the 2015 online viral phenomenon of The Black and Blue Dress. Have you heard about it? What is the color of the dress for you? So, taking into account my skills with colors and building consensus, this blog post only focuses on GPU hardware capabilities to support color management :-D If you want to learn more about color concepts and color on Linux, you can find useful links at the end of this blog post.

Linux Kernel, show me the colors ;D DRM color management interface only exposes a small set of post-blending color properties. Proposals to enhance the DRM color API from different vendors have landed the subsystem mailing list over the last few years. On one hand, we got some suggestions to extend DRM post-blending/CRTC color API: DRM CRTC 3D LUT for R-Car (2020 version); DRM CRTC 3D LUT for Intel (draft - 2020); DRM CRTC 3D LUT for AMD by Igalia (v2 - 2023); DRM CRTC 3D LUT for R-Car (v2 - 2023). On the other hand, some proposals to extend DRM pre-blending/plane API: DRM plane colors for Intel (v2 - 2021); DRM plane API for AMD (v3 - 2021); DRM plane 3D LUT for AMD - 2021. Finally, Simon Ser sent the latest proposal in May 2023: Plane color pipeline KMS uAPI, from discussions in the 2023 Display/HDR Hackfest, and it is still under evaluation by the Linux Graphics community. All previous proposals seek a generic solution for expanding the API, but many seem to have stalled due to the uncertainty of matching well the hardware capabilities of all vendors. Meanwhile, the use of AMD color capabilities on Linux remained limited by the DRM interface, as the DCN 3.0 family color caps and mapping diagram below shows the Linux/DRM color interface without driver-specific color properties [*]: Bearing in mind that we need to know the variety of color pipelines in the subsystem to be clear about a generic solution, we decided to approach the issue from a different perspective and worked on enabling a set of Driver-Specific Color Properties for AMD Display Drivers. As a result, I recently sent another round of the AMD driver-specific color mgmt API. For those who have been following the AMD driver-specific proposal since the beginning (see [RFC][V1]), the main new features of the latest version [v2] are the addition of pre-blending Color Transformation Matrix (plane CTM) and the differentiation of Pre-defined Transfer Functions (TF) supported by color blocks. For those who just got here, I will recap this work in two blog posts. This one describes the current status of the AMD display driver in the Linux kernel/DRM subsystem and what changes with the driver-specific properties. In the next post, we go deeper to describe the features of each color block and provide a better picture of what is available in terms of color management for Linux.

The Linux kernel color management API and AMD hardware color capabilities Before discussing colors in the Linux kernel with AMD hardware, consider accessing the Linux kernel documentation (version 6.5.0-rc5). In the AMD Display documentation, you will find my previous work documenting AMD hardware color capabilities and the Color Management Properties. It describes how AMD Display Manager (DM) intermediates requests between the AMD Display Core component (DC) and the Linux/DRM kernel interface for color management features. It also describes the relevant function to call the AMD color module in building curves for content space transformations. A subsection also describes hardware color capabilities and how they evolve between versions. This subsection, DC Color Capabilities between DCN generations, is a good starting point to understand what we have been doing on the kernel side to provide a broader color management API with AMD driver-specific properties.

Why do we need more kernel color properties on Linux? Blending is the process of combining multiple planes (framebuffers abstraction) according to their mode settings. Before blending, we can manage the colors of various planes separately; after blending, we have combined those planes in only one output per CRTC. Color conversions after blending would be enough in a single-plane scenario or when dealing with planes in the same color space on the kernel side. Still, it cannot help to handle the blending of multiple planes with different color spaces and luminance levels. With plane color management properties, userspace can get a more accurate representation of colors to deal with the diversity of color profiles of devices in the graphics chain, bring a wide color gamut (WCG), convert High-Dynamic-Range (HDR) content to Standard-Dynamic-Range (SDR) content (and vice-versa). With a GPU-accelerated display color management pipeline, we can use hardware blocks for color conversions and color mapping and support advanced color management. The current DRM color management API enables us to perform some color conversions after blending, but there is no interface to calibrate input space by planes. Note that here I m not considering some workarounds in the AMD display manager mapping of DRM CRTC de-gamma and DRM CRTC CTM property to pre-blending DC de-gamma and gamut remap block, respectively. So, in more detail, it only exposes three post-blending features:
  • DRM CRTC de-gamma: used to convert the framebuffer s colors to linear gamma;
  • DRM CRTC CTM: used for color space conversion;
  • DRM CRTC gamma: used to convert colors to the gamma space of the connected screen.

AMD driver-specific color management interface We can compare the Linux color management API with and without the driver-specific color properties. From now, we denote driver-specific properties with the AMD prefix and generic properties with the DRM prefix. For visual comparison, I bring the DCN 3.0 family color caps and mapping diagram closer and present it here again: Mixing AMD driver-specific color properties with DRM generic color properties, we have a broader Linux color management system with the following features exposed by properties in the plane and CRTC interface, as summarized by this updated diagram: The blocks highlighted by red lines are the new properties in the driver-specific interface developed by me (Igalia) and Joshua (Valve). The red dashed lines are new links between API and AMD driver components implemented by us to connect the Linux/DRM interface to AMD hardware blocks, mapping components accordingly. In short, we have the following color management properties exposed by the DRM/AMD display driver:
  • Pre-blending - AMD Display Pipe and Plane (DPP):
    • AMD plane de-gamma: 1D LUT and pre-defined transfer functions; used to linearize the input space of a plane;
    • AMD plane CTM: 3x4 matrix; used to convert plane color space;
    • AMD plane shaper: 1D LUT and pre-defined transfer functions; used to delinearize and/or normalize colors before applying 3D LUT;
    • AMD plane 3D LUT: 17x17x17 size with 12 bit-depth; three dimensional lookup table used for advanced color mapping;
    • AMD plane blend/out gamma: 1D LUT and pre-defined transfer functions; used to linearize back the color space after 3D LUT for blending.
  • Post-blending - AMD Multiple Pipe/Plane Combined (MPC):
    • DRM CRTC de-gamma: 1D LUT (can t be set together with plane de-gamma);
    • DRM CRTC CTM: 3x3 matrix (remapped to post-blending matrix);
    • DRM CRTC gamma: 1D LUT + AMD CRTC gamma TF; added to take advantage of driver pre-defined transfer functions;
Note: You can find more about AMD display blocks in the Display Core Next (DCN) - Linux kernel documentation, provided by Rodrigo Siqueira (Linux/AMD display developer) in a 2021-documentation series. In the next post, I ll revisit this topic, explaining display and color blocks in detail.

How did we get a large set of color features from AMD display hardware? So, looking at AMD hardware color capabilities in the first diagram, we can see no post-blending (MPC) de-gamma block in any hardware families. We can also see that the AMD display driver maps CRTC/post-blending CTM to pre-blending (DPP) gamut_remap, but there is post-blending (MPC) gamut_remap (DRM CTM) from newer hardware versions that include SteamDeck hardware. You can find more details about hardware versions in the Linux kernel documentation/AMDGPU Product Information. I needed to rework these two mappings mentioned above to provide pre-blending/plane de-gamma and CTM for SteamDeck. I changed the DC mapping to detach stream gamut remap matrixes from the DPP gamut remap block. That means mapping AMD plane CTM directly to DPP/pre-blending gamut remap block and DRM CRTC CTM to MPC/post-blending gamut remap block. In this sense, I also limited plane CTM properties to those hardware versions with MPC/post-blending gamut_remap capabilities since older versions cannot support this feature without clashes with DRM CRTC CTM. Unfortunately, I couldn t prevent conflict between AMD plane de-gamma and DRM plane de-gamma since post-blending de-gamma isn t available in any AMD hardware versions until now. The fact is that a post-blending de-gamma makes little sense in the AMD color pipeline, where plane blending works better in a linear space, and there are enough color blocks to linearize content before blending. To deal with this conflict, the driver now rejects atomic commits if users try to set both AMD plane de-gamma and DRM CRTC de-gamma simultaneously. Finally, we had no other clashes when enabling other AMD driver-specific color properties for our use case, Gamescope/SteamDeck. Our main work for the remaining properties was understanding the data flow of each property, the hardware capabilities and limitations, and how to shape the data for programming the registers - AMD color block capabilities (and limitations) are the topics of the next blog post. Besides that, we fixed some driver bugs along the way since it was the first Linux use case for most of the new color properties, and some behaviors are only exposed when exercising the engine. Take a look at the Gamescope/Steam Deck Color Pipeline[**], and see how Gamescope uses the new API to manage color space conversions and calibration (please click on the image for a better view): In the next blog post, I ll describe the implementation and technical details of each pre- and post-blending color block/property on the AMD display driver. * Thank Harry Wentland for helping with diagrams, color concepts and AMD capabilities. ** Thank Joshua Ashton for providing and explaining Gamescope/Steam Deck color pipeline. *** Thanks to the Linux Graphics community - explicitly Harry, Joshua, Pekka, Simon, Sebastian, Siqueira, Alex H. and Ville - to all the learning during this Linux DRM/AMD color journey. Also, Carlos and Tomas for organizing the 2023 Display/HDR Hackfest where we have a great and immersive opportunity to discuss Color & HDR on Linux.

Russ Allbery: Review: Some Desperate Glory

Review: Some Desperate Glory, by Emily Tesh
Publisher: Tordotcom
Copyright: 2023
ISBN: 1-250-83499-6
Format: Kindle
Pages: 438
Some Desperate Glory is a far-future space... opera? That's probably the right genre classification given the setting, but this book is much more intense and character-focused than most space opera. It is Emily Tesh's first novel, although she has two previous novellas that were published as books. The alien majo and their nearly all-powerful Wisdom have won the war by destroying Earth with an antimatter bomb. The remnants of humanity were absorbed into the sprawling majo civilization. Gaea Station is the lone exception: a marginally viable station deep in space, formed from a lifeless rocky planetoid and the coupled hulks of the last four human dreadnoughts. Gaea Station survives on military discipline, ruthless use of every available resource, and constant training, raising new generations of soldiers for the war that it refuses to let end. While Earth's children live, the enemy shall fear us. Kyr is a warbreed, one of a genetically engineered line of soldiers that, following an accident, Gaea Station has lost the ability to make except the old-fashioned way. Among the Sparrows, her mess group, she is the best at the simulated combat exercises they use for training. She may be the best of her age cohort except her twin Magnus. As this novel opens, she and the rest of the Sparrows are about to get their adult assignments. Kyr is absolutely focused on living up to her potential and the attention of her uncle Jole, the leader of the station. Kyr's future will look nothing like what she expects. This book was so good, and I despair of explaining why it was so good without unforgivable spoilers. I can tell you a few things about it, but be warned that I'll be reduced to helpless gestures and telling you to just go read it. It's been a very long time since I was this surprised by a novel, possibly since I read Code Name: Verity for the first time. Some Desperate Glory follows Kyr in close third-person throughout the book, which makes the start of this book daring. If you're getting a fascist vibe from the setup, you're not wrong, and this is intentional on Tesh's part. But Kyr is a true believer at the start of the book, so the first quarter has a protagonist who is sometimes nasty and cruel and who makes some frustratingly bad decisions. Stay with it, though; Tesh knows exactly what she's doing. This is a coming of age story, in a way. Kyr has a lot to learn and a lot to process, and Some Desperate Glory is about that process. But by the middle of part three, halfway through the book, I had absolutely no idea where Tesh was going with the story. She then pulled the rug out from under me, in the best way, at least twice more. Part five of this book is an absolute triumph, the payoff for everything that's happened over the course of the novel, and there is no way I could have predicted it in advance. It was deeply satisfying in that way where I felt like I learned some things along with the characters, and where the characters find a better ending than I could possibly have worked out myself. Tesh does use some world-building trickery, which is at its most complicated in part four. That was the one place where I can point to a few chapters where I thought the world-building got a bit too convenient in order to enable the plot. But it also allows for some truly incredible character work. I can't describe that in detail because it would be a major spoiler, but it's one of my favorite tropes in fiction and Tesh pulls it off beautifully. The character growth and interaction in this book is just so good: deep and complicated and nuanced and thoughtful in a way that revises reader impressions of earlier chapters. The other great thing about this book is that for a 400+ page novel, it moves right along. Both plot and character development is beautifully paced with only a few lulls. Tesh also doesn't belabor conversations. This is a book that provides just the right amount of context for the reader to fully understand what's going on, and then trusts the reader to be following along and moves straight to the next twist. That makes it propulsively readable. I had so much trouble putting this book down at any time during the second half. I can't give any specifics, again because of spoilers, but this is not just a character story. Some Desperate Glory has strong opinions on how to ethically approach the world, and those ethics are at the center of the plot. Unlike a lot of books with a moral stance, though, this novel shows the difficulty of the work of deriving that moral stance. I have rarely read a book that more perfectly captures the interior experience of changing one's mind with all of its emotional difficulty and internal resistance. Tesh provides all the payoff I was looking for as a reader, but she never makes it easy or gratuitous (with the arguable exception of one moment at the very end of the book that I think some people will dislike but that I personally needed). This is truly great stuff, probably the best science fiction novel that I've read in several years. Since I read it (I'm late on reviews again), I've pushed it on several other people, and I've not had a miss yet. The subject matter is pretty heavy, and this book also uses several tropes that I personally adore and am therefore incapable of being objective about, but with those caveats, this gets my highest possible recommendation. Some Desperate Glory is a complete story in one novel with a definite end, although I love these characters so much that I'd happily read their further adventures, even if those are thematically unnecessary. Content warnings: Uh, a lot. Genocide, suicide, sexual assault, racism, sexism, homophobia, misgendering, and torture, and I'm probably forgetting a few things. Tesh doesn't linger on these long, but most of them are on-screen. You may have to brace yourself for this one. Rating: 10 out of 10

9 August 2023

Antoine Beaupr : OpenPGP key transition

This is a short announcement to say that I have changed my main OpenPGP key. A signed statement is available with the cryptographic details but, in short, the reason is that I stopped using my old YubiKey NEO that I have worn on my keyring since 2015. I now have a YubiKey 5 which supports ED25519 which features much shorter keys and faster decryption. It allowed me to move all my secret subkeys on the key (including encryption keys) while retaining reasonable performance. I have written extensive documentation on how to do that OpenPGP key rotation and also YubiKey OpenPGP operations.

Warning on storing encryption keys on a YubiKey People wishing to move their private encryption keys to such a security token should be very careful as there are special precautions to take for disaster recovery. I am toying with the idea of writing an article specifically about disaster recovery for secrets and backups, dealing specifically with cases of death or disabilities.

Autocrypt changes One nice change is the impact on Autocrypt headers, which are considerably shorter. Before, the header didn't even fit on a single line in an email, it overflowed to five lines:
Autocrypt: addr=anarcat@torproject.org; prefer-encrypt=nopreference;
 keydata=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
 S60bWyLH4QnGxNaOoQvuAXiCYV4amKl7hSuDVZEn/9etDgm/UhGn2KS3yg0XFsqI7V/3RopHiDT+k7+zpAKd3st2V74w6ht+EFp2Gj0sNTBoCdbmIkRhiLyH9S4B+0Z5dUCUEopGIKKOSbQwyD5jILXEi7VTZhN0CrwIcCuqNo7OXI6e8gJd8McymqK4JrVoCipJbLzyOLxZMxGz8Ki0b9O844/DTzwcYcg9I1qogCsGmZfgVze2XtGxY+9zwSpeCLeef6QOPQ0uxsEYSfVgS+onCesSRCgwAPmppPiva+UlGuIMun87gPpQpV2fqFg/V8zBxRvs6YTGcfcQjfMoBHmZTGb+jk1//QAgnXMO7fGG38YH7iQSSzkmodrH2s27ZKgUTHVxpBL85ptftuRqbR7MzIKXZsKdA88kjIKKXwMmez9L1VbJkM4k+1Kzc5KdVydwi+ujpNegF6ZU8KDNFiN9TbDOlRxK5R+AjwdS8ZOIa4nci77KbNF9OZuO3l/FZwiKp8IFJ1nK7uiKUjmCukL0od/6X2rJtAzJmO5Co93ZVrd5r48oqUvjklzzsBNBFmeC3oBCADEV28RKzbv3dEbOocOsJQWr1R0EHUcbS270CrQZfb9VCZWkFlQ/1ypqFFQSjmmUGbNX2CG5mivVsW6Vgm7gg8HEnVCqzL02BPY4OmylskYMFI5Bra2wRNNQBgjg39L9XU4866q3BQzJp3r0fLRVH8gHM54Jf0FVmTyHotR/Xiw5YavNy2qaQXesqqUv8HBIha0rFblbuYI/cFwOtJ47gu0QmgrU0ytDjlnmDNx4rfsNylwTIHS0Oc7Pezp7MzLmZxnTM9b5VMprAXnQr4rewXCOUKBSto+j4rD5/77DzXw96bbueNruaupb2Iy2OHXNGkB0vKFD3xHsXE2x75NBovtABEBAAHCwqwEGAEIACAWIQSNyQHOZBRsBIrVD7t5IVJSe3WSHgUCWZ4LegIbAgFACRB5IV
 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
 YG7YEobMjX0CThKe6AV2118XNzRBw/S2IO1LWnL5qaGYPZONUa9Pj0OaErdKIk/V1wge8Zoav2fQPautBcRLW5VA33PH1ggoqKQ4ES1hc9HC6SYKzTCGixu97mu/vjOa8DYgM+33TosLyNy+bCzw62zJkMf89X0tTSdaJSj5Op0SrRvfgjbC2YpJOnXxHr9qaXFbBZQhLjemZi6zRzUNeJ6A3Nzs+gIc4H7s/bYBtcd4ugPEhDeCGffdS3TppH9PnvRXfoa5zj5bsKFgjqjWolCyAmEvd15tXz5yNXtvrpgDhjF5ozPiNp/1EeWX4DxbH2i17drVu4fXwauFZ6lcsAcJxnvCA28RlQlmEQu/gFOx1axVXf6GIuXnQSjQN6qJbByUYrdc/cFCxPO2/lGuUxnufN9Tvb51Qh54laPgGLrlD2huQeSD9Sxa0MNUjNY0qLqaReT99Ygb2LPYGSLoFVx9iZz6sZNt07LqCx9qNgsJwsdmwYsNpMuFbc7nkWjtlEqzsXZHTvYN654p43S+hcAhmmOzQZcew6h71fAJLciiqsPBnCEdgCGFAWhZZdPkMA==
After the change, the entire key fits on a single line, neat!
Autocrypt: addr=anarcat@torproject.org; prefer-encrypt=nopreference;
 keydata=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
Note that I have implemented my own kind of ridiculous Autocrypt support for the Notmuch Emacs email client I use, see this elisp code. To import keys, I pipe the message into this script which is basically just:
sq autocrypt decode   gpg --import
... thanks to Sequoia best-of-class Autocrypt support.

Note on OpenPGP usage While some have claimed OpenPGP's death, I believe those are overstated. Maybe it's just me, but I still use OpenPGP for my password management, to authenticate users and messages, and it's the interface to my YubiKey for authenticating with SSH servers. I understand people feel that OpenPGP is possibly insecure, counter-intuitive and full of problems, but I think most of those problems should instead be attributed to its current flagship implementation, GnuPG. I have tried to work with GnuPG for years, and it keeps surprising me with evilness and oddities. I have high hopes that the Sequoia project can bring some sanity into this space, and I also hope that RFC4880bis can eventually get somewhere so we have a more solid specification with more robust crypto. It's kind of a shame that this has dragged on for so long, but Update: there's a separate draft called openpgp-crypto-refresh that might actually be adopted as the "OpenPGP RFC" soon! And it doesn't keep real work from happening in Sequoia and other implementations. Thunderbird rewrote their OpenPGP implementation with RNP (which was, granted, a bumpy road because it lost compatibility with GnuPG) and Sequoia now has a certificate store with trust management (but still no secret storage), preliminary OpenPGP card support and even a basic GnuPG compatibility layer. I'm also curious to try out the OpenPGP CA capabilities. So maybe it's just because I'm becoming an old fart that doesn't want to change tools, but so far I haven't seen a good incentive in switching away from OpenPGP, and haven't found a good set of tools that completely replace it. Maybe OpenSSH's keys and CA can eventually replace it, but I suspect they will end up rebuilding most of OpenPGP anyway, just more slowly. If they do, let's hope they avoid the mistakes our community has done in the past at least...

26 July 2023

Valhalla's Things: Elastic Neck Top

Posted on July 26, 2023
A woman wearing a top in white fabric with thin blue lines and two groups of blue lozenges near the hems. It has a square neck gathered by a yellow elastic, the blue lines are horizontal on the wide sleeves and vertical, and more spaced, on the body. Since some time I ve been thinking about making myself a top or a dress with a wide gathered neckline that can be work at different widths, including off-the-shoulders. A few years ago I ve been gifted a cut of nice, thin white fabric with a print of lines and lozenges that isn t uniform along the fabric, but looks like it was designed for some specific garment, and it was waiting in my stash for a suitable pattern. And a few days ago, during a Sunday lunch, there was an off-hand mention of a dress from the late 1970s which had an elastic in the neckline, so that it could be optionally worn off-the-shoulders. And something snapped in place. I had plans for that afternoon, but they were scrapped, and I started to draw, measure, cut rectangles of fabric, pin and measure again, cut more fabric. The main pieces of the top laid flat: a big rectangle for the body,
two rectangular tubes for the sleeves laid so that they meet the body just at the corners, and a triangle (a square gusset folded on the diagonal) joins them to the body.
I decided on a pattern made of rectangles to be able to use as much fabric as possible, with the size of each rectangle based mostly on the various sections on the print of the fabric. I ve made the typical sleeves from a rectangle and a square gusset, and then attached them to the body just from the gusset to keep the neckline wide and low. The worn top shown from the side back: there is a strip of vertical lines spaced closer together like on the sleeves, and it continues to the bottom rather than ending with a strip of lozenges. The part of the fabric with large vertical stripes had two different widths: I could have made the back narrower, but I decided to just keep a strip with narrower lines to one side. The fabric also didn t have a full second strip of lozenges, so I had to hem it halfway through it. Closeup of the center front and center back of the neckline casing, showing the matched lines. The casing for the elastic was pieced from various scraps, but at least I was able to match the lines on the center front and back, even if they are different. Not that it matters a lot, since it s all hidden in the gathering, but I would have known. And since I was working on something definitely modern, even if made out of squares and rectangles, of course I decided to hand-sew everything, mostly to be able to use quite small sewing allowances, since the fabric was pretty thin. In my stash I had a piece of swimsuit elastic that feels nice, looks nice and makes a knot that doesn t slip, so I used it. It s a perfect match, except for the neon yellow colour, which I do like, but maybe is a bit too high visibility? I will see if the haberdasher has the same elastic in dark blue, but right now this will do. It was a quick project anyway: by the end of the working week the top was finished; I think that on a sewing machine it would be easy to make it in a day. the top worn with the neckline pulled down to leave the shoulders bare. And it can be worn off the shoulders! Which is something I will probably never do in public (and definitely not outdoors), but now if I wanted I could! :D As usual, the pattern (for what pattern there is) and instructions are on my pattern website under a #FreeSoftWear license, and I ve also added to the site a tip on how I use electrician fish tape to thread things through long casings

10 July 2023

Shirish Agarwal: PLIO, Mum, Debconf, Pressure Cooker, RISC-V,

PLIO I have been looking for an image viewer that can view images via modification date by default. The newer, the better. Alas, most of the image viewers do not do that. Even feh somehow fails. What I need is default listing of images as thumbnails by modification date. I put it up on Unix Stackexchange couple of years ago. Somebody shared ristretto but that just gives listing and doesn t give the way I want it. To be more illustrative, maybe this may serve as a guide to what I mean.
There is an RFP for it. While playing with it, I also discovered another benefit of the viewer, a sort of side-benefit, it tells you if any images have gone corrupt or whatever and you get that info. on the CLI so you can try viewing that image with the path using another viewer or viewers before deleting them. One of the issues is there doesn t seem to be a magnify option by default. While the documentation says use the ^ key to maximize it, it doesn t maximize. Took me a while to find it as that isn t a key that I use most of the time. Ironically, that is the key used on the mobile quite a bit. Anyways, so that needs to be fixed. Sadly, it doesn t have creation date or modification date sort, although the documentation does say it does (at least the modification date) but it doesn t show at my end. I also got Warning: UNKNOWN command detected! but that doesn t tell me enough as to what the issue is. Hopefully the developer will fix the issues and it will become part of Debian as many such projects are. Compiling was dead easy even with gcc-12 once I got freeimage-dev.

Mum s first death anniversary I do not know where the year went by or how. The day went in a sort of suspended animation. The only thing I did was eat and sleep that day, didn t feel like doing anything. Old memories, even dreams of fighting with her only to realize in the dream itself it s fake, she isn t there anymore  Something that can never be fixed

Debconf Kochi I should have shared it few days ago but somehow slipped my mind. While it s too late for most people to ask for bursary for Debconf Kochi, if you are anywhere near Kochi in the month of September between the dates. September 3 to September 17 nearby Infopark, Kochi you could walk in and talk to people. This would be for people who either have an interest in free software, FOSS or Debian specific. For those who may not know, while Debian is a Linux Distribution having ports to other kernels as well as well as hardware. While I may not be able to provide the list of all the various flavors as well as hardware, can say it is quite a bit. For e.g. there is a port to RISC-V that was done few years back (2018). Why that is needed will be shared below. There is always something new to look forward in a Debconf.

Pressure Cooker and Potatoes This was asked to me in the last Debconf (2016) by few people. So as people are coming to India, it probably is a good time to sort of reignite the topic :). So a Pressure Cooker boils your veggies and whatnot while still preserving the nutrients. While there are quite a number of brands I would suggest either Prestige or Hawkins, I have had good experience with both. There are also some new pressure cookers that have come that are somewhat in the design of the Thai Wok. So if that is something that you are either comfortable with or looking for, you could look at that. One of the things that you have to be sort of aware of and be most particular is the pressure safety valve. Just putting up pressure cooker safety valve in your favorite search-engine should show you different makes and whatnot. While they are relatively cheap, you need to see it is not cracked, used or whatever. The other thing is the Pressure Cooker whistle as well. The easiest thing to cook are mashed potatoes in a pressure cooker. A pressure Cooker comes in Litres, from 1 Ltr. to 20 Ltr. The larger ones are obviously for hotels or whatnot. General rule of using Pressure cooker is have water 1/4th, whatever vegetable or non-veg you want to boil 1/2 and let the remaining part for the steam. Now the easiest thing to do is have wash the potatoes and put 1/4th water of the pressure cooker. Then put 1/2 or less or little bit more of the veggies, in this instance just Potatoes. You can put salt to or that can be done later. The taste will be different. Also, there are various salts so won t really go into it as spices is a rabbit hole. Anyways, after making sure that there is enough space for the steam to be built, Put the handle on the cooker and basically wait for 5-10 minutes for the pressure to be built. You will hear a whistling sound, wait for around 5 minutes or a bit more (depends on many factors, kind of potatoes, weather etc.) and then just let it cool off naturally. After 5-10 minutes or a bit more, the pressure will be off. Your mashed potatoes are ready for either consumption or for further processing. I am assuming gas, induction cooking will have its own temperature, have no idea about it, hence not sharing that. Pressure Cooker, first put on the heaviest settings, once it starts to whistle, put it on medium for 5-10 minutes and then let it cool off. The first time I had tried that, I burned the cooker. You understand things via trial and error.

Poha recipe This is a nice low-cost healthy and fulfilling breakfast called Poha that can be made anytime and requires at the most 10-15 minutes to prepare with minimal fuss. The main ingredient is Poha or flattened rice. So how is it prepared. I won t go into the details of quantity as that is upto how hungry people are. There are various kinds of flattened rice available in the market, what you are looking for is called thick Poha or zhad Poha (in Marathi). The first step is the trickiest. What do you want to do is put water on Poha but not to let it be soggy. There is an accessory similar to tea filter but forgot the name, it basically drains all the extra moisture and you want Poha to be a bit fluffy and not soggy. The Poha should breathe for about 5 minutes before being cooked. To cook, use a heavy bottomed skillet, put some oil in it, depends on what oil you like, again lot of variations, you can use ground nut or whatever oil you prefer. Then use single mustard seeds to check temperature of the oil. Once the mustard seeds starts to pop, it means it s ready for things. So put mustard seeds in, finely chopped onion, finely chopped coriander leaves, a little bit of lemon juice, if you want potatoes, then potatoes too. Be aware that Potatoes will soak oil like anything, so if you are going to have potatoes than the oil should be a bit more. Some people love curry leaves, others don t. I like them quite a bit, it gives a slightly different taste. So the order is
  1. Oil
  2. Mustard seeds (1-2 teaspoon)
  3. Curry leaves 5-10
  4. Onion (2-3 medium onions finely chopped, onion can also be used as garnish.)
  5. Potatoes (2-3 medium ones, mashed)
  6. Small green chillies or 1-2 Red chillies (if you want)
  7. Coriander Leaves (one bunch finely chopped)
  8. Peanuts (half a glass)
Make sure that you are stirring them quite a bit. On a good warm skillet, this should hardly take 5 minutes. Once the onions are slighly brown, you are ready to put Poha in. So put the poha, add turmeric, salt, and sugar. Again depends on number of people. If I made for myself and mum, usually did 1 teaspoon of salt, not even one fourth of turmeric, just a hint, it is for the color, 1 to 2 teapoons of sugar and mix them all well at medium flame. Poha used to be two or three glasses. If you don t want potato, you can fry them a bit separately and garnish with it, along with coriander, coconut and whatnot. In Kerala, there is possibility that people might have it one day or all days. It serves as a snack at anytime, breakfast, lunch, tea time or even dinner if people don t want to be heavy. The first few times I did, I did manage to do everything wrong. So, if things go wrong, let it be. After a while, you will find your own place. And again, this is just one way, I m sure this can be made as elaborate a meal as you want. This is just something you can do if you don t want noodles or are bored with it. The timing is similar. While I don t claim to be an expert in cooking in anyway or form, if people have questions feel free to ask. If you are single or two people, 2 Ltr. Pressure cooker is enough for most Indians, Westerners may take a slightly bit larger Pressure Cooker, maybe a 3 Ltr. one may be good for you. Happy Cooking and Experimenting  I have had the pleasure to have Poha in many ways. One of my favorite ones is when people have actually put tadka on top of Poha. You do everything else but in a slight reverse order. The tadka has all the spices mixed and is concentrated and is put on top of Poha and then mixed. Done right, it tastes out of this world. For those who might not have had the Indian culinary experience, most of which is actually borrowed from the Mughals, you are in for a treat. One of the other things I would suggest to people is to ask people where there can get five types of rice. This is a specialty of South India and a sort of street food. I know where you can get it Hyderabad, Bangalore, Chennai but not in Kerala, although am dead sure there is, just somehow have missed it. If asked, am sure the Kerala team should be able to guide. That s all for now, feeling hungry, having dinner as have been sharing about cooking.

RISC-V There has been lot of conversations about how India could be in the microprocesor spacee. The x86 and x86-64 is all tied up in Intel and AMD so that s a no go area. Let me elaborate a bit why I say that. While most of the people know that IBM was the first producers of transistors as well as microprocessors. Coincidentally, AMD and Intel story are similar in some aspects but not in others. For a long time Intel was a market leader and by hook or crook it remained a market leader. One of the more interesting companies in the 1980s was Cyrix which sold lot of low-end microprocessors. A lot of that technology also went into Via which became a sort of spiritual successor of Cyrix. It is because of Cyrix and Via that Intel was forced to launch the Celeron model of microprocessors.

Lawsuits, European Regulation For those who have been there in the 1990s may have heard the term Wintel that basically meant Microsoft Windows and Intel and they had a sort of monopoly power. While the Americans were sorta ok with it, the Europeans were not and time and time again they forced both Microsoft as well as Intel to provide alternatives. The pushback from the regulators was so great that Intel funded AMD to remain solvent for few years. The successes that we see today from AMD is Lisa Su s but there is a whole lot of history as well as bad blood between the two companies. Lot of lawsuits and whatnot. Lot of cross-licensing agreements between them as well. So for any new country it would need lot of cash just for licensing all the patents there are and it s just not feasible for any newcomer to come in this market as they would have to fork the cash for the design apart from manufacturing fab.

ARM Most of the mobiles today sport an ARM processor. At one time it meant Advanced RISC Machines but now goes by Arm Ltd. Arm itself licenses its designs and while there are lot of customers, you are depending on ARM and they can change any of the conditions anytime they want. You are also hoping that ARM does not steal your design or do anything else with it. And while people trust ARM, it is still a risk if you are a company.

RISC and Shakti There is not much to say about RISC other than this article at Register. While India does have large ambitions, executing it is far trickier than most people believe as well as complex and highly capital intensive. The RISC way could be a game-changer provided India moves deftly ahead. FWIW, Debian did a RISC port in 2018. From what I can tell, you can install it on a VM/QEMU and do stuff. And while RISC has its own niches, you never know what happens next.One can speculate a lot and there is certainly a lot of momentum behind RISC. From what little experience I have had, where India has failed time and time again, whether in software or hardware is support. Support is the key, unless that is not fixed, it will remain a dream  On a slightly sad note, Foxconn is withdrawing from the joint venture it had with Vedanta.

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