Search Results: "helmutg"

10 October 2024

Freexian Collaborators: Debian Contributions: Packaging Pydantic v2, Reworking of glib2.0 for cross bootstrap, Python archive rebuilds and more! (by Anupa Ann Joseph)

Debian Contributions: 2024-09 Contributing to Debian is part of Freexian s mission. This article covers the latest achievements of Freexian and their collaborators. All of this is made possible by organizations subscribing to our Long Term Support contracts and consulting services.

Pydantic v2, by Colin Watson Pydantic is a useful library for validating data in Python using type hints: Freexian uses it in a number of projects, including Debusine. Its Debian packaging had been stalled at 1.10.17 in testing for some time, partly due to needing to make sure everything else could cope with the breaking changes introduced in 2.x, but mostly due to needing to sort out packaging of its new Rust dependencies. Several other people (notably Alexandre Detiste, Andreas Tille, Drew Parsons, and Timo R hling) had made some good progress on this, but nobody had quite got it over the line and it seemed a bit stuck. Colin upgraded a few Rust libraries to new upstream versions, packaged rust-jiter, and chased various failures in other packages. This eventually allowed getting current versions of both pydantic-core and pydantic into testing. It should now be much easier for us to stay up to date routinely.

Reworking of glib2.0 for cross bootstrap, by Helmut Grohne Simon McVittie (not affiliated with Freexian) earlier restructured the libglib2.0-dev such that it would absorb more functionality and in particular provide tools for working with .gir files. Those tools practically require being run for their host architecture (practically this means running under qemu-user) which is at odds with the requirements of architecture cross bootstrap. The qemu requirement was expressed in package dependencies and also made people unhappy attempting to use libglib2.0-dev for i386 on amd64 without resorting to qemu. The use of qemu in architecture bootstrap is particularly problematic as it tends to not be ready at the time bootstrapping is needed. As a result, Simon proposed and implemented the introduction of a libgio-2.0-dev package providing a subset of libglib2.0-dev that does not require qemu. Packages should continue to use libglib2.0-dev in their Build-Depends unless involved in architecture bootstrap. Helmut reviewed and tested the implementation and integrated the necessary changes into rebootstrap. He also prepared a patch for libverto to use the new package and proposed adding forward compatibility to glib2.0. Helmut continued working on adding cross-exe-wrapper to architecture-properties and implemented autopkgtests later improved by Simon. The cross-exe-wrapper package now provides a generic mechanism to a program on a different architecture by using qemu when needed only. For instance, a dependency on cross-exe-wrapper:i386 provides a i686-linux-gnu-cross-exe-wrapper program that can be used to wrap an ELF executable for the i386 architecture. When installed on amd64 or i386 it will skip installing or running qemu, but for other architectures qemu will be used automatically. This facility can be used to support cross building with targeted use of qemu in cases where running host code is unavoidable as is the case for GObject introspection. This concludes the joint work with Simon and Niels Thykier on glib2.0 and architecture-properties resolving known architecture bootstrap regressions arising from the glib2.0 refactoring earlier this year.

Analyzing binary package metadata, by Helmut Grohne As Guillem Jover (not affiliated with Freexian) continues to work on adding metadata tracking to dpkg, the question arises how this affects existing packages. The dedup.debian.net infrastructure provides an easy playground to answer such questions, so Helmut gathered file metadata from all binary packages in unstable and performed an explorative analysis. Some results include: Guillem also performed a cursory analysis and reported other problem categories such as mismatching directory permissions for directories installed by multiple packages and thus gained a better understanding of what consistency checks dpkg can enforce.

Python archive rebuilds, by Stefano Rivera Last month Stefano started to write some tooling to do large-scale rebuilds in debusine, starting with finding packages that had already started to fail to build from source (FTBFS) due to the removal of setup.py test. This month, Stefano did some more rebuilds, starting with experimental versions of dh-python. During the Python 3.12 transition, we had added a dependency on python3-setuptools to dh-python, to ease the transition. Python 3.12 removed distutils from the stdlib, but many packages were expecting it to still be available. Setuptools contains a version of distutils, and dh-python was a convenient place to depend on setuptools for most package builds. This dependency was never meant to be permanent. A rebuild without it resulted in mass-filing about 340 bugs (and around 80 more by mistake). A new feature in Python 3.12, was to have unittest s test runner exit with a non-zero return code, if no tests were run. We added this feature, to be able to detect tests that are not being discovered, by mistake. We are ignoring this failure, as we wouldn t want to suddenly cause hundreds of packages to fail to build, if they have no tests. Stefano did a rebuild to see how many packages were affected, and found that around 1000 were. The Debian Python community has not come to a conclusion on how to move forward with this. As soon as Python 3.13 release candidate 2 was available, Stefano did a rebuild of the Python packages in the archive against it. This was a more complex rebuild than the others, as it had to be done in stages. Many packages need other Python packages at build time, typically to run tests. So transitions like this involve some manual bootstrapping, followed by several rounds of builds. Not all packages could be tested, as not all their dependencies support 3.13 yet. The result was around 100 bugs in packages that need work to support Python 3.13. Many other packages will need additional work to properly support Python 3.13, but being able to build (and run tests) is an important first step.

Miscellaneous contributions
  • Carles prepared the update of python-pyaarlo package to a new upstream release.
  • Carles worked on updating python-ring-doorbell to a new upstream release. Unfinished, pending to package a new dependency python3-firebase-messaging RFP #1082958 and its dependency python3-http-ece RFP #1083020.
  • Carles improved po-debconf-manager. Main new feature is that it can open Salsa merge requests. Aiming for a lightning talk in MiniDebConf Toulouse (November) to be functional end to end and get feedback from the wider public for this proof of concept.
  • Carles helped one translator to use po-debconf-manager (added compatibility for bullseye, fixed other issues) and reviewed 17 package templates.
  • Colin upgraded the OpenSSH packaging to 9.9p1.
  • Colin upgraded the various YubiHSM packages to new upstream versions, enabled more tests, fixed yubihsm-shell build failures on some 32-bit architectures, made yubihsm-shell build reproducibly, and fixed yubihsm-connector to apply udev rules to existing devices when the package is installed. As usual, bookworm-backports is up to date with all these changes.
  • Colin fixed quite a bit of fallout from setuptools 72.0.0 removing setup.py test, backported a large upstream patch set to make buildbot work with SQLAlchemy 2.0, and upgraded 25 other Python packages to new upstream versions.
  • Enrico worked with Jakob Haufe to get him up to speed for managing sso.debian.org
  • Rapha l did remove spam entries in the list of teams on tracker.debian.org (see #1080446), and he applied a few external contributions, fixing a rendering issue and replacing the DDPO link with a more useful alternative. He also gave feedback on a couple of merge requests that required more work. As part of the analysis of the underlying problem, he suggested to the ftpmasters (via #1083068) to auto-reject packages having the too-many-contacts lintian error, and he raised the severity of #1076048 to serious to actually have that 4 year old bug fixed.
  • Rapha l uploaded zim and hamster-time-tracker to fix issues with Python 3.12 getting rid of setuptools. He also uploaded a new gnome-shell-extension-hamster to cope with the upcoming transition to GNOME 47.
  • Helmut sent seven patches and sponsored one upload for cross build failures.
  • Helmut uploaded a Nagios/Icinga plugin check-smart-attributes for monitoring the health of physical disks.
  • Helmut collaborated on sbuild reviewing and improving a MR for refactoring the unshare backend.
  • Helmut sent a patch fixing coinstallability of gcc-defaults.
  • Helmut continued to monitor the evolution of the /usr-move. With more and more key packages such as libvirt or fuse3 fixed. We re moving into the boring long-tail of the transition.
  • Helmut proposed updating the meson buildsystem in debhelper to use env2mfile.
  • Helmut continued to update patches maintained in rebootstrap. Due to the work on glib2.0 above, rebootstrap moves a lot further, but still fails for any architecture.
  • Santiago reviewed some Merge Request in Salsa CI, such as: !478, proposed by Otto to extend the information about how to use additional runners in the pipeline and !518, proposed by Ahmed to add support for Ubuntu images, that will help to test how some debian packages, including the complex MariaDB are built on Ubuntu. Santiago also prepared !545, which will make the reprotest job more consistent with the result seen on reproducible-builds.
  • Santiago worked on different tasks related to DebConf 25. Especially he drafted the fundraising brochure (which is almost ready).
  • Thorsten Alteholz uploaded package libcupsfilter to fix the autopkgtest and a dependency problem of this package. After package splix was abandoned by upstream and OpenPrinting.org adopted its maintenance, Thorsten uploaded their first release.
  • Anupa published posts on the Debian Administrators group in LinkedIn and moderated the group, one of the tasks of the Debian Publicity Team.
  • Anupa helped organize DebUtsav 2024. It had over 100 attendees with hand-on sessions on making initial contributions to Linux Kernel, Debian packaging, submitting documentation to Debian wiki and assisting Debian Installations.

10 September 2024

Freexian Collaborators: Debian Contributions: Python 3 patches, OpenSSH GSS-API split, rebootstrap, salsa CI, etc. (by Anupa Ann Joseph)

Debian Contributions: 2024-08 Contributing to Debian is part of Freexian s mission. This article covers the latest achievements of Freexian and their collaborators. All of this is made possible by organizations subscribing to our Long Term Support contracts and consulting services.

Debian Python 3 patch review, by Stefano Rivera Last month, at DebConf, Stefano reviewed the current patch set of Debian s cPython packages with Matthias Klose, the primary maintainer until now. As a result of that review, Stefano re-reviewed the patchset, updating descriptions, etc. A few patches were able to be dropped, and a few others were forwarded upstream. One finds all sorts of skeletons doing reviews like this. One of the patches had been inactive (fortunately, because it was buggy) since the day it was applied, 13 years ago. One is a cleanup that probably only fixes a bug on HPUX, and is a result of copying code from xfree86 into Python 25 years ago. It was fixed in xfree86 a year later. Others support just Debian-specific functionality and probably never seemed worth forwarding. Or good cleanup that only really applies to Debian. A trivial new patch would allow Debian to multiarch co-install Python stable ABI dynamic extensions (like we can with regular dynamic extensions). Performance concerns are stalling it in review, at the moment.

DebConf 24 Organization, by Stefano Rivera Stefano helped organize DebConf 24, which concluded in early August. The event is run by a large entirely volunteer team. The work involved in making this happen is far too varied to describe here. While Freexian provides funding for 20% of collaborator time to spend on Debian-related work, it only covers a small fraction of contributions to time-intensive tasks like this. Since the end of the event, Stefano has been doing some work on the conference finances, and initiated the reimbursement process for travel bursaries.

Archive rebuilds on Debusine, by Stefano Rivera The recent setuptools 73 upload to Debian unstable removed the test subcommand, breaking many packages that were using python3 setup.py test in their Debian packaging. Stefano did a partial archive-rebuild using debusine.debian.net to find the regressions and file bugs. Debusine will be a powerful tool to do QA work like this for Debian in the future, but it doesn t have all the features needed to coordinate rebuild-testing, yet. They are planned to be fleshed out in the next year. In the meantime, Debusine has the building blocks to work through a queue of package building tasks and store the results, it just needs to be driven from outside the system. So, Stefano started working on a set of tools using the Debusine client API to perform archive rebuilds, found and tagged existing bugs, and filed many more.

OpenSSH GSS-API split, by Colin Watson Colin landed the first stage of the planned split of GSS-API authentication and key exchange support in Debian s OpenSSH packaging. In order to allow for smooth upgrades, the second stage will have to wait until after the Debian 13 (trixie) release; but once that s done, as upstream puts it, this substantially reduces the amount of pre-authentication attack surface exposed on your users sshd by default .

OpenSSL vs. cryptography, by Colin Watson Colin facilitated a discussion between Debian s OpenSSL team and the upstream maintainers of Python cryptography about a new incompatibility between Debian s OpenSSL packaging and cryptography s handling of OpenSSL s legacy provider, which was causing a number of build and test failures. While the issue remains open, the Debian OpenSSL maintainers have effectively reverted the change now, so it s no longer a pressing problem.

/usr-move, by Helmut Grohne There are less than 40 source packages left to move files to /usr, so what we re left with is the long tail of the transition. Rather than fix all of them, Helmut started a discussion on removing packages from unstable and filed a first batch. As libvirt is being restructured in experimental, we re handling the fallout in collaboration with its maintainer Andrea Bolognani. Since base-files validates the aliasing symlinks before upgrading, it was discovered that systemd has its own ideas with no solution as of yet. Helmut also proposed that dash checks for ineffective diversions of /bin/sh and that lintian warns about aliased files.

rebootstrap by Helmut Grohne Bootstrapping Debian for a new or existing CPU architecture still is a quite manual process. The rebootstrap project attempts to automate part of the early stage, but it still is very sensitive to changes in unstable. We had a number of fairly intrusive changes this year already. August included a little more fallout from the earlier gcc-for-host work where the C++ include search path would end up being wrong in the generated cross toolchain. A number of packages such as util-linux (twice), libxml2, libcap-ng or systemd had their stage profiles broken. e2fsprogs gained a cycle with libarchive-dev due to having gained support for creating an ext4 filesystem from a tar archive. The restructuring of glib2.0 remains an unsolved problem for now, but libxt and cdebconf should be buildable without glib2.0.

Salsa CI, by Santiago Ruano Rinc n Santiago completed the initial RISC-V support (!523) in the Salsa CI s pipeline. The main work started in July, but it was required to take into account some comments in the review (thanks to Ahmed!) and some final details in [!534]. riscv64 is the most recently supported port in Debian, which will be part of trixie. As its name suggests, the new build-riscv64 job makes it possible to test that a package successfully builds in the riscv64 architecture. The RISC-V runner (salsaci riscv64 runner 01) runs in a couple of machines generously provided by lab.rvperf.org. Debian Developers interested in running this job in their projects should enable the runner (salsaci riscv64 runner 01) in Settings / CI / Runners, and follow the instructions available at https://salsa.debian.org/salsa-ci-team/pipeline/#build-job-on-risc-v. Santiago also took part in discussions about how to optimize the build jobs and reviewed !537 to make the build-source job to only satisfy the Build-Depends and Build-Conflicts fields by Andrea Pappacoda. Thanks a lot to him!

Miscellaneous contributions
  • Stefano submitted patches for BeautifulSoup to support the latest soupsieve and lxml.
  • Stefano uploaded pypy3 7.3.17, upgrading the cPython compatibility from 3.9 to 3.10. Then ran into a GCC-14-related regression, which had to be ignored for now as it s proving hard to fix.
  • Colin released libpipeline 1.5.8 and man-db 2.13.0; the latter included foundations allowing adding an autopkgtest for man-db.
  • Colin upgraded 19 Python packages to new upstream versions (fixing 5 CVEs), fixed several other build failures, fixed a Python 3.12 compatibility issue in zope.security, and made python-nacl build reproducibly.
  • Colin tracked down test failures in python-asyncssh and Ruby resulting from certain odd /etc/hosts configurations.
  • Carles upgraded the packages python-ring-doorbell and simplemonitor to new upstream versions.
  • Carles started discussions and implementation of a tool (still in early days) named po-debconf-manager : a way for translators and reviewers to collaborate using git as a backend instead of mailing list; and submit the translations using salsa MR. More information next month.
  • Carles (dog-fooding po-debconf-manager ) reviewed debconf templates translated by a collaborator.
  • Carles reviewed and submitted the translation of apt .
  • Helmut sent 19 patches for improving cross building.
  • Helmut implemented the cross-exe-wrapper proposed by Simon McVittie for use with glib2.0.
  • Helmut detailed what it takes to make Perl s ExtUtils::PkgConfig suitable for cross building.
  • Helmut made the deletion of the root password work in debvm in all situations and implemented a test case using expect.
  • Anupa attended Debian Publicity team meeting and is moderating and posting on Debian Administrators LinkedIn group.
  • Thorsten uploaded package gutenprint to fix a FTBFS with gcc14 and package ipp-usb to fix a /usr-merge issue.
  • Santiago updated bzip2 to fix a long-standing bug that requested to include a pkg-config file. An important impact of this change is that it makes it possible to use Rust bindings for libbz2 by Sequoia, an implementation of OpenPGP.

13 January 2024

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

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

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

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

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

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

10 December 2023

Freexian Collaborators: Debian Contributions: Python 3.12 preparations, debian-printing, merged-/usr tranisition updates, and more! (by Utkarsh Gupta)

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

Preparing for Python 3.12 by Stefano Rivera Stefano uploaded a few packages in preparation for Python 3.12, including pycxx and cython. Cython has a major new version (Cython 3), adding support for 3.12, but also bringing changes that many packages in Debian aren t ready to build with, yet. Stefano uploaded it to Debian experimental and did an archive rebuild of affected packages, and some analysis of the result. Matthias Klose has since filed bugs for all of these issues.

debian-printing, by Thorsten Alteholz This month Thorsten invested some of the previously obtained money to build his own printlab. At the moment it only consists of a dedicated computer with an USB printer attached. Due to its 64GB RAM and an SSD, building of debian-printing packages is much faster now. Over time other printers will be added and understanding bugs should be a lot easier now. Also Thorsten again adopted two packages, namely mink and ink, and moved them to the debian-printing team.

Merged-/usr transition by Helmut Grohne, et al The dumat analysis tool has been improved in quite some aspects. Beyond fixing false negative diagnostics, it now recognizes protective diversions used for mitigating Multi-Arch: same file loss. It was found that the proposed mitigation for ineffective diversions does not work as expected. Trying to fix it up resulted in more problems, some of which remain unsolved as of this writing. Initial work on moving shared libraries in the essential set has been done. Meanwhile, the wider Debian community worked on fixing all known Multi-Arch: same file loss scenarios. This work is now being driven by Christian Hofstaedler and during the Mini DebConf in Cambridge, Chris Boot, tienne Mollier, Miguel Landaeta, Samuel Henrique, and Utkarsh Gupta sent the other half of the necessary patches.

Miscellaneous contributions
  • Stefano merged patches to support loong64 and hurd-amd64 in re2.
  • For the Cambridge mini-conf, Stefano added a web player to the DebConf video streaming frontend, as the Cambridge miniconf didn t have its own website to host the player.
  • Rapha l helped the upstream developers of hamster-time-tracker to prepare a new upstream release (the first in multiple years) and packaged that new release in Debian unstable.
  • Enrico joined Hemut in brainstorming some /usr-merge solutions.
  • Thorsten took care of RM-bugs to remove no longer needed packages from the Debian archive and closed about 50 of them.
  • Helmut ported the feature of mounting a fuse connection via /dev/fd/N from fuse3 to fuse2.
  • Helmut sent a number of patches simplifying unprivileged use of piuparts.
  • Roberto worked with Helmut to prepare the Shorewall package for the ongoing /usr-move transition.
  • Utkarsh also helped with the ongoing /usr-merge work by preparing patches for gitlab, libnfc, and net-tools.
  • Utkarsh, along with Helmut, brainstormed on fixing #961138, as this affects the whole archive and all the suites and not just R packages. Utkarsh intends to follow up on the bug in December.
  • Santiago organized a MiniDebConf in Uruguay. In total, nine people attended, including most of DDs in the surrounding area. Here s a nicely written blog by Gunnar Wolf.
  • Santiago also worked on some issues on Salsa CI, fixed with some merge requests: #462, #463, and #466.

23 November 2023

Freexian Collaborators: Debian Contributions: Preparing for Python 3.12, /usr-merge updates, invalid PEP-440 versions, and more! (by Utkarsh Gupta)

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

urllib3 s old security patch by Stefano Rivera Stefano ran into a test-suite failure in a new Debian package (python-truststore), caused by Debian s patch to urllib3 from a decade ago, making it enable TLS verification by default (remember those days!). Some analysis confirmed that this patch isn t useful any more, and could be removed. While working on the package, Stefano investigated the scope of the urllib3 2.x transition. It looks ready to start, not many packages are affected.

Preparing for Python 3.12 in dh-python by Stefano Rivera We are preparing to start the Python 3.12 transition in Debian. Two of the upstream changes that are going to cause a lot of packages to break could be worked-around in dh-python, so we did:
  • Distutils is no longer shipped in the Python stdlib. Packages need to Build-Depend on python3-setuptools to get a (compatibility shim) distutils. Until that happens, dh-python will Depend on setuptools.
  • A failure to find any tests to execute will now make the unittest runner exit 5, like pytest does. This was our change, to test-suites that have failed to be automatically discovered. It will cause many packages to fail to build, so until they explicitly skip running test suites, dh-python will ignore these failures.

/usr-merge by Helmut Grohne It has become clear that the planned changes to debhelper and systemd.pc cause more rc-bugs. Helmut researched these systematically and filed another stack of patches. At the time of this writing, the uploads would still cause about 40 rc-bugs. A new opt-in helper dh_movetousr has been developed and added to debhelper in trixie and unstable.

debian-printing, by Thorsten Alteholz This month Thorsten adopted two packages, namely rlpr and lprng, and moved them to the debian-printing team. As part of this Thorsten could close eight bugs in the BTS. Thorsten also uploaded a new upstream version of cups, which also meant that eleven bugs could be closed. As package hannah-foo2zjs still depended on the deprecated policykit-1 package, Thorsten changed the dependency list accordingly and could close one RC bug by the following upload.

Invalid PEP-440 Versions in Python Packages by Stefano Rivera Stefano investigated how many packages in Debian (typically Debian-native packages) recorded versions in their packaging metadata (egg-info directories) that weren t valid PEP-440 Python versions. pip is starting to enforce that all versions on the system are valid.

Miscellaneous contributions
  • distro-info-data updates in Debian, due to the new Ubuntu release, by Stefano.
  • DebConf 23 bookkeeping continues, but is winding down. Stefano still spends a little time on it.
  • Utkarsh continues to monitor and help with reimbursements.
  • Helmut continues to maintain architecture bootstrap and accidentally broke pam briefly
  • Anton uploaded boost1.83 and started to prepare a transition to make boost1.83 as a default boost version.
  • Rejuntada Debian UY 2023, a MiniDebConf that will be held in Montevideo, from 9 to 11 November, mainly organized by Santiago.

20 October 2023

Freexian Collaborators: Debian Contributions: Freexian meetup, debusine updates, lpr/lpd in Debian, and more! (by Utkarsh Gupta, Stefano Rivera)

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

Freexian Meetup, by Stefano Rivera, Utkarsh Gupta, et al. During DebConf, Freexian organized a meetup for its collaborators and those interested in learning more about Freexian and its services. It was well received and many people interested in Freexian showed up. Some developers who were interested in contributing to LTS came to get more details about joining the project. And some prospective customers came to get to know us and ask questions. Sadly, the tragic loss of Abraham shook DebConf, both individually and structurally. The meetup got rescheduled to a small room without video coverage. With that, we still had a wholesome interaction and here s a quick picture from the meetup taken by Utkarsh (which is also why he s missing!).

Debusine, by Rapha l Hertzog, et al. Freexian has been investing into debusine for a while, but development speed is about to increase dramatically thanks to funding from SovereignTechFund.de. Rapha l laid out the 5 milestones of the funding contract, and filed the issues for the first milestone. Together with Enrico and Stefano, they established a workflow for the expanded team. Among the first steps of this milestone, Enrico started to work on a developer-friendly description of debusine that we can use when we reach out to the many Debian contributors that we will have to interact with. And Rapha l started the design work of the autopkgtest and lintian tasks, i.e. what s the interface to schedule such tasks, what behavior and what associated options do we support? At this point you might wonder what debusine is supposed to be let us try to answer this: Debusine manages scheduling and distribution of Debian-related build and QA tasks to a network of worker machines. It also manages the resulting artifacts and provides the results in an easy to consume way. We want to make it easy for Debian contributors to leverage all the great QA tools that Debian provides. We want to build the next generation of Debian s build infrastructure, one that will continue to reliably do what it already does, but that will also enable distribution-wide experiments, custom package repositories and custom workflows with advanced package reviews. If this all sounds interesting to you, don t hesitate to watch the project on salsa.debian.org and to contribute.

lpr/lpd in Debian, by Thorsten Alteholz During Debconf23, Till Kamppeter presented CPDB (Common Print Dialog Backend), a new way to handle print queues. After this talk it was discussed whether the old lpr/lpd based printing system could be abandoned in Debian or whether there is still demand for it. So Thorsten asked on the debian-devel email list whether anybody uses it. Oddly enough, these old packages are still useful:
  • Within a small network it is easier to distribute a printcap file, than to properly configure cups clients.
  • One of the biggest manufacturers of WLAN router and DSL boxes only supports raw queues when attaching an USB printer to their hardware. Admittedly the CPDB still has problems with such raw queues.
  • The Pharos printing system at MIT is still lpd-based.
As a result, the lpr/lpd stuff is not yet ready to be abandoned and Thorsten will adopt the relevant packages (or rather move them under the umbrella of the debian-printing team). Though it is not planned to develop new features, those packages should at least have a maintainer. This month Thorsten adopted rlpr, an utility for lpd printing without using /etc/printcap. The next one he is working on is lprng, a lpr/lpd printer spooling system. If you know of any other package that is also needed and still maintained by the QA team, please tell Thorsten.

/usr-merge, by Helmut Grohne Discussion about lifting the file move moratorium has been initiated with the CTTE and the release team. A formal lift is dependent on updating debootstrap in older suites though. A significant number of packages can automatically move their systemd unit files if dh_installsystemd and systemd.pc change their installation targets. Unfortunately, doing so makes some packages FTBFS and therefore patches have been filed. The analysis tool, dumat, has been enhanced to better understand which upgrade scenarios are considered supported to reduce false positive bug filings and gained a mode for local operation on a .changes file meant for inclusion in salsa-ci. The filing of bugs from dumat is still manual to improve the quality of reports. Since September, the moratorium has been lifted.

Miscellaneous contributions
  • Rapha l updated Django s backport in bullseye-backports to match the latest security release that was published in bookworm. Tracker.debian.org is still using that backport.
  • Helmut Grohne sent 13 patches for cross build failures.
  • Helmut Grohne performed a maintenance upload of debvm enabling its use in autopkgtests.
  • Helmut Grohne wrote an API-compatible reimplementation of autopkgtest-build-qemu. It is powered by mmdebstrap, therefore unprivileged, EFI-only and will soon be included in mmdebstrap.
  • Santiago continued the work regarding how to make it easier to (automatically) test reverse dependencies. An example of the ongoing work was presented during the Salsa CI BoF at DebConf 23.
    In fact, omniorb-dfsg test pipelines as the above were used for the omniorb-dfsg 4.3.0 transition, verifying how the reverse dependencies (tango, pytango and omnievents) were built and how their autopkgtest jobs run with the to-be-uploaded omniorb-dfsg new release.
  • Utkarsh and Stefano attended and helped run DebConf 23. Also continued winding up DebConf 22 accounting.
  • Anton Gladky did some science team uploads to fix RC bugs.

10 September 2023

Freexian Collaborators: Debian Contributions: /usr-merge updates, Salsa CI progress, DebConf23 lead-up, and more! (by Utkarsh Gupta)

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

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

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

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

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

12 July 2023

Freexian Collaborators: Debian Contributions: /usr-merge updates, DebConf Bursary prep, and more! (by Utkarsh Gupta)

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

/usr-merge, by Helmut Grohne, et al The work on /usr-merge continues from May. The lengthy discussion was condensed into a still lengthy rewrite of DEP17 listing all known problems and proposed mitigations. An initial consensus call did not resolve all questions, but we now have rough consensus on finalizing the transition without relying on major changes to dpkg. Other questions still have diverging opinions and some matters such as how to not break backports are still missing satisfying answers.

DebConf Bursary prep, by Utkarsh Gupta DebCamp and DebConf is happening from 03rd September to 17th September in Kochi, India, and the DebConf Bursary team is gearing up for that. After extending the bursary deadline (catering to the requests coming in from various people), we ve finally managed to clock over 260 bursary requests. The team is set up and we re starting to review the applications. The team intends to roll out the result as soon as possible.

debci, by Helmut Grohne As Freexian is working on deploying autopkgtests for the LTS and ELTS services, debci and autopkgtests were improved in Debian to better deal with derivatives (e.g. by better supporting external package signing keyrings). Other aspects that are not deployed on ci.debian.net such as the qemu backend were also improved. We express thanks to the relevant maintainers Antonio Terceiro, Paul Gevers and Simon McVittie for their timely reviews and merges of our changes.

Miscellaneous contributions
  • Following the release of Debian 12, Rapha l Hertzog updated tracker.debian.org to be aware of trixie. He also pushed some fixes to distro-tracker (the software powering tracker.debian.org) and released version 1.2.0 (since the former release was lacking fixes to run on Debian 12 bookworm).
  • Following the release of Debian 12, Helmut Grohne updated crossqa.debian.net systems. He also sent 7 patches for cross build failures and continued adapting rebootstrap to changes in unstable.
  • Santiago Ruano Rinc n started to work on how to improve the robustness of Salsa CI s pipeline for some jobs failing frequently.
  • Thorsten Alteholz did security updates of cpdb-libs in Unstable and Bookworm.
  • Stefano Rivera upgraded pixelfed.debian.social to bookworm.
  • Stefano started an re2 library transition, and started preparation for the next transition.
  • Helmut Grohne updated debvm in unstable releasing changes that accumulated during the freeze.
  • Stefano did some work on the website and infrastructure for DebConf 23.
  • Utkarsh Gupta helped review and fix open redmine bugs and fix them all in unstable.

8 June 2023

Lisandro Dami n Nicanor P rez Meyer: Adventures in Debian's Qt land

Debian (I might as well say "we", this is the beauty of it) is about to release Debian 12 aka Bookworm. Let's take a quick look at what is new in Debian Qt land. Qt 5 Bookworm has Qt 5.15.8, which is nothing but great news. KDE will be switching to Qt 6 sooner than later and Qt 5 has been a fun ride, but Dmitry Shachnev and I needed a break, or at very least not handling two Qt versions. But in the end I need to be fair: you REALLY need to thank Dmitry for Qt 5. He has been the man power behind it in 99.5% of the cases. Qt 6 This will be the first Debian release to have official Qt 6 packages. NOTHING would have happened if it weren't for Patrick "Delta-One" Franz standing up to maintain it. BIG kudos to him! Well, there is a "little lie" in the paragraph above. Thanks to The Qt Company and ICS the current Qt 6 version, 6.4.2, is also available as Bullseye's backports. The Qt Company really also helped us here by providing us almost-to-be-released tarballs of Qt 6.4.2 so we were able to push them to unstable and do a transition in time for freeze, thanks a lot for that! So, what is the Qt 6 state? At the binary side all but OpenGL ES support should be there. Sadly this was discovered too late in the release process and we still might need help maintaining it (read the link to know why!). We are still not building the documentation. Properly building the whole documentation, as with Qt 5, would require all the Qt submodules' source code in one place, which we can't (easily?) do in Debian. So building the doc means hacking the build system and getting semi-linked documentation, much like with Qt 5. Now if you think you have an idea to solve this... we are happy to hear from you! Another great thing to know about Qt 6 is that, thanks to Helmut Grohne, pure Qt 6 applications should be able to cross compile. Applications using multi-arch enabled libraries ought to work too. Even more, many Qt submodules themselves should also cross compile! Not all of them, as we missed some patches in time, but hey, if you need to cross compile Qt, you surely can apply them yourselves! And finally tests, unit tests. In Qt 5 we had some of those, but none yet in Qt 6. This is one of the areas I would love to be able to put time... but time is scarce. The future? In my point of view the Debian 13 "Trixie" development cycle will see Qt 5 diminishing it's usage and Qt 6 becoming the major Qt version used, but from the Qt 4 experience I do not expect Qt 5 being dropped during this release cycle... let's see what the future brings us. Thanks! While I mentioned Dmitry and Patrick many more people helped us reach this place. I personally want to thank the people behind the KDE software, both upstream and, of course, the Debian maintainers. You should be thankful with them too, many hours of effort go into this. And thanks to you our dear users. We are normally overflowed with what we have in our hands and might not be up to the task sometimes, but hey, you are part of the reason we are doing this!

27 September 2017

Enrico Zini: Qt cross-architecture development in Debian

Use case: use Debian Stable as an environment to run amd64 development machines to develop Qt applications for Raspberry Pi or other smallish armhf devices. Qt Creator is used as Integrated Development Environment, and it supports cross-compiling, running the built source on the target system, and remote debugging. Debian Stable (vanilla or Raspbian) runs on both the host and the target systems, so libraries can be kept in sync, and both systems have access to a vast amount of libraries, with security support. On top of that, armhf libraries can be installed with multiarch also in the host machine, so cross-builders have access to the exact same libraries as the target system. This sounds like a dream system. But. We're not quite there yet. cross-compile attempts I tried cross compiling a few packages:
$ sudo debootstrap stretch cross
$ echo "strech_cross"   sudo tee cross/etc/debian_chroot
$ sudo systemd-nspawn -D cross
# dpkg --add-architecture armhf
# echo "deb-src http://deb.debian.org/debian stretch main" >> /etc/apt/sources.list
# apt update
# apt install --no-install-recommends build-essential crossbuild-essential-armhf
Some packages work:
# apt source bc
# cd bc-1.06.95/
# apt-get build-dep -a armhf .
# dpkg-buildpackage -aarmhf -j2 -b
 
dh_auto_configure -- --prefix=/usr --with-readline
        ./configure --build=x86_64-linux-gnu --prefix=/usr --includedir=\$ prefix /include --mandir=\$ prefix /share/man --infodir=\$ prefix /share/info --sysconfdir=/etc --localstatedir=/var --disable-silent-rules --libdir=\$ prefix /lib/arm-linux-gnueabihf --libexecdir=\$ prefix /lib/arm-linux-gnueabihf --disable-maintainer-mode --disable-dependency-tracking --host=arm-linux-gnueabihf --prefix=/usr --with-readline
 
dpkg-deb: building package 'dc-dbgsym' in '../dc-dbgsym_1.06.95-9_armhf.deb'.
dpkg-deb: building package 'bc-dbgsym' in '../bc-dbgsym_1.06.95-9_armhf.deb'.
dpkg-deb: building package 'dc' in '../dc_1.06.95-9_armhf.deb'.
dpkg-deb: building package 'bc' in '../bc_1.06.95-9_armhf.deb'.
 dpkg-genbuildinfo --build=binary
 dpkg-genchanges --build=binary >../bc_1.06.95-9_armhf.changes
dpkg-genchanges: info: binary-only upload (no source code included)
 dpkg-source --after-build bc-1.06.95
dpkg-buildpackage: info: binary-only upload (no source included)
With qmake based Qt packages, qmake is not configured for cross-building, probably because it is not currently supported:
# apt source pumpa
# cd pumpa-0.9.3/
# apt-get build-dep -a armhf .
# dpkg-buildpackage -aarmhf -j2 -b
 
        qmake -makefile -nocache "QMAKE_CFLAGS_RELEASE=-g -O2 -fdebug-prefix-map=/root/pumpa-0.9.3=.
          -fstack-protector-strong -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2"
          "QMAKE_CFLAGS_DEBUG=-g -O2 -fdebug-prefix-map=/root/pumpa-0.9.3=. -fstack-protector-strong
          -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2"
          "QMAKE_CXXFLAGS_RELEASE=-g -O2 -fdebug-prefix-map=/root/pumpa-0.9.3=. -fstack-protector-strong
          -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2"
          "QMAKE_CXXFLAGS_DEBUG=-g -O2 -fdebug-prefix-map=/root/pumpa-0.9.3=. -fstack-protector-strong
          -Wformat -Werror=format-security -Wdate-time -D_FORTIFY_SOURCE=2"
          "QMAKE_LFLAGS_RELEASE=-Wl,-z,relro -Wl,-z,now"
          "QMAKE_LFLAGS_DEBUG=-Wl,-z,relro -Wl,-z,now" QMAKE_STRIP=: PREFIX=/usr
qmake: could not exec '/usr/lib/x86_64-linux-gnu/qt5/bin/qmake': No such file or directory
 
debian/rules:19: recipe for target 'build' failed
make: *** [build] Error 2
dpkg-buildpackage: error: debian/rules build gave error exit status 2
With cmake based Qt packages it goes a little better in that it finds the cross compiler, pkg-config and some multiarch paths, but then it tries to run armhf moc, which fails:
# apt source caneda
# cd caneda-0.3.0/
# apt-get build-dep -a armhf .
# dpkg-buildpackage -aarmhf -j2 -b
 
        cmake .. -DCMAKE_INSTALL_PREFIX=/usr -DCMAKE_VERBOSE_MAKEFILE=ON -DCMAKE_BUILD_TYPE=None
          -DCMAKE_INSTALL_SYSCONFDIR=/etc -DCMAKE_INSTALL_LOCALSTATEDIR=/var -DCMAKE_SYSTEM_NAME=Linux
          -DCMAKE_SYSTEM_PROCESSOR=arm -DCMAKE_C_COMPILER=arm-linux-gnueabihf-gcc
          -DCMAKE_CXX_COMPILER=arm-linux-gnueabihf-g\+\+
          -DPKG_CONFIG_EXECUTABLE=/usr/bin/arm-linux-gnueabihf-pkg-config
          -DCMAKE_INSTALL_LIBDIR=lib/arm-linux-gnueabihf
 
CMake Error at /usr/lib/arm-linux-gnueabihf/cmake/Qt5Core/Qt5CoreConfig.cmake:27 (message):
  The imported target "Qt5::Core" references the file
     "/usr/lib/arm-linux-gnueabihf/qt5/bin/moc"
  but this file does not exist.  Possible reasons include:
  * The file was deleted, renamed, or moved to another location.
  * An install or uninstall procedure did not complete successfully.
  * The installation package was faulty and contained
     "/usr/lib/arm-linux-gnueabihf/cmake/Qt5Core/Qt5CoreConfigExtras.cmake"
  but not all the files it references.
Note: Although I improvised a chroot to be able to fool around with it, I would use pbuilder or sbuild to do the actual builds. Helmut suggests pbuilder --host-arch or sbuild --host. Doing it the non-Debian way This guide in the meantime explains how to set up a cross-compiling Qt toolchain in a rather dirty way, by recompiling Qt pointing it at pieces of the Qt deployed on the Raspberry Pi. Following that guide, replacing the CROSS_COMPILE value with /usr/bin/arm-linux-gnueabihf- gave me a working qtbase, for which it is easy to create a Kit for Qt Creator that works, and supports linking applications with Debian development packages that do not use Qt. However, at that point I need to recompile all dependencies that use Qt myself, and I quickly got stuck at that monster of QtWebEngine, whose sources embed the whole of Chromium. Having a Qt based development environment in which I need to become the maintainer for the whole Qt toolchain is not a product I can offer to a customer. Cross compiling qmake based packages on stretch is not currently supported, so at the moment I had to suggest to postpone all plans for total world domination for at least two years. Cross-building Debian In the meantime, Helmut Grohne has been putting a lot of effort into making Debian packages cross-buildable:
helmut> enrico: yes, cross building is painful. we have ~26000 source packages. of those, ~13000 build arch-dep packages. of those, ~6000 have cross-satisfiable build-depends. of those, I tried cross building ~2300. of those 1300 cross built. so we are at about 10% working. helmut> enrico: plus there are some 607 source packages affected by some 326 bugs with patches. helmut> enrico: gogo nmu them helmut> enrico: I've filed some 1000 bugs (most of them with patches) now. around 600 are fixed :)
He is doing it mostly alone, and I would like people not to be alone when they do a lot of work in Debian, so Join Helmut in the effort of making Debian cross-buildable! Build any Debian package for any device right from the comfort of your own work computer! Have a single development environment seamlessly spanning architecture boundaries, with the power of all that there is in Debian! Join Helmut in the effort of making Debian cross-buildable! Apply here, or join #debian-bootstrap on OFTC! Cross-building Qt in Debian mitya57 summarised the situation on the KDE team side:
mitya57> we have cross-building stuff on our TODO list, but it will likely require a lot of time and neither Lisandro nor I have it currently. mitya57> see https://gobby.debian.org/export/Teams/KDE/qt-cross for a summary of what needs to be done. mitya57> Any help or patches are always welcome :))
qemu-user-static Helmut also suggested to use qemu-user-static to make the host system able to run binaries compiled for the target system, so that even if a non-cross-compiling Qt build tries to run moc and friends in their target architecture version, they would transparently succeed. At that point, it would just be a matter of replacing compiler paths to point to the native cross-compiling gcc, and the build would not be slowed down by much. Fixing bug #781226 would help in making it possible to configure a multiarch version of qmake as the qmake used for cross compiling. I have not had a chance of trying to cross-build in this way yet. In the meantime... Having qtcreator able to work on an amd64 devel machine and deploy/test/debug remotely on an arm target machine, where both machine run debian stable and have libraries in sync, would be a great thing to have even though packages do not cross-build yet. Helmut summarised the situation on IRC:
svuorela and others repeat that Qt upstream is not compatible with Debian's multiarch thinking, in that Qt upstream insists on having one toolchain for each pair of architectures, whereas the Debian way tends to be to make packages generic and split stuff such that it can be mixed and matched. An example being that you need to run qmake (thus you need qmake for the build architecture), but qmake also embeds the relevant paths and you need to query it for them (so you need qmake for the host architecture) Either you run it through qemu, or you have a particular cross qmake for your build/host pair, or you fix qt upstream to stop this madness
Building qmake in Debian for each host-target pair, even just limited to released architectures, would mean building Qt 100 times, and that's not going to scale. I wonder:

22 April 2017

Manuel A. Fernandez Montecelo: Debian GNU/Linux port for RISC-V 64-bit (riscv64)

This is a post describing my involvement with the Debian GNU/Linux port for RISC-V (unofficial and not endorsed by Debian at the moment) and announcing the availability of the repository (still very much WIP) with packages built for this architecture. If not interested in the story but you want to check the repository, just jump to the bottom. Roots A while ago, mostly during 2014, I was involved in the Debian port for OpenRISC (or1k) about which I posted (by coincidence) exactly 2 years ago. The two of us working on the port stopped in August or September of that year, after knowing that the copyright of the code to add support for this architecture in GCC would not be assigned to the FSF, so it would never be added to GCC upstream unless the original authors changed their mind (which they didn't) or there was a clean-room reimplementation (which didn't happen so far). But a few other key things contributed to the decision to stop working on that port, which bear direct relationship to this story. One thing that particularly influenced me to stop working on it was a sense of lack of purpose, all things considered, for the OpenRISC port that we were working on. For example, these chips are sometimes used as part of bigger devices by Samsung to control or wake up other chips; but it was not clear whether there would ever be devices with OpenRISC as the main chip, specially in devices powerful enough to run Linux or similar kernels, and Debian on top. One can use FPGAs to synthesise OpenRISC or1k, but these are slow, and expensive when using lots of memory. Without prospects of having hardware easily available to users, there's not much point in having a whole Debian port ready to run on hardware that never comes to be. Yeah, sure, it's fun to create such a port, but it's tons of work to maintain and keep it up to-date forever, and with close to zero users it's very unrewarding. Another thing that contributed to decide to stop is that, at least in my opinion, 32-bit was not future-proof enough for general purpose computing, specially for new devices and ports starting to take off on that time and age. There was some incipient work to create another OpenRISC design for 64-bits, but it was still in an early phase. My secret hope and ultimate goal was to be able to run as much a free-ish computer as possible as my main system. Still today many people are buying and using 32-bit devices, like small boards; but very few use it as their main computer or servers for demanding workloads or complex services. So for me, even if feasible if one is very austere and dedicated, OpenRISC or1k failed that test. And lastly, another thing happened at the time... Enter RISC-V In August 2014, at the point when we were fully acknowledging the problem of upstreaming (or rather, lack thereof) the support for OpenRISC in GCC, RISC-V was announced to the world, bringing along papers with suggestive titles such as Instruction Sets Should Be Free: The Case For RISC-V (pdf) and articles like RISC-V: An Open Standard for SoCs - The case for an open ISA in EE Times. RISC-V (as the previous RISC-n marks) had been designed (or rather, was being designed, because it was and is an as yet unfinished standard) by people from UC Berkeley, including David Patterson, the pioneer of RISC computer designs and co-author of the seminal book Computer Architecture: A Quantitative Approach . Other very capable people are also also leading the project, doing the design and legwork to make it happen see the list of contributors. But, apart from throwing names, the project has many other merits. Similarly to OpenRISC, RISC-V is an open instruction set architecture (ISA), but with the advantage of being designed in more recent times (thus avoiding some mistakes and optimising for problems discovered more recently, as technology evolves); with more resources; with support for instruction widths of 32, 64 and even 128 bits; with a clean set of standard but optional extensions (atomics, float, double, quad, vector, ...); and with reserved space to add new extensions in ordered and compatible ways. In the view of some people in the OpenRISC community, this unexpected development in a way made irrelevant the ongoing update of OpenRISC for 64-bits, and from what I know and for better or worse, all efforts on that front stopped. Also interestingly (if nothing else, for my purposes of running as much a free system as possible), was that the people behind RISC-V had strong intentions to make it useful to create modern hardware, and were pushing heavily towards it from the beginning. And together with this announcement or soonly after, it came the promise of free-ish hardware in the form of the lowRISC project. Although still today it seems to be a long way from actually shipping hardware, at least there was some prospect of getting it some day. On top of all that, about the freedom aspect, both the Berkeley and lowRISC teams engaged since very early on with the free hardware community, including attending and presenting at OpenRISC events; and lowRISC intended to have as much free hardware as possible in their planned SoC. Starting to work on the Debian port, this time for RISC-V So in late 2014 I slowly started to prepare the Debian port, switching on and off. The Userland spec was frozen in 2014 just before the announcement, the Privilege one is still not frozen today, so there was no need to rush. There were plans to upstream the support in the toolchain for RISC-V (GNU binutils, glibc and GCC; Linux and other useful software like Qemu) in 2015, but sadly these did not materialise until late 2016 and 2017. One of the main reasons for the delay was due to the slowness to sort out the copyright assignment of the code to the FSF (again). Still today, only binutils and GCC are upstreamed, and Linux and glibc depend on the Privilege spec being finished, so it will take a while. After the experience with OpenRISC and the support in GCC, I didn't want to invest too much time, lest it all became another dead-end due to lack of upstreaming so I was just cross-compiling here and there, testing Qemu (which still today is very limited for this architecture, e.g. no network support and very limited character and block devices) and trying to find and report bugs in the implementations, and send patches (although I did not contribute much in the end). Incompatible changes in the toolchain In terms of compiling packages and building-up a repository, things were complicate, and less mature and stable than the OpenRISC ones were even back in 2014. In theory, with the Userland spec being frozen, regular programs (below the Operating System level) compiled at any time could have run today; but in practice what happened is that there were several rounds of profound or, at least, disrupting changes in the toolchain before and while being upstreamed, which made the binary packages that I had built to not work at all (changes in dynamic loader, registers where arguments are stored when jumping functions, etc.). These major breakages happened several times already, and kind of unexpectedly at least for the people not heavily involved in the implementation. When the different pieces are upstreamed it is expected that these breakages won't happen; but still there's at least the fundamental bit of glibc, which will probably change things once again in incompatible ways before or while being upstreamed. Outside Debian but within the FOSS / Linux world, the main project that I know of is that some people from Fedora also started a port in mid 2016 and did great advances, but from what I know they put the project in the freezer in late 2016 until all such problems are resolved they don't want to spend time rebootstrapping again and again. What happened recently on the Debian front In early 2016 I created the page for RISC-V in the Debian wiki, expecting that things were at last fully stable and the important bits of the toolchain upstreamed during that year I was too optimistic. Some other people (including Debian folks) have been contributing for a while, in the wiki, mailing lists and IRC channels, and in the RISC-V project mailing lists you will see their names everywhere. However, due to the combination of lack of hardware, software not upstreamed and shortcomings of emulators (chiefly Qemu) make contributions hard and very tedious, nothing much happened recently visible to the outside world in terms of software. The private repository-in-the-making In late 2015 and beginning of 2016, having some free time in my hands and expecting that all things would coalesce quickly, I started to build a repository of binary packages in a more systematic way, with most of the basic software that one can expect in a basic Debian system (including things common to all Linux systems, and also specific Debian software like dpkg or apt, and even aptitude!). After that I also built many others outside the basic system (more than 1000 source packages and 2000 or 3000 arch-dependent binary packages in total), specially popular libraries (e.g. boost, gtk+ version 2 and 3), interpreters (several versions of lua, perl and python, also version 2 and 3) and in general packages that are needed to build many other packages (like doxygen). Unfortunately, some of these most interesting packages do not compile cleanly (more because of obscure or silly errors than proper porting), so they are not included at the moment. I intentionally avoided trying to compile thousands of packages in the archive which would be of nobody's use at this point; but many more could be compiled without much effort. About the how, initially I started cross-compiling and using rebootstrap, which was of great help in the beginning. Some of the packages that I cross-compiled had bugs that I did not know how to debug without a live and native (within emulators) system, so I tried to switch to natively built packages very early on. For that I needed many packages built natively (like doxygen or cmake) which would be unnecessary if I remained cross-compiling the host tools would be used in that case. But this also forced me to eat my own dog food, which even if much slower and tedious, it was on the whole a more instructive experience; and above all, it helped to test and make sure that the the tools and the whole stack was working well enough to build hundreds of packages. Why the repository-in-the-making was private Until now I did not attempt to make the repository available on-line, for several reasons. First because it would be kind of useless to publish files that were not working or would soon not work, due to the incompatible changes in the toolchain, rendering many or most of the packages built useless. And because, for many months now, I expected that things would stabilise and to have something stable really soon now but this didn't happen yet. Second because of lack of resources and time since mid 2016, and because I got some packages only compiled thanks to (mostly small and unimportant, but undocumented and unsaved) hacks, often working around temporary bugs and thus not worth sending upstream; but I couldn't share the binaries without sharing the full source and fulfill licenses like the GNU GPL. I did a new round of clean rebuilds in the last few weeks, just finished, the result is close to 1000 arch-dependent packages. And third, because of lack of demand. This changed in the last few weeks, when other people started to ask me to share the results even if incomplete or not working properly (I had one request in the past, but couldn't oblige in time at the time). Finally, the work so far: repository now on-line So finally, with the great help from Kurt Keville from MIT, and Bytemark sponsoring a machine where most of the packages were built, here we have the repository: The lines for /etc/apt/sources.list are:
 deb [ arch=riscv64 signed-by=/usr/share/keyrings/debian-keyring.gpg ] http://riscv.mit.edu/debian unstable main
 deb-src [ signed-by=/usr/share/keyrings/debian-keyring.gpg ] http://riscv.mit.edu/debian unstable main
The repository is signed with my key as Debian Developer, contained in the file /usr/share/keyrings/debian-keyring.gpg, which is part of the package debian-keyring (available from Debian and derivatives). WARNING!! This repository, though, is very much WIP, incomplete (some package dependencies cannot be fulfilled, and it's only a small percentage of the Debian archive, not trying to be comprehensive at the moment) and probably does not work at all in your system at this point, for the following reasons: The combination of all these shortcomings is specially unfortunate, because without glibc provided it will be difficult that you can get the binaries to run at all; but there are some packages that are arch-dependent but not too tied to libc or the dynamic loader will not be affected. At least you can try one the few static packages present in Debian, like the one in the package bash-static. When one removes moving parts like the dynamic loader and libc, since the basic machine instructions are stable for several years now, it should work, but I wouldn't discard some dark magic that prevents even static binaries from working. Still, I hope that the respository in its current state is useful to some people, at least for those who requested it. If one has the environment set-up, it's easy to unpack the contents of the .deb files and try out the software (which often is not trivial or very slow to compile, or needs lots of dependencies to be built first first). ... and finally, even if not useful at all for most people at the moment, by doing this I also hope that efforts like this spark your interest to contribute to free software, free hardware, or both! :-)

15 June 2016

Reproducible builds folks: Reproducible builds: week 59 in Stretch cycle

What happened in the Reproducible Builds effort between June 5th and June 11th 2016: Media coverage Ed Maste gave a talk at BSDCan 2016 on reproducible builds (slides, video). GSoC and Outreachy updates Weekly reports by our participants: Documentation update - Ximin Luo proposed a modification to our SOURCE_DATE_EPOCH spec explaining FORCE_SOURCE_DATE. Some upstream build tools (e.g. TeX, see below) have expressed a desire to control which cases of embedded timestamps should obey SOURCE_DATE_EPOCH. They were not convinced by our arguments on why this is a bad idea, so we agreed on an environment variable FORCE_SOURCE_DATE for them to implement their desired behaviour - named generically, so that at least we can set it centrally. For more details, see the text just linked. However, we strongly urge most build tools not to use this, and instead obey SOURCE_DATE_EPOCH unconditionally in all cases. Toolchain fixes Packages fixed The following 16 packages have become reproducible due to changes in their build-dependencies: apertium-dan-nor apertium-swe-nor asterisk-prompt-fr-armelle blktrace canl-c code-saturne coinor-symphony dsc-statistics frobby libphp-jpgraph paje.app proxycheck pybit spip tircd xbs The following 5 packages are new in Debian and appear to be reproducible so far: golang-github-bowery-prompt golang-github-pkg-errors golang-gopkg-dancannon-gorethink.v2 libtask-kensho-perl sspace The following packages had older versions which were reproducible, and their latest versions are now reproducible again after being fixed: The following packages have become reproducible after being fixed: Some uploads have fixed some reproducibility issues, but not all of them: Patches submitted that have not made their way to the archive yet: Package reviews 68 reviews have been added, 19 have been updated and 28 have been removed in this week. New and updated issues: 26 FTBFS bugs have been reported by Chris Lamb, 1 by Santiago Vila and 1 by Sascha Steinbiss. diffoscope development strip-nondeterminism development disorderfs development tests.reproducible-builds.org Misc. Steven Chamberlain submitted a patch to FreeBSD's makefs to allow reproducible builds of the kfreebsd installer. Ed Maste committed a patch to FreeBSD's binutils to enable determinstic archives by default in GNU ar. Helmut Grohne experimented with cross+native reproductions of dash with some success, using rebootstrap. This week's edition was written by Ximin Luo, Chris Lamb, Holger Levsen, Mattia Rizzolo and reviewed by a bunch of Reproducible builds folks on IRC.

5 June 2014

Johannes Schauer: botch updates

My last update about ongoing development of botch, the bootstrap/build ordering tool chain, was four months ago and about several incremental updates. This post will be of similar nature. The most interesting news is probably the additional data that bootstrap.debian.net now provides. This is listed in the next section. All subsequent sections then list the changes under the hood that made the additions to bootstrap.debian.net possible.

bootstrap.debian.net The bootstrap.debian.net service used to have botch as a git submodule but now runs botch from its Debian package. This at least proves that the botch Debian package is mature enough to do useful stuff with it. In addition to the bootstrapping results by architecture, bootstrap.debian.net now also hosts the following additional services: Further improvements concern how dependency cycles are now presented in the html overviews. While before, vertices in a cycle where separated by commas as if they were simple package lists, vertices are now connected by unicode arrows. Dashed arrows indicate build dependencies while solid arrows indicate builds-from relationships. For what it's worth, installation set vertices now contain their installation set in their title attribute.

Debian package Botch has long depended on features of an unreleased version of dose3 which in turn depended on an unrelease version of libcudf. Both projects have recently made new releases so that I was now able to drop the dose3 git submodule and rely on the host system's dose3 version instead. This also made it possible to create a Debian package of botch which currently sits at Debian mentors. Writing the package also finally made me create a usable install target in the Makefile as well as adding stubs for the manpages of the 44 applications that botch currently ships. The actual content of these manpages still has to be written. The only documentation botch currently ships in the botch-doc package is an offline version of the wiki on gitorious. The new page ExamplesGraphs even includes pictures.

Cross By default, botch analyzes the native bootstrapping phase. That is, assume that the initial set of Essential:yes and build-essential packages magically exists and find out how to bootstrap the rest from there through native compilation. But part of the bootstrapping problem is also to create the set of Essential:yes and build-essential packages from nothing via cross compilation. Botch is unable to analyze the cross phase because too many packages cannot satisfy their crossbuild dependencies due to multiarch conflicts. This problem is only about the dependency metadata and not about whether a given source package actually crosscompiles fine in practice. Helmut Grohne has done great work with rebootstrap which is regularly run by jenkins.debian.net. He convinced me that we need an overview of what packages are blocking the analysis of the cross case and that it was useful to have a crossbuild order even if that was a fake order just to have a rough overview of the current situation in Debian Sid. I wrote a couple of scripts which would run dose-builddebcheck on a repository, analyze which packages fail to satisfy their crossbuild dependencies and why, fix those cases by adjusting package metadata accordingly and repeat until all relevant source packages satisfy their crossbuild dependencies. The result of this can then be used to identify the packages that need to be modified as well as to generate a crossbuild order. The fixes to the metadata are done in an automatic fashion and do not necessarily reflect the real fix that would solve the problem. Nevertheless, I ended up agreeing that it is better to have a slightly wrong overview than no overview at all.

Minimizing the dependency graph size Installation sets in the dependency graph are calculated independent from each other. If two binary packages provide A, then dependencies on A in different installation sets might choose different binary packages as providers of A. The same holds for disjunctive dependencies. If a package depends on A C and another package depends on C A then there is no coordination to choose C so to minimize the overall amount of vertices in the graph. I implemented two methods to minimize the impact of cases where the dependency solver has multiple options to satisfy a dependency through Provides and dependency disjunctions. The first method is inspired by Helmut Grohne. An algorithm goes through all disjunctive binary dependencies and removes all virtual packages, leaving only real packages. Of the remaining real packages, the first one is selected. For build dependencies, the algorithm drops all but the first package in every disjunction. This is also what sbuild does. Unfortunately this solution produces an unsatisfiable dependency situation in most cases. This is because oftentimes it is necessary to select the virtual disjunctive dependency because of a conflict relationship introduced by another package. The second method involves aspcud, a cudf solver which can optimize a solution by a criteria. This solution is based on an idea by Pietro Abate who implemented the basis for this idea back in 2012. In contrast to a usual cudf problem, binary packages now also depend on the source packages they build from. If we now ask aspcud to find an installation set for one of the base source packages (I chose src:build-essential) then it will return an installation set that includes source packages. As an optimization criteria the number of source packages in the installation set is minimized. This solution would be flawless if there were no conflicts between binary packages. Due to conflicts not all binary packages that must be coinstallable for this strategy to work can be coinstalled. The quick and dirty solution is to remove all conflicts before passing the cudf universe to aspcud. But this also means that the solution does sometimes not work in practice.

Test cases Botch now finally has a test target in its Makefile. The test target tests two code paths of the native.sh script and the cross.sh script. Running these two scripts covers testing most parts of botch. Given that I did lots of refactoring in the past weeks, the test cases greatly helped to assure that I didnt break anything in the process. I also added autopkgtests to the Debian packaging which test the same things as the test target but naturally run the installed version of botch instead. The autopkgtests were a great help in weeding out some lasts bugs which made botch depend on being executed from its source directory.

Python 3 Reading the suggestions in the Debian python policy I evaluated the possibility to use Python 3 for the Python scripts in botch. While I was at it I added transparent decompression for gzip, bz2 and xz based on the file magic, replaced python-apt with python-debian because of bug#748922 and added argparse argument parsing to all scripts. Unfortunately I had to find out that Python 3 support does not yet seem to be possible for botch for the following reasons:
  • no soap module for Python 3 in Debian (needed for bts access)
  • hash randomization is turned on by default in Python 3 and therefore the graph output of networkx is not deterministic anymore (bug#749710)
Thus I settled for changing the code such that it would be compatible with Python 2 as well as with Python 3. Because of the changed string handling and sys.stdout properties in Python 3 this proved to be tricky. On the other hand this showed me bugs in my code where I was wrongly relying on deterministic dictionary key traversal.