Linux Weekly News

Alan Jowett returned for a second remote presentation at the 2024 Linux Storage, Filesystem, Memory Management, and BPF Summit to compare the performance of different BPF runtimes. He showed the results of the MIT-licensed BPF microbenchmark suite he has been working on. The benchmark suite does not yet provide a good direct comparison between all platforms, so the results should be taken with a grain of salt. They do seem to indicate that there is some significant variation between implementations, especially for different types of BPF maps.

Security updates have been issued by Fedora (deepin-qt5integration, deepin-qt5platform-plugins, dotnet8.0, dwayland, fcitx-qt5, fcitx5-qt, gammaray, kddockwidgets, keepassxc, kf5-akonadi-server, kf5-frameworkintegration, kf5-kwayland, plasma-integration, python-qt5, qadwaitadecorations, qgnomeplatform, qt5, qt5-qt3d, qt5-qtbase, qt5-qtcharts, qt5-qtconnectivity, qt5-qtdatavis3d, qt5-qtdeclarative, qt5-qtdoc, qt5-qtgamepad, qt5-qtgraphicaleffects, qt5-qtimageformats, qt5-qtlocation, qt5-qtmultimedia, qt5-qtnetworkauth, qt5-qtquickcontrols, qt5-qtquickcontrols2, qt5-qtremoteobjects, qt5-qtscript, qt5-qtscxml, qt5-qtsensors, qt5-qtserialbus, qt5-qtserialport, and qt5-qtspeech), Oracle (389-ds-base and ruby:3.1), Red Hat (389-ds-base, glibc, and kernel), SUSE (python-PyMySQL), and Ubuntu (libarchive).

We have just received the sad news that longtime core BSD developer Mike Karels has died; he will certainly be missed.

Version 6.2 of the Incus container-management system is out. "This release contains the second wave of changes contributed by students of the University of Texas at Austin and a few other features and improvements." The features include a new incus top command, a new API for system load information, and more.

In the recent discussion on commenting at LWN, several readers asked for the ability to hide subthreads of a long comment stream. That feature has just been added; it is also integrated with the three comment-display modes and with comment filtering, removing the need for JavaScript for filtering. Hiding is not persistent; no extra data is stored at either end.

Give it a try; if you have comments on the new mechanism, this is the place to put them.

The saga of the i_version field for inodes, which tracks the occurrence of changes to the data or metadata of a file, continued in a discussion at the 2024 Linux Storage, Filesystem, Memory Management, and BPF Summit. In a session led by Jeff Layton, who has been doing a lot the work on changing the semantics and functioning of i_version over the years, he updated attendees on the status of the effort since a session at last year's summit. His summary was that things are "pretty much where we started last year", but the discussion this time pointed to some possible ways forward.

There are few topics as arcane as memory models, so it was a pleasant surprise when the double-length session on the BPF memory model at the Linux Storage, Filesystem, Memory Management, and BPF Summit turned out to be understandable. Paul McKenney led the session, although he was clear that the work he was presenting was also due to Puranjay Mohan, who unfortunately could not attend the summit. BPF does not actually have a formalized memory model yet; instead it has relied on a history of talks like this one and a general informal understanding. Unfortunately, ignoring memory models does not make them go away, and this has already caused at least one BPF-related bug on weakly-ordered architectures. Figuring out what a formal memory model for BPF should define was the focus of McKenney's talk.

Security updates have been issued by Mageia (chromium-browser-stable, git, libreoffice, microcode, python-requests, webkit2, and wireshark), Oracle (container-tools:ol8, glibc, go-toolset:ol8, idm:DL1 and idm:client, less, python39:3.9 and python39-devel:3.9, ruby:3.0, and virt:ol and virt-devel:rhel), Red Hat (nodejs, nodejs:18, python-idna, and ruby:3.1), and SUSE (389-ds, ffmpeg, ffmpeg-4, gnutls, gstreamer-plugins-base, libhtp, mariadb104, poppler, python-python-jose, squid, and unbound).

Version 2.4.0 of the LyX document processor has been released. LyX is a "What You See Is What You Mean" (WYSIWYM) application that offers GUI editing of LaTeX documents with import and export to PDF, HTML, OpenDocument, Word, and other formats. LyX 2.4.0 is the first major release in six years, and brings support for EPUB, DocBook 5, improved table styles, and now uses Unicode (utf8) as its default encoding. See the full list of new features on the LyX wiki, and release notes for information on known issues and caveats for those upgrading from earlier versions of LyX.

Debian had a major discussion about mounting /tmp as a RAM-based tmpfs in 2012 but inertia won out in the end. Debian systems have continued to store temporary files on disk by default. Until now. A mere 12 years later, the project will be switching to a RAM-based /tmp in the Debian 13 ("Trixie") release. Additionally, starting with Trixie, the default will be to periodically clean up temporary files automatically in /tmp and /var/tmp. Naturally, it involved a lengthy discussion first.

Security updates have been issued by AlmaLinux (python39:3.9 and python39-devel:3.9 and ruby:3.0), Debian (chromium, gst-plugins-base1.0, and kernel), Fedora (chromium, glances, glycin-loaders, gnome-tour, helix, helvum, kitty, libarchive, libipuz, librsvg2, loupe, maturin, ntpd-rs, plasma-workspace, and a huge list of Rust-based packages due to a "mini-mass-rebuild" that updated the toolchain to Rust 1.78 and picked up fixes for various pieces), Mageia (gifsicle, netatalk, openssl, python-jinja2, and unbound), Red Hat (kernel and kernel-rt), SUSE (bind, glibc, gstreamer-plugins-base, squid, and tiff), and Ubuntu (glibc).

The second 6.10 kernel prepatch is out for testing. "Nothing feels particularly odd, but rc2 is usually fairly small and people are only starting to find regressions. So please go test some more."

The Fedora Project has announced the results of the Fedora Linux 40 election cycle. Four seats were open on the Fedora Engineering Steering Committee (FESCo), and the winners are Stephen Gallagher, Neal Gompa, Michel Lind, and Fabio Valentini. The Fedora Council had two seats open, and the winners are Aleksandra Fedorova and Adam Samalik. One seat was open on the Fedora Mindshare Committee, and the winner is Sumantro Mukherjee. Four seats were open for the first election to select members of the EPEL Steering Committee, which went to Troy Dawson, Kevin Fenzi, Carl George, and Jonathan Wright.

KDE Eco, a KDE project focused on reducing software's environmental impact, has announced its Opt Green campaign to reduce e-waste:

Over the next two years, the "Opt Green" initiative will bring what KDE Eco has been doing for sustainable software directly to end users. A particular target group for the project is those whose consumer behavior is driven by principles related to the environment, and not just price or convenience: the "eco-consumers".

Through online and offline campaigns as well as installation workshops, we will demonstrate the power of Free Software to drive down resource and energy consumption, and keep devices in use for the lifespan of the hardware, not the software.

Our motto: The most environmentally-friendly device is the one you already own.

See the KDE Eco Get Involved page for more information on how to participate.

The "pidfdfs" virtual filesystem was added to the 6.9 kernel release as a way to export better information about running processes to user space. It replaced a previous implementation in a way that was, on its surface, fully compatible while adding a number of new capabilities. This transition, which was intended to be entirely invisible to existing applications, already ran into trouble in March, when a misunderstanding with SELinux caused systems with pidfdfs to fail to boot properly. That problem was quickly fixed, but it turns out that there was one more surprise in store, showing just how hard ABI compatibility can be at times.

The 2024 Kernel Maintainers Summit will happen on September 17 in Vienna, Austria; it is an invitation-only event for a small group to discuss important kernel-development problems. The call for proposals for this gathering has now been posted. One of the best ways to be invited to the event is to propose a topic that needs discussion in that forum. The deadline for proposals is June 18.

The developers of the Krita painting application are celebrating 25 years of development with a detailed history of the project.

A quarter century. That's how long we've been working on Krita. Well, what would become Krita. It started out as KImageShop, but that name was nuked by a now long-dead German lawyer. Then it was renamed to Krayon, and that name was also nuked. Then it was renamed to Krita, and that name stuck.

Security updates have been issued by AlmaLinux (.NET 7.0, .NET 8.0, 389-ds:1.4, ansible-core bug fix, enhancement, and, bind and dhcp, container-tools:rhel8, edk2, exempi, fence-agents, freeglut, frr, gdk-pixbuf2, ghostscript, git-lfs, glibc, gmp, go-toolset:rhel8, grafana, grub2, gstreamer1-plugins-bad-free, gstreamer1-plugins-base, gstreamer1-plugins-good, harfbuzz, httpd:2.4, Image builder components bug fix, enhancement and, kernel, kernel-rt, krb5, less, LibRaw, libsndfile, libssh, libtiff, libX11, libXpm, linux-firmware, motif, mutt, nghttp2, openssh, pam, pcp, pcs, perl-Convert-ASN1, perl-CPAN, perl:5.32, pki-core:10.6 and pki-deps:10.6, pmix, poppler, python-dns, python-jinja2, python-pillow, python27:2.7, python3, python3.11, python3.11-cryptography, python3.11-urllib3, python39:3.9 and python39-devel:3.9, qt5-qtbase, resource-agents, squashfs-tools, sssd, systemd, tigervnc, traceroute, vorbis-tools, webkit2gtk3, xorg-x11-server, xorg-x11-server-Xwayland, and zziplib), Debian (gst-plugins-base1.0), Fedora (cacti, cacti-spine, roundcubemail, and wireshark), Oracle (.NET 7.0, .NET 8.0, bind and dhcp, gdk-pixbuf2, git-lfs, glibc, grafana, krb5, pcp, python-dns, python3, sssd, tigervnc, xorg-x11-server, and xorg-x11-server-Xwayland), Red Hat (edk2, less, nghttp2, and ruby:3.0), SUSE (gstreamer-plugins-base, Java, kernel, and python-requests), and Ubuntu (ffmpeg, node-browserify-sign, postgresql-14, postgresql-15, postgresql-16, and python-pymysql).

While BPF may be most famous for its use in the Linux kernel, there is actually a growing effort to standardize BPF for use on other systems. These include eBPF for Windows, but also uBPF, rBPF, hBPF, bpftime, and others. Some hardware manufacturers are even considering integrating BPF directly into networking hardware. Dave Thaler led two sessions about all of the problems that cross-platform use inevitably brings and the current status of the standardization work at the 2024 Linux Storage, Filesystem, Memory Management, and BPF Summit.

A discussion of extensions to the statx() system call comes up frequently at the Linux Storage, Filesystem, Memory Management, and BPF Summit; this year's edition was no exception. Kent Overstreet led the first filesystem-only session at the summit on querying information about filesystems that have subvolumes and snapshots. While it was billed as a discussion on statx() additions, it ranged more widely over new APIs needed for modern filesystems.