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Working on the kernel can be a challenging task but, for many, configuring a kernel build can be the largest obstacle to getting started. The kernel has thousands of configuration options; many of those, if set incorrectly, will result in a kernel that does not work on the target system. The key to helping users with complex configuration problems is to provide reasonable defaults but, in the kernel community, there is currently little consensus around what those defaults should be.

Security updates have been issued by Debian (dns-root-data and xorg-server), Fedora (glibc, mingw-glib2, and optipng), Red Hat (iputils, kernel, kernel-rt, krb5, libarchive, mod_auth_openidc, mod_proxy_cluster, and xorg-x11-server-Xwayland), SUSE (python313), and Ubuntu (fig2dev, gnuplot, gss-ntlmssp, linux, linux-gcp, linux-gke, linux-gkeop, linux-ibm, linux-kvm, linux-lowlatency, linux-nvidia, linux-nvidia-tegra, linux-nvidia-tegra-igx, linux-oracle, linux-aws-5.15, linux-gcp-5.15, linux-ibm-5.15, linux-lowlatency-hwe-5.15, linux-oracle-5.15, linux-aws-fips, linux-fips, linux-gcp-fips, linux-hwe-5.15, and linux-intel-iot-realtime, linux-realtime).

KDE contributor Nate Graham recently wrote about the KDE Project's plans for Plasma's X11 session. He notes that the project will continue to ensure that Plasma "continues to compile and deploy on X11" and isn't horribly broken. Major regressions will probably be fixed, eventually, but the writing is on the wall:

X11's upstream development has dropped off significantly in recent years, and X11 isn't able to perform up to the standards of what people expect today with respect to HDR, 10 bits-per-color monitors, other fancy monitor features, multi-monitor setups (especially with mixed DPIs or refresh rates), multi-GPU setups, screen tearing, security, crash robustness, input handling, and more.

As for when Plasma will drop support for X11? There's currently no firm timeline for this, and I certainly don't expect it to happen in the next year, or even the next two years. But that's just a guess; it depends on how quickly we implement everything on https://community.kde.org/Plasma/Wayland_Known_Significant_Issues. Our plan is to handle everything on that page such that even the most hardcore X11 user doesn't notice anything missing when they move to Wayland.

The postmarketOS project, which creates a Linux distribution for mobile devices, announced it was working on adding a version with systemd last March. That day has arrived with the announcement of version 25.06:

We considered supporting an upgrade from OpenRC to systemd in our upgrade script, but then decided against it as such an upgrade path might introduce its own bugs and we would rather spend the time improving other parts of postmarketOS. So for this one-time scenario we ask you to please reinstall postmarketOS to get from OpenRC to systemd. Thank you for your understanding!

Adrian Vovk, a GNOME contributor and member of its release team, recently announced in a blog post that GNOME would be adding new dependencies on systemd, and soon. The idea is to shed GNOME's homegrown service manager in favor of using systemd, and to improve GNOME's ability to run concurrent user sessions. However, the move is also going to throw a spanner in the works for the BSDs and Linux distributions without systemd when the changes take effect in the GNOME 49 release that is set for September.

The Collabora blog has a summary, written by Nicolas Dufresne, about the Linux Media Summit held on May 13 in Nice, France. It was co-located with the Embedded Recipes conference and had sessions on stateless video encoders, camera support, staging drivers, memory accounting, and a multi-committer model for the media subsystem. "Our largest Media Summit to date brought together around 20 engaged participants. Engagement was strong, marked by thoughtful questions and lively discussions."

Security updates have been issued by AlmaLinux (libblockdev and open-vm-tools), Debian (debian-security-support, gdk-pixbuf, konsole, and node-send), Fedora (apache-commons-beanutils, chromium, clamav, dotnet9.0, libblockdev, mediawiki, mingw-python-setuptools, pam, perl-File-Find-Rule, python-pycares, python-setuptools, spdlog, udisks2, and xorg-x11-server-Xwayland), Mageia (chromium-browser-stable), Oracle (apache-commons-beanutils, container-tools:ol8, gimp:2.8, idm:DL1, perl-FCGI:0.78, and postgresql), Red Hat (container-tools:rhel8, delve, git-lfs, go-toolset:rhel8, grafana, kernel, mod_auth_openidc, and spice-client-win), SUSE (apache-commons-beanutils, apache2-mod_security2, distribution, gstreamer-plugins-good, icu, ignition, perl, python310, python311, python312, and python39), and Ubuntu (apache-log4j1.2 and botan).

Linus has released 6.16-rc3 for testing. "So rc2 was smaller than usual, but rc3 seems to be right in the usual ballpark for this time, so everything looks entirely normal."

The Linux kernel is seeing a steady accumulation of Rust code. As it becomes more prevalent, maintainers may want to know how to read, review, and test the Rust code that relates to their areas of expertise. Just as kernel C code is different from user-space C code, so too is kernel Rust code somewhat different from user-space Rust code. That fact makes Rust's extensive documentation of less use than it otherwise would be, and means that potential contributors with user-space experience will need some additional instruction. This article is the first in a multi-part series aimed at helping existing kernel contributors become familiar with Rust, and helping existing Rust programmers become familiar with what the kernel does differently from the typical Rust project.

A new filesystem was the topic of a session led by Zach Brown at the 2025 Linux Storage, Filesystem, Memory Management, and BPF Summit (LSFMM+BPF). The ngnfs filesystem is not a "next generation" NFS, as might be guessed from the name; Brown said that he did not think about that linkage ("I hate naming so much") until it was pointed out to him by Chuck Lever in an email. It is, instead, a filesystem for enormous data sets that are mostly stored offline.

Debian's long-awaited tag2upload service is now ready for Debian maintainers to use in some circumstances. Tag2upload makes it easier for maintainers to upload packages, by allowing them to push a signed Git commit that will automatically be picked up and built, instead of pushing a build from their local machine. LWN covered the discussion around the service in July of last year. With the timing of its readiness, it's likely to become more useful once Debian 13 ("trixie") is released.

Be very aware of the freeze! Do not just upload to unstable as your first test! Uploads to unstable, targeting trixie, can be done with tag2upload - but in most cases you will probably want to upload the same package to experimental first.

Security updates have been issued by SUSE (apache2-mod_security2, augeas, ghc-pandoc, gstreamer, ignition, kernel, libblockdev, libxml2, nodejs20, openssl-3, pam_pkcs11, perl, python3, systemd, ucode-intel, webkit2gtk3, and xen) and Ubuntu (linux, linux-aws, linux-aws-5.4, linux-azure, linux-gcp, linux-gcp-5.4, linux-ibm, linux-ibm-5.4, linux-kvm, linux-oracle, linux-oracle-5.4, linux-xilinx-zynqmp, linux-aws-fips, linux-gcp-fips, python3.13, python3.12, and roundcube).

Born from research at the Southern University of Science and Technology (SUSTech) in Shenzen, China, Asterinas is a new Linux-ABI-compatible kernel project written in Rust, based on what the authors call a "framekernel architecture". The project overlaps somewhat with the goals of the Rust for Linux project, but approaches the problem space from a different direction by trying to get the best from both monolithic and microkernel designs.

Greg Kroah-Hartman has announced the release of the 6.15.3, 6.12.34, and 6.6.94 stable kernels. Each contains a relatively large number of important fixes throughout the kernel tree.

Security updates have been issued by AlmaLinux (gvisor-tap-vsock), Debian (activemq and chromium), Fedora (kea, python-django4.2, python-django5, python-setuptools, and rust-git-interactive-rebase-tool), Oracle (ipa and kernel), Red Hat (buildah, container-tools:rhel8, containernetworking-plugins, git-lfs, go-toolset:rhel8, golang, golang-github-openprinting-ipp-usb, grafana, grafana-pcp, gvisor-tap-vsock, podman, and skopeo), Slackware (libblockdev and xorg), SUSE (gdm, gstreamer-plugins-base, ignition, kernel, pam, redis, s390-tools, screen, systemd, and xorg-x11-server), and Ubuntu (godot, golang-1.22, libblockdev, node-express, pam, samba, and udisks2).

Inside this week's LWN.net Weekly Edition:

• Front: GNOME a11y; hierarchical scheduler; CoMaps; GPU restore; FAIR.pm; buffered I/O writeback; NFS; Lustre
• Briefs: Rocky Linux 10.0; Git 2.50; KDE Plasma 6.4; Kubernetes Slack; Radicle Desktop; Quote; ...
• Announcements: Newsletters, conferences, security updates, patches, and more.

The POSIX realtime model, which is implemented in the Linux kernel, can ensure that a realtime process obtains the CPU time it needs to get its job done. It can be less effective, though, when there are multiple realtime processes competing for the available CPU resources. The hierarchical constant bandwidth server patch series, posted by Yuri Andriaccio with work by Luca Abeni, Alessio Balsini, and Andrea Parri, is a modification to the Linux scheduler intended to make it possible to configure systems with multiple realtime tasks in a deterministic and correct manner.

The Lustre filesystem has a long history, some of which intersects with Linux. It was added to the staging tree in 2013, but was bounced out of staging in 2018, due to a lack of progress and a development model that was incompatible with the kernel's. Lustre may be working its way back into the kernel, though. In a filesystem-track session at the 2025 Linux Storage, Filesystem, Memory Management, and BPF Summit (LSFMM+BPF), Timothy Day and James Simmons led a discussion on how to get Lustre into the mainline.

The KDE Project has announced the Plasma 6.4 release. New features include more flexible tiling features, improvements to the Spectacle screen capture utility, a number of accessibility enhancements, and much more. See the changelog for a complete list of new features, enhancements, and bug fixes.

Security updates have been issued by Debian (gst-plugins-bad1.0, konsole, and libblockdev), Oracle (buildah, containernetworking-plugins, gimp, git-lfs, gvisor-tap-vsock, kernel, libvpx, podman, and skopeo), Red Hat (apache-commons-beanutils and thunderbird), Slackware (xorg), SUSE (gdm, golang-github-prometheus-alertmanager, golang-github-prometheus-node_exporter, golang-github-prometheus-prometheus, govulncheck-vulndb, grafana, kernel, Multi-Linux Manager, Multi-Linux Manager Client Tools, openssl-3, pam, python-cryptography, python-requests, python-setuptools, python3-requests, SUSE Manager Server, systemd, ucode-intel, xorg-x11-server, and xwayland), and Ubuntu (dwarfutils, mujs, node-katex, xorg-server, xorg-server-hwe-16.04, xorg-server-hwe-18.04, and xorg-server, xwayland).