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The first installment in this series introduced several data structures in the kernel's swap subsystem and described work to replace some of those with a new "swap table" structure. The work did not stop there, though; there is more modernization of the swap subsystem queued for an upcoming development cycle, and even more for multiple kernel releases after that. Once that work is done, the swap subsystem will be both simpler and faster than it is now.

Security updates have been issued by AlmaLinux (brotli, curl, kernel, python-wheel, and python3.12), Debian (containerd), Fedora (gnupg2, pgadmin4, phpunit10, phpunit11, phpunit12, phpunit8, phpunit9, and yarnpkg), Mageia (expat), Oracle (qemu-kvm and util-linux), Red Hat (kernel, kernel-rt, opentelemetry-collector, and python3.12-wheel), SUSE (abseil-cpp, dpdk, freerdp, glib2, ImageMagick, java-11-openj9, java-17-openj9, java-1_8_0-ibm, java-1_8_0-openj9, java-1_8_0-openjdk, java-21-openj9, kernel, libsoup, libsoup-3_0-0, openssl-3, patch, python-Django, rekor, rizin, udisks2, and xrdp), and Ubuntu (gh, linux, linux-aws, linux-azure, linux-azure-5.15, linux-gcp, linux-gke, linux-gkeop, linux-hwe-5.15, linux-ibm, linux-ibm-5.15, linux-intel-iotg, linux-intel-iotg-5.15, linux-kvm, linux-lowlatency, linux-lowlatency-hwe-5.15, linux-nvidia, linux-nvidia-tegra, linux-nvidia-tegra-5.15, linux-oracle, linux-raspi, linux, linux-aws, linux-azure, linux-gcp, linux-oem-6.17, linux-oracle, linux-raspi, linux-realtime, linux, linux-gke, linux-gkeop, linux-hwe-6.8, linux-oracle, linux-oracle-6.8, linux-raspi, linux-fips, linux-aws-fips, linux-azure-fips, linux-gcp-fips, linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency, linux-realtime, linux-intel-iot-realtime, and linux-realtime, linux-realtime-6.8, linux-raspi-realtime).

Inside this week's LWN.net Weekly Edition:

• Front: Sigil; Eurydice; Sub-schedulers for sched_ext; Swap table; Futex robust lists; Tyr.
• Briefs: openSUSE governance; Git 2.53.0; LibreOffice 26.2; Open Source Award; Quotes; ...
• Announcements: Newsletters, conferences, security updates, patches, and more.

The robust futex kernel API is a way for a user-space program to ensure that the locks it holds are properly cleaned up when it exits. But the API suffers from a number of different problems, as André Almeida described in a session in the "Gaming on Linux" microconference at the 2025 Linux Plumbers Conference in Tokyo. He had some ideas for a new API that would solve many of those problems, which he wanted to discuss with attendees; there is a difficult-to-trigger race condition that he wanted to talk about too.

Creating an ebook in EPUB format is easy, for certain values of "easy". All one really needs is a text editor, a few command-line utilities; also needed is a working knowledge of XHTML, CSS, along with an understanding of the format's structure and required boilerplate. Creating a well-formatted and attractive ebook is a bit harder. However, it can be made easier with an application custom-made for the purpose. Sigil is an EPUB editor that provides the tooling authors and publishers may be looking for.

Version 26.2 of the LibreOffice office suite has been released. LibreOffice 26.2 is focused on improvements that make a difference in daily work and brings better performance, smoother interaction with complex documents and improved compatibility with files created in other office software. Whether you're writing reports, managing spreadsheets, or preparing presentations, the experience feels more responsive and reliable.

LibreOffice has always been about giving users control. LibreOffice 26.2 continues that tradition by strengthening support for open document standards, and ensuring long-term access to your files, without subscriptions, license restrictions, or data collection. Your documents stay yours – forever.

More information can be found in the release notes for LibreOffice 26.2.

Security updates have been issued by Debian (thunderbird), Fedora (openqa, os-autoinst, python-jupytext, python-python-multipart, rust-sequoia-keystore-server, rust-sequoia-octopus-librnp, rust-sequoia-sq, rust-sequoia-sqv, and xen), Oracle (curl, kernel, net-snmp, python3, and python3.12), Red Hat (container-tools:rhel8, fence-agents, golang, golang-github-openprinting-ipp-usb, grafana, grafana-pcp, opentelemetry-collector, podman, python-s3transfer, python-wheel, and resource-agents), SUSE (alloy, chromium, cockpit-podman, cockpit-subscriptions, dpdk, elemental-register, elemental-toolkit, glib2, glibc, gpg2, ImageMagick, imagemagick, jasper, java-17-openjdk, java-21-openjdk, kernel, libheif, libmlt++, libpng16, libsodium, libsoup, libvirt, openssl-3, openvpn, php8, postgresql16, postgresql17 and postgresql18, protobuf, python-FontTools, python-fonttools, python-h2, python-python-multipart, python-urllib3, python-wheel, python311-PyNaCl, trivy, ucode-amd, udisks2, unbound, util-linux, wireshark, and xkbcomp), and Ubuntu (emacs, freerdp2, glibc, imagemagick, mysql-8.0, pagure, python-django, python-filelock, python-internetarchive, and python-keystonemiddleware).

The team behind Tyr started 2025 with little to show in our quest to produce a Rust GPU driver for Arm Mali hardware, and by the end of the year, we were able to play SuperTuxKart (a 3D open-source racing game) at the Linux Plumbers Conference (LPC). Our prototype was a joint effort between Arm, Collabora, and Google; it ran well for the duration of the event, and the performance was more than adequate for players. Thankfully, we picked up steam at precisely the right moment: Dave Airlie just announced in the Maintainers Summit that the DRM subsystem is only "about a year away" from disallowing new drivers written in C and requiring the use of Rust. Now it is time to lay out a possible roadmap for 2026 in order to upstream all of this work.

Security updates have been issued by AlmaLinux (fence-agents, gcc-toolset-15-binutils, golang-github-openprinting-ipp-usb, iperf3, kernel, kernel-rt, openssl, osbuild-composer, php:8.2, python3, util-linux, and wireshark), Debian (clamav and xrdp), Fedora (gimp and openttd), Mageia (docker-containerd), Oracle (gimp:2.8, golang-github-openprinting-ipp-usb, grafana-pcp, image-builder, iperf3, kernel, openssl, osbuild-composer, php, php:8.2, php:8.3, python3.9, util-linux, and wireshark), SUSE (cockpit-subscriptions, elemental-register, elemental-toolkit, glibc, gpg2, logback, openssl-1_1, python-urllib3, ucode-amd, and unbound), and Ubuntu (inetutils, libpng1.6, mysql-8.0, mysql-8.4, openjdk-17, openjdk-17-crac, openjdk-21, openjdk-21-crac, openjdk-25, openjdk-25-crac, openjdk-8, openjdk-lts, and thunderbird).

Version 2.53.0 of the Git source-code management system has been released. Changes include documentation for the Git data model, the ability to choose the diff algorithm to use with git blame, a new white-space error class, and more; see the announcement for details.

The kernel's swap subsystem is a complex and often unloved beast. It is also a critical component in the memory-management subsystem and has a significant impact on the performance of the system as a whole. At the 2025 Linux Storage, Filesystem, Memory-Management and BPF Summit, Kairui Song outlined a plan to simplify and optimize the kernel's swap code. A first installment of that work, written with help from Chris Li, was merged for the 6.18 release. This article will catch up with the 6.18 work, setting the stage for a future look at the changes that are yet to be merged.

Security updates have been issued by AlmaLinux (iperf3, kernel, and php), Debian (ceph, pillow, pyasn1, python-django, and python-tornado), Fedora (bind9-next, cef, chromium, fontforge, java-21-openjdk, java-25-openjdk, java-latest-openjdk, mingw-python-urllib3, mingw-python-wheel, nodejs20, nodejs22, nodejs24, opencc, openssl, python-wheel, and qownnotes), Red Hat (binutils, gcc-toolset-13-binutils, gcc-toolset-14-binutils, gcc-toolset-15-binutils, java-1.8.0-openjdk, and java-25-openjdk), Slackware (expat), SUSE (bind, cacti, cacti-spine, chromedriver, chromium, dirmngr, fontforge-20251009, glib2, golang-github-prometheus-prometheus, govulncheck-vulndb, icinga2, ImageMagick, kernel, logback, openCryptoki, openssl-1_1, python311-djangorestframework, python311-pypdf, python314, python315, qemu, and xen), and Ubuntu (linux, linux-aws, linux-aws-5.4, linux-gcp, linux-gcp-5.4, linux-hwe-5.4, linux-ibm, linux-ibm-5.4, linux-iot, linux-kvm and linux-aws-fips, linux-fips, linux-gcp-fips).

The 6.19-rc8 kernel prepatch is out for testing. "So things all look good, and unless something odd happens we'll have a final 6.19 next weekend."

A few years ago, the only way to compile Rust code was using the rustc compiler with LLVM as a backend. Since then, several projects, including Mutabah's Rust Compiler (mrustc), GCC's Rust support (gccrs), rust_codegen_gcc, and Cranelift have made enormous progress on diversifying Rust's compiler implementations. The most recent such project, Eurydice, has a more ambitious goal: converting Rust code to clean C code. This is especially useful in high-assurance software, where existing verification and compliance tools expect C. Until such tools can be updated to work with Rust, Eurydice could provide a smoother transition for these projects, as well as a stepping-stone for environments that have a C compiler but no working Rust compiler. Eurydice has been used to compile some post-quantum-cryptography routines from Rust to C, for example.

Daniel Stenberg, the recipient of last year's Award for Excellence in Open Source from the European Open Source Academy, presented that award to this year's recipient: Greg Kroah-Hartman.

It's impossible to overstate the importance of the work Greg has done on Linux. In software, innovation grabs headlines, but stability saves lives and livelihoods. Every Android phone, every web server, every critical system running Linux depends on Greg's meticulous work. He ensures that when hospitals, banks, governments, and individuals rely on Linux, it doesn't fail them. His work represents the highest form of service: unglamorous, relentless, and essential.

The 6.18.8, 6.12.68, and 6.6.122 stable kernel updates have been released; each contains another set of important fixes.

Security updates have been issued by AlmaLinux (curl, gimp:2.8, glibc, grafana, grafana-pcp, kernel, osbuild-composer, php:8.3, python-urllib3, python3.11, and python3.12), Debian (chromium), Mageia (ceph, gpsd, libxml2, openjdk, openssl, and xen), SUSE (abseil-cpp, assertj-core, coredns, freerdp, java-11-openjdk, java-25-openjdk, libxml2, openssl-1_0_0, openssl-1_1, python, python-filelock, and python311-sse-starlette), and Ubuntu (kernel, linux, linux-aws, linux-aws-hwe, linux-hwe, linux-kvm, linux-oracle, linux, linux-aws, linux-kvm, linux-lts-xenial, linux-aws-fips, linux-fips, linux-fips, and texlive-bin).

Jeff Mahoney, who holds a vice-president position at SUSE, has posted a detailed proposal for improving the governance of the openSUSE project.

It's meant to be a way to move from governance by volume or persistence toward governance by legitimacy, transparency, and process - so that disagreements can be resolved fairly and the project can keep moving forward. Introducing structure and predictability means it easier for newcomers to the project to participate without needing to understand decades of accumulated history. It potentially could provide a clearer roadmap for developers to find a place to contribute.

The stated purpose is to start a discussion; this is openSUSE, so he is likely to succeed.

The extensible scheduler class (sched_ext) allows the installation of a custom CPU scheduler built as a set of BPF programs. Its merging for the 6.12 kernel release moved the kernel away from the "one scheduler fits all" approach that had been taken until then; now any system can have its own scheduler optimized for its workloads. Within any given machine, though, it's still "one scheduler fits all"; only one scheduler can be loaded for the system as a whole. The sched_ext sub-scheduler patch series from Tejun Heo aims to change that situation by allowing multiple CPU schedulers to run on a single system.

Security updates have been issued by AlmaLinux (java-25-openjdk, openssl, and python3.9), Debian (gimp, libmatio, pyasn1, and python-django), Fedora (perl-HarfBuzz-Shaper, python-tinycss2, and weasyprint), Mageia (glib2.0), Oracle (curl, fence-agents, gcc-toolset-15-binutils, glibc, grafana, java-1.8.0-openjdk, kernel, mariadb, osbuild-composer, perl, php:8.2, python-urllib3, python3.11, python3.11-urllib3, python3.12, and python3.12-urllib3), SUSE (alloy, avahi, bind, buildah, busybox, container-suseconnect, coredns, gdk-pixbuf, gimp, go1.24, go1.24-openssl, go1.25, helm, kernel, kubernetes, libheif, libpcap, libpng16, openjpeg2, openssl-1_0_0, openssl-1_1, openssl-3, php8, python-jaraco.context, python-marshmallow, python-pyasn1, python-urllib3, python-virtualenv, python311, python313, rabbitmq-server, xen, zli, and zot-registry), and Ubuntu (containerd, containerd-app and wlc).