Hyrum's Law states that any observable behavior of a system will eventually be depended upon by somebody. The kernel community is currently contending with a clear demonstration of that principle. The recent work to address some restartable-sequences performance problems in the 6.19 release maintained the documented API in all respects, but that was not enough; Google's TCMalloc library, as it turns out, violates the documented API, prevents other code from using restartable features, and breaks with 6.19. But the kernel's no-regressions rule is forcing developers to find a way to accommodate TCMalloc's behavior.

Version 16.1 of the GNU Compiler Collection (GCC) has been released.

The C++ frontend now defaults to the GNU C++20 dialect and the corresponding parts of the standard library are no longer experimental. Several C++26 features receive experimental support, including Reflection (-freflection), Contracts, expansion statements and std::simd.

Other changes include the introduction of an experimental compiler frontend for the Algol68 language, ability to output GCC diagnostics in HTML form, and more.

Greg Kroah-Hartman has released the 7.0.3, 6.18.26, 6.12.85, 6.6.137, 6.1.170, 5.15.204, and 5.10.254 stable kernels. The 7.0.3 and 6.18.26 kernels only contain fixes needed for Xen users; he advises that all users of the other kernel series must upgrade.

Security updates have been issued by AlmaLinux (buildah, firefox, gdk-pixbuf2, giflib, grafana, java-1.8.0-openjdk, java-21-openjdk, LibRaw, OpenEXR, PackageKit, pcs, python3.11, python3.12, python3.9, sudo, tigervnc, vim, xorg-x11-server, xorg-x11-server-Xwayland, yggdrasil, and yggdrasil-worker-package-manager), Debian (calibre, firefox-esr, and openjdk-17), Fedora (asterisk, binaryen, buildah, dokuwiki, lemonldap-ng, libexif, libgcrypt, miniupnpd, openvpn, podman, python3.9, rust-rpm-sequoia, skopeo, and xdg-dbus-proxy), Red Hat (buildah, gdk-pixbuf2, and nodejs:20), SUSE (dnsdist, libheif, openCryptoki, polkit, sed, and xen), and Ubuntu (linux-bluefield, python-marshmallow, and roundcube).

Inside this week's LWN.net Weekly Edition:

• Front: Famfs; Python packaging council; Zig concurrency; pages and folios; Strawberry music manager; 7.1 merge window.
• Briefs: GnuPG 2.5.19; Copy Fail; Plasma security; Fedora 44; Ubuntu 26.04; Niri 26.04; pip 26.1; RIP Seth Nickell; RIP Tomáš Kalibera; Quotes; ...
• Announcements: Newsletters, conferences, security updates, patches, and more.

Security analysis firm Xint has disclosed a security bug in the Linux kernel that allows for arbitrary 4-byte writes to the page cache, and which has been present since 2017. The vulnerability has been fixed in mainline kernels. A proof-of-concept script demonstrates how to use the flaw to corrupt a setuid binary, which works on multiple distributions, by requesting an AEAD-encrypted socket from user space and splicing a particular payload into it. A supplemental blog post gives more details about the discovery and remediation.

A core primitive underlying this bug is splice(): it transfers data between file descriptors and pipes without copying, passing page cache pages by reference. When a user splices a file into a pipe and then into an AF_ALG socket, the socket's input scatterlist holds direct references to the kernel's cached pages of that file. The pages are not duplicated; the scatterlist entries point at the same physical pages that back every read(), mmap(), and execve() of that file.

The Python packaging world now has a formal governance council, of the form described in PEP 772 ("Packaging Council governance process"), which was approved by the steering council on April 16. It has been over a year since the PEP was first proposed in February 2025 and it has undergone lengthy discussions in multiple postings to the Python discussion forum. The packaging council will have "broad authority over packaging standards, tools, and implementations"; it will consist of five members who will be elected in a vote that is likely to come in June—after PyCon US 2026 is held mid-May.

SUSE's Security Team has published a detailed blog post on their recent review of the Plasma Login Manager version 6.6.2, which was forked from the SDDM display manager.

While most of the code remains the same, the new upstream added a privileged D-Bus helper called plasmaloginauthhelper, which suffers from defense-in-depth security issues.

[...] Based on the high severity of the defense-in-depth issues shown in this report, our assessment is that there is effectively no separation between root and the plasmalogin service user account.

At this time there is no bugfix available by upstream, but a security fix is planned for the next Plasma release on May 12. We have not been involved in upstream's bugfix process so far and have no knowledge about the approach that will be taken to address the issues from this report.

Security updates have been issued by AlmaLinux (firefox, gdk-pixbuf2, java-17-openjdk, libxml2, python3, python3.11, python3.12, sudo, and webkit2gtk3), Debian (dnsdist, node-tar, pdns, pdns-recursor, and policykit-1), Fedora (chromium, edk2, and vim), Oracle (firefox, gdk-pixbuf2, go-toolset:rhel8, libpng12, LibRaw, libxml2, python, python3, python3.11, python3.12, python3.12-wheel, vim, webkit2gtk3, xorg-x11-server, xorg-x11-server-Xwayland, yggdrasil, and yggdrasil-worker-package-manager), Red Hat (container-tools:rhel8, delve, git-lfs, go-rpm-macros, grafana, grafana-pcp, osbuild-composer, and rhc), SUSE (bouncycastle, clamav, container-suseconnect, dovecot22, erlang, firefox, fontforge, freerdp2, ghostscript, giflib, gnome-remote-desktop, go1.25, go1.26, google-guest-agent, haproxy, ignition, ImageMagick, kernel, libcap, libpng16, libraw, librsvg, mariadb, openexr, pocketbase, protobuf, python-Pillow, python-requests, qemu, rust1.94, sudo, tomcat, tomcat10, tomcat11, webkit2gtk3, and xen), and Ubuntu (dotnet10, dovecot, linux-nvidia-lowlatency, node-follow-redirects, openssh, packagekit, python-cryptography, python-tornado, ruby-rack-session, ujson, and wheel).

LWN has received the sad news that Seth Nickell passed away, on April 16, from his father, Eric Nickell:

Many of you knew Seth from his work in the GNOME Usability Project, but his roots in that community trace back to his high school years. As a father of a high school junior, I remember being terrified when he flashed the hard drive of a computer he purchased for himself with this weird "Linux" thing. And I was a bit awed by the college application essay he wrote about open source and Linus Torvalds.

It was his interest in packet radio that drew him into working with the Linux AX.25 HOWTO as a high schooler, and from there to his focus on making the Linux desktop work for everyone.

The family plans to share news of a memorial at a later time. He will be deeply missed.

The Fedora Project has announced the release of Fedora Linux 44. There are "what's new" articles for Fedora Workstation, Fedora KDE Plasma Desktop, and Fedora Atomic Desktops. The Fedora Asahi Remix for Apple Silicon Macs, based on Fedora 44, is also available. See the Fedora Spins page for a full list of alternative desktop options.

Fedora Linux 44 Workstation ships with the latest GNOME release, GNOME 50. This comes with a long list of refinements to your desktop, including everything from accessibility to color management and remote desktop. Many of the applications that are installed by default on Fedora Workstation have also seen improvements, from Document Viewer to File Manager and Calendar. To learn more about these and other changes, you can read the GNOME 50 release notes.

KDE Plasma Desktop: If you are a KDE user, you should also notice a couple of very obvious changes. Fedora KDE Plasma Desktop 44 is based on the latest Plasma 6.6, which includes the new Plasma Login Manager and Plasma Setup to provide a more cohesive and integrated experience from the moment the computer is powered on for the first time. The installation process has been simplified, enabling you to easily set up Fedora KDE Plasma Desktop for a computer for a friend or a loved one.

The release notes include important changes between Fedora 43 and Fedora 44 for desktop users, developers, and system administrators.

There are dozens of music-player applications for Linux; the options range from bare-bones programs that only play local files to full-blown music-management projects with a full suite of tools for managing (and playing) a music collection. Strawberry is in the latter category; it has a bumper crop of features, including smart playlists, support for editing music metadata tags, the ability to organize music files, and more.

We have received the sad news that Tomáš Kalibera, a member of the R Project core team, has passed away after a short illness.

A friend who knew him well wrote to me: he was very happy, and his work fulfilled him. That is, perhaps, the best thing one can say about a life in open source — that the work mattered, that it reached millions, and that the person who did it found meaning in it.

Kalibera was mentioned in this 2019 article about C programs passing strings to Fortran subroutines. He will be greatly missed.

FOSDEM's organizers have announced that all of the video recordings "worth publishing" from FOSDEM 2026 are now available.

Videos are linked from the individual schedule pages for the talks and the full schedule page. They are also available, organised by room, at video.fosdem.org/2026.

LWN's coverage of talks from FOSDEM 2026 can be found on our conference index.

Security updates have been issued by Debian (openjdk-21 and webkit2gtk), Fedora (botan3, chromium, cockpit, firefox, flatpak, gum, libarchive, libcoap, mingw-python3, ngtcp2, nss, openssh, openssl, openvpn, PackageKit, python3-docs, python3.11, python3.12, python3.13, python3.14, vim, and xrdp), Oracle (firefox, gdk-pixbuf2, java-1.8.0-openjdk, java-21-openjdk, python3.12, python3.9, sudo, and tigervnc), Red Hat (tigervnc and xorg-x11-server-Xwayland), Slackware (mpg123 and proftpd), SUSE (emacs, firefox, fontforge, freeciv, freerdp, libngtcp2-16, libsystemd0, and strongswan), and Ubuntu (authd, clamav, glance, haproxy, jq, lcms2, nginx, nltk, ntfs-3g, packagekit, pillow, strongswan, and vim).

Version 26.1 of the pip package installer for Python has been released. Richard Si has published a blog post that looks at some of the highlights of 26.1 including dependency cooldowns, experimental support for pylock (pylock.toml) files, and resolver improvements that will move pip closer to the goal of removing its legacy resolver. The release also includes several security fixes and drops support for Python 3.9.

By the time Linus Torvalds released 7.1-rc1 and closed the 7.1 merge window, 12,996 non-merge changesets had been pulled into the mainline repository; just over 9,000 of those arrived after the first-half summary was written. These changes were more driver-oriented than those seen earlier, but still also included many new features across the kernel as a whole.

Greg Kroah-Hartman has announced the release of the 7.0.2, 6.18.25, 6.12.84, and 6.6.136 stable kernels. As usual, each contains important fixes throughout; users are advised to upgrade.

David Steele, maintainer of the popular pgBackRest backup and restore project for PostgreSQL, has archived the project and announced that it is no longer being maintained.

After a lot of thought, I have decided to stop working on pgBackRest. I did not come to this decision lightly. pgBackRest has been my passion project for the last thirteen years, and I was fortunate to have corporate sponsorship for much of this time, but there were also many late nights and weekends as I worked to make pgBackRest the project it is today, aided by numerous contributors. Every open-source developer knows exactly what I mean and how much of your life gets devoted to a special project.

Since Crunchy Data was sold, I have been maintaining pgBackRest and looking for a position that would allow me to continue the work, but so far I have not been successful. Likewise, my efforts to secure sponsorship have also fallen far short of what I need to make the project viable.

Version 0.16.0 of the Zig programming language was recently announced, and with it an expanded version of the new Io interface that we covered in December. The new interface is based on an idea called structured concurrency that makes writing correct concurrent applications easier. Zig's implementation of the idea is more explicit and verbose than other languages, however, which could offer an opportunity to explore the consequences of different designs.