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The kernel project makes a strong promise to its users: the kernel ABI will not be changed in ways that break user-space code. The occasional failure notwithstanding, kernel developers do try to live up to that promise. They are handicapped by one little problem, though: there is no description of what the kernel ABI is, and no comprehensive way to test whether a given change breaks it. The kernel API specification framework proposed (in its second revision) by Sasha Levin addresses some of those concerns, but the solution is incomplete and does not come for free.

Security updates have been issued by AlmaLinux (.NET 9.0, aardvark-dns, apache-commons-beanutils, bootc, buildah, corosync, delve and golang, exiv2, expat, firefox, ghostscript, git, git-lfs, gnutls, grafana, grafana-pcp, grub2, gstreamer1, gstreamer1-plugins-bad-free, gstreamer1-plugins-ugly-free, and gstreamer1-rtsp-server, gstreamer1-plugins-base, gstreamer1-plugins-good, gvisor-tap-vsock, iptraf-ng, java-21-openjdk, kernel, keylime-agent-rust, krb5, libarchive, libblockdev, libsoup3, libtasn1, libvpx, libxslt, microcode_ctl, mod_auth_openidc, nodejs22, nodejs:20, openjpeg2, osbuild and osbuild-composer, perl-FCGI, perl-Module-ScanDeps, perl-YAML-LibYAML, php, php:8.2, php:8.3, podman, protobuf, python-jinja2, python-requests, python3.11, python3.12, python3.12-cryptography, python3.9, rpm-ostree, rsync, rust-bootupd, skopeo, thunderbird, tigervnc, tomcat, tomcat9, webkit2gtk3, xdg-utils, xorg-x11-server, and xorg-x11-server-Xwayland), Debian (ring), Mageia (libarchive and rootcerts, nss & firefox), Oracle (.NET 9.0, corosync, firefox, osbuild-composer, pam, python3, python3.11, python3.12, python3.9, skopeo, sudo, and thunderbird), Red Hat (microcode_ctl, pam, php, thunderbird, tigervnc, xorg-x11-server, xorg-x11-server and xorg-x11-server-Xwayland, and xorg-x11-server-Xwayland), SUSE (clamav, icu, libgepub, libsoup, python-requests, tomcat, and xorg-x11-server), and Ubuntu (clamav, logback, mongo-c-driver, pcs, and python-flask-cors).

Inside this week's LWN.net Weekly Edition:

• Front: Kernel features from Python; i686 in Fedora; Kernel development with LLMs; Rust drivers; Load balancing with machine learning; Transparent huge pages.
• Briefs: Bcachefs removal; Coccinelle for Rust; Netdev Foundation; Oracle Linux 10; GNU HHIS 5.0; Rust 1.88.0; Quotes; ...
• Announcements: Newsletters, conferences, security updates, patches, and more.

Debian's Bananas team has put out a call for people with Apple M1 or M2 systems to help test Debian on those machines:

The Bananas Team has set up an installer at with images for GNOME, KDE and console installations. While we'd like to build an actual Debian installer sooner or later (we may need a heads-up from the Debian Images team for that), at this time we only provide an asahi-type installer, which installs both the "bootloader" and the OS partitions to disk from the network (as opposed to only installing the bootloader and then letting you install Debian using a d-i USB stick). We haven't forked Trixie from Testing yet, so what you'll get is Debian Testing quite deep into the freeze.

The Netdev Foundation, which is "a user-led effort under the supervision of the Linux Foundation, focused on financially supporting Linux networking development", has announced its existence.

The initial motivation was to move the NIPA testing outside of Meta, so that more people can help and contribute. But there should be sufficient budget to sponsor more projects.

(NIPA is Netdev Infrastructure for Patch Automation).

Every release of the Linux kernel has lots of new features, many of which are accessible from user space. Usually, though, the GNU C Library (glibc) and tools that access the Linux user-space API lag behind the kernel releases. Geoffrey Thomas showed how Python programs can access these new kernel features as soon as the kernel is released in his "What's New in the Linux Kernel... from Python" talk at PyCon US 2025. While he had two examples of accessing new kernel features, the real goal of the talk was to demonstrate how to go about connecting Python to the Linux kernel.

The copyleft-next project is an effort to develop a next-generation copyleft license; it was covered here back in 2013 (as well as in 2015 and 2021). The project has stalled in recent years, but now Richard Fontana and Bradley Kuhn have announced a new effort to push copyleft-next forward:

Today, GPLv3 turns exactly 18 years old. This month, GPLv2 turned 34 years old. These are both great licenses and we love them. Nevertheless, at least once in a generation, FOSS needs a new approach to strong copyleft.

Security updates have been issued by AlmaLinux (apache-commons-beanutils, firefox, kea, kernel, kernel-rt, libblockdev, libvpx, pam, python-setuptools, python3, python3.11, python3.12, python3.9, and sudo), Debian (chromium), Gentoo (sudo), Oracle (.NET 8.0, buildah, firefox, freerdp, golang-github-openprinting-ipp-usb, grafana, grafana-pcp, gvisor-tap-vsock, libsoup3, mod_proxy_cluster, perl-FCGI, podman, python-setuptools, qt6-qtbase, skopeo, sudo, and thunderbird), Slackware (mozilla), SUSE (redis, runc, xorg-x11-server, and xwayland), and Ubuntu (composer, linux, linux-aws, linux-aws-6.8, linux-gcp, linux-gcp-6.8, linux-gke, linux-gkeop, linux-lowlatency, linux-lowlatency-hwe-6.8, linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency, linux-oem-6.8, linux-oracle, linux-oracle-6.8, linux-raspi, linux, linux-aws, linux-gcp, linux-gcp-5.15, linux-gke, linux-gkeop, linux-hwe-5.15, linux-ibm, linux-kvm, linux-lowlatency, linux-lowlatency-hwe-5.15, linux-nvidia, linux-oracle, linux-oracle-5.15, linux, linux-aws, linux-gcp, linux-gcp-6.11, linux-hwe-6.11, linux-oracle, linux-raspi, linux-realtime, linux, linux-aws, linux-lts-xenial, linux, linux-gcp, linux-raspi, linux-realtime, linux-fips, linux-fips, linux-aws-fips, linux-gcp-fips, linux-realtime, and linux-realtime, linux-raspi-realtime).

Version 5.0 of the GNU Health Hospital Information System has been released. This project, working to support medical offices, shows just how far the free-software effort can reach. Changes in this release include improved reporting and analytics, more comprehensive handling of many types of patient information, a reworked medical-imaging subsystem, better insurance and billing functionality, and more.

Transparent huge pages (THPs) are, theoretically, supposed to allow processes to benefit from larger page sizes without changes to their code. This does work, but the performance impacts from THPs are not always a benefit, so system administrators with specific knowledge of their workloads may want the ability to fine-tune THPs to the application. On May 15, Usama Arif shared a patch set that would add a prctl() option for setting THP defaults for a process; that patch set has sparked discussion about whether such a setting is a good fit for prctl(), and what alternative designs may work instead.

The extensible scheduler class ("sched_ext") allows the loading of a custom CPU scheduler into the kernel as a set of BPF functions; it was merged for the 6.12 kernel release. Since then, sched_ext has enabled a wide range of experimentation with scheduling algorithms. At the 2025 Open Source Summit North America, Ching-Chun ("Jim") Huang presented work that has been done to apply (local) machine learning to the problem of scheduling processes on complex systems.

The OsmAnd map and navigation app project recently celebrated its 15th anniversary.

All these 15 years can be roughly divided into three stages. For the first five years, we built the very basic functionality—offline maps and navigation that just worked. Over the next five years, we transformed OsmAnd into a full-fledged application with plugins, extensive settings, and professional tools. We dedicated the third five-year period to deep internal work: completely rewriting and improving key components like the rendering engine and routing algorithms.

Now, a new, fourth stage begins. We have reached functional maturity, and our main goal for the near future is to polish what we've already built. We will focus on stability, speed, and consolidation. User expectations are growing, and what was once considered normal must now be flawless.

(Thanks to Paul Wise).

Security updates have been issued by AlmaLinux (delve, emacs, gimp, gimp:2.8, glibc, idm:DL1, ipa, iputils, kernel, krb5, libarchive, libblockdev, libxml2, mod_proxy_cluster, osbuild-composer, pam, perl-File-Find-Rule, perl-YAML-LibYAML, qt5-qtbase, weldr-client, xorg-x11-server and xorg-x11-server-Xwayland, and xorg-x11-server-Xwayland), Debian (mbedtls and sudo), Oracle (.NET 8.0, delve, delve, golang, firefox, ghostscript, glibc, golang, grafana, iputils, kernel, krb5, libarchive, libblockdev, nodejs22, ruby, thunderbird, tomcat, tomcat9, unbound, and wireshark), Red Hat (glibc and mod_auth_openidc), Slackware (sudo), SUSE (gpg2, ImageMagick, iputils, jakarta-commons-fileupload, kernel, libblockdev, libsoup, open-vm-tools, pam, python-tornado6, screen, sudo, and xwayland), and Ubuntu (linux, linux-aws, linux-gcp, linux-gcp-6.11, linux-hwe-6.11, linux-oracle, linux-raspi, linux-realtime, linux-gcp, linux-gcp-6.8, linux-hwe-5.4, linux-oem-6.11, and sudo).

A change proposal to end support for 32-bit x86 (i686) applications on the x86_64 architecture with the Fedora 44 release has been withdrawn after significant pushback. As proposed, the change could have had a significant impact on gamers, compiler development, and the Bazzite project, which uses Fedora as a base for a gaming-focused distribution. While i686 gets a reprieve for now, the question still lingers: who is going to keep the necessary i686 packages in working order when few upstream maintainers or volunteer packagers care about the architecture?

Security updates have been issued by AlmaLinux (mod_proxy_cluster), Debian (catdoc, chromium, nagvis, and sudo), Fedora (chromium, gum, kubernetes1.32, moodle, podman, python3-docs, python3.13, salt, and tigervnc), Mageia (x11-server, x11-server-xwayland & tigervnc), Oracle (apache-commons-beanutils, exiv2, expat, firefox, git, git-lfs, gstreamer1-plugins-bad-free, ipa, java-21-openjdk, kea, kernel, libarchive, libblockdev, libsoup3, libvpx, libxslt, mod_auth_openidc, nodejs22, osbuild-composer, perl, perl-File-Find-Rule, php, python-jinja2, python-tornado, sqlite, thunderbird, valkey, varnish, weldr-client, xorg-x11-server-Xwayland, xz, and yggdrasil), Red Hat (apache-commons-beanutils, javapackages-tools:201801, kernel, and python3.11), SUSE (apache-commons-fileupload, gimp, glib2, himmelblau, nvidia-open-driver-G06-signed, sqlite3, thunderbird, yelp, and yelp-xsl), and Ubuntu (samba).

Linus has released 6.16-rc4 for testing. "Despite a fairly large merge window, things continue to look fairly calm on the rc front".

In 2023, Fujita Tomonori wrote a Rust version of the existing driver for the Asix AX88796B embedded Ethernet controller. At slightly more than 100 lines, it's about as simple as a driver can be, and therefore is a useful touchstone for the differences between writing Rust and C in the kernel. Looking at the Rust syntax, types, and APIs used by the driver and contrasting them with the C version will help illustrate those differences.

The history of the bcachefs filesystem in the kernel has been turbulent, most recently with Linus Torvalds refusing a pull request for the 6.16-rc3 release. Torvalds has now pulled the code in question, but also said:

I think we'll be parting ways in the 6.17 merge window.

You made it very clear that I can't even question any bug-fixes and I should just pull anything and everything.

Honestly, at that point, I don't really feel comfortable being involved at all, and the only thing we both seemed to really fundamentally agree on in that discussion was "we're done".

Bcachefs developer Kent Overstreet has his own view of the situation. Both Torvalds and Overstreet refer to a seemingly private conversation where the pull request (and other topics) were discussed.

Kernel versions 6.15.4, 6.12.35, 6.6.95, 6.1.142, 5.15.186, 5.10.239, and 5.4.295 have all been released.

Security updates have been issued by Debian (freeradius and icu), Fedora (clamav, glow, libssh, perl-Crypt-OpenSSL-RSA, perl-CryptX, podman, trafficserver, and xorg-x11-server), Mageia (gdk-pixbuf2.0 and thunderbird), Red Hat (osbuild-composer and weldr-client), SUSE (afterburn, google-osconfig-agent, libblockdev, pam, python-tornado6, screen, and yelp-xsl), and Ubuntu (libxslt and python-pip).