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There are a lot of things people expect the Linux kernel to do correctly. Some of these are checked by testing or static analysis; a few are ensured by run-time verification: checking a live property of a running Linux system. For example, the scheduler has a handful of different correctness properties that can be checked in this way. Nam Cao posted a patch series that aims to extend the kinds of properties that the kernel's run-time verification system can check, by adding support for linear temporal logic (LTL). The patch set has seen eleven revisions since the first version in March 2025, and recently made it into the linux-next tree, from where it seems likely to reach the mainline kernel soon.

In the first keynote at EuroPython 2025 in Prague, Savannah Bailey described her path to becoming a CPython core developer in November 2024. She started down that path a few years earlier and her talk was meant to inspire others—not to slavishly follow hers, but to create their own. In the talk, entitled "You don't have to be a compiler engineer to work on Python", she had lots of ideas for those who might be thinking about contributing and are wondering how to do so.

Security updates have been issued by AlmaLinux (firefox, icu, kernel-rt, libtpms, redis:6, redis:7, and sqlite), Fedora (chromium and cloud-init), Oracle (icu, java-1.8.0-openjdk, java-21-openjdk, kernel, nodejs:22, perl, and sqlite), SUSE (docker, java-1_8_0-openj9, libxml2, python-starlette, and thunderbird), and Ubuntu (cloud-init, linux-azure, linux-azure-5.4, linux-azure-fips, linux-raspi, linux-raspi-5.4, and perl).

The HeliumOS project has announced the release of HeliumOS 10. It is relatively new image-based ("atomic") desktop distribution based on packages from CentOS Stream and AlmaLinux, with a goal of providing 10 years of support. HeliumOS 10 uses the KDE Plasma Desktop, Zsh as its default shell, and Btrfs as its default filesystem.

Priority inversion comes about when a low-priority task holds a resource that is also needed by a high-priority task, preventing the latter from running. This problem is made much worse if the low-priority task is unable to gain access to the CPU and, as a result, cannot complete its work and free the resources it holds. Proxy execution is a potential solution to this problem, but it is a complex solution that has been under development for several years; LWN first looked at it in 2020. The 6.17 kernel is likely to contain an important step forward for this long-running project.

Version 2.42 of the GNU C Library has been released. Changes include the addition of a number of new math functions, support for arbitrary baud rates in the termios.h interface, support for SFrame-based stack tracing (described in this article), support for memory guard pages, and a handful of security fixes.

Security updates have been issued by AlmaLinux (freerdp, git-lfs, golang-github-openprinting-ipp-usb, grafana, grafana-pcp, icu, ipa, iputils, krb5, libvpx, nodejs:22, osbuild-composer, perl, python-tornado, qt6-qtbase, sqlite, unbound, valkey, wireshark, and yggdrasil), Debian (libfastjson and php8.2), Fedora (glibc), Oracle (firefox, icu, perl, and unbound), Red Hat (389-ds-base, glib2, icu, libtpms, redis:6, redis:7, and yelp), SUSE (boost, forgejo-longterm, java-11-openj9, java-17-openj9, java-1_8_0-openj9, kernel, nginx, and salt), and Ubuntu (linux-xilinx-zynqmp, openjdk-8, openjdk-lts, poppler, and sqlite3).

Till Kamppeter, co-founder and lead of the OpenPrinting project, has put out a call for sponsors after being laid off by Canonical:

I want to continue doing OpenPrinting for a living, and need a way to do so. I am currently working with the Linux Foundation to make OpenPrinting an [organization] which can receive sponsor funding. So now I am looking for sponsors.

Even greater would be, if independent of this somebody could hire me to continue OpenPrinting...

The 6.16 development cycle was another busy one, with 14,639 non-merge changesets pulled into the mainline — just 18 commits short of the total for 6.15. The 6.16 release happened on July 27, as expected. Also as expected, LWN has put together its traditional look at where the code for this release came from.

Fedora's quality team is looking to reduce the scope of test coverage and change the project's release criteria to drop some features from the list of release blockers. This is, in part, an exercise in getting rid of criteria, such as booting from optical media, that are less relevant. It is also a necessity, since the Red Hat team focusing on Fedora quality assurance (QA) is only half the size it was a year ago.

Security updates have been issued by Debian (audiofile, libcaca, libetpan, libxml2, php7.4, snapcast, and thunderbird), Fedora (glibc, iputils, mingw-binutils, and thunderbird), Red Hat (kernel, kernel-rt, mod_auth_openidc, and mod_auth_openidc:2.3), SUSE (afterburn, apache2, atop, chromedriver, chromium, cloud-init, deepin-feature-enable, firefox, firefox-esr, grafana, grype-db, gstreamer-plugins-bad, javamail, jupyter-jupyterlab-templates, jupyter-nbdime, konsole, libetebase, libxmp, minio-client-20250721T052808Z, MozillaFirefox, MozillaFirefox-branding-SLE, opera, pdns-recursor, perl-Authen-SASL, polkit, python-Django, python3-pycares, python311-starlette, rpi-imager, ruby3.4-rubygem-thor, spdlog, thunderbird, varnish, viewvc, and xtrabackup), and Ubuntu (openjdk-21-crac).

The good folks at Linode still have not managed to fix whatever broke in their data center, so we are running on an emergency backup server. Things seem to be working, but the occasional glitch is to be expected. Please accept our apologies for the extended downtime!

Linus has released the 6.16 kernel:

It's Sunday afternoon, and the release cycle has come to an end. Last week was nice and calm, and there were no big show-stopper surprises to keep us from the regular schedule, so I've tagged and pushed out 6.16 as planned.

Headline changes in this release include enabling five-level page tables by default on x86 systems, a number of core-dump changes including the ability to send core dumps to a socket, the ability to create pipes in io_uring, atomic-write support in the XFS filesystem, the elimination of block-layer bounce buffering, a new DMA-mapping API, an option to block file descriptors passed in via Unix-domain sockets, and more.

See the LWN merge-window summaries (part 1, part 2) and the KernelNewbies 6.16 page for more information.

There is an inherent limit to the privacy of the public cloud. While Linux can isolate virtual machines (VMs) from each other, nothing in the system's memory is ultimately out of reach for the host cloud provider. To accommodate the most privacy-conscious clients, confidential computing protects the memory of guests, even from hypervisors. But the Linux cloud stack needs to be rethought in order to host confidential VMs, juggling two goals that are often at odds: performance and security.

Security updates have been issued by AlmaLinux (git, kernel, nginx:1.24, and sudo), Fedora (dpkg, java-21-openjdk, java-25-openjdk, java-latest-openjdk, and valkey), Oracle (apache-commons-vfs, sudo, tigervnc, and xorg-x11-server), Red Hat (kernel, krb5, and openssh), SUSE (gnutls, ImageMagick, iputils, kernel-livepatch-MICRO-6-0-RT_Update_10, kubernetes1.18, libarchive, ovmf, python, and salt), and Ubuntu (iputils, linux-aws-6.14, linux-raspi, openjdk-21, and openjdk-24).

Version 0.1 of the Wayback project has been released:

Wayback is an X11 compatibility layer that allows for running full X11-only desktop environments using Wayland. It is essentially an X11 server backed by Wayland, leveraging wlroots and Xwayland. Our goal is for Wayback to eventually be a completely drop-in replacement to the Xorg binary, thus reducing maintenance burden for distro maintainers.

Ever since Wayback was announced on June 28, we have been making lots of progress to get it as stable and functional as possible, and while this is a preview release it is already daily-driveable by users with simple requirements, as long as they don't mind bugs.

The release is considered alpha-quality and is missing a number of features, including multi-monitor support and DPMS, but adventurous users can find the code here.

The 6.15.8, 6.12.40, 6.6.100, and 6.1.147 stable kernels have been released. Each contains important fixes throughout the kernel tree, as usual.

People tend to put a lot of trust into their phones. Those devices have access to no end of sensitive data about our lives — our movements, finances, communications, and more — so phones belonging to even relatively low-profile people can be high-value targets. Android devices run free software, at least at some levels, so it should be possible to ensure that they are working in their owners' interests. Off-the-shelf Android installations tend to fall short of that goal. The GrapheneOS Android rebuild is an attempt to improve on that situation.

Security updates have been issued by Debian (chromium, firefox-esr, and mediawiki), Fedora (firefox), Oracle (git, kernel, redis, and sudo), Red Hat (aardvark-dns, firefox, kernel, and thunderbird), Slackware (httpd), SUSE (php7, php8, and salt), and Ubuntu (linux-raspi-realtime and ruby-rack).

Inside this week's LWN.net Weekly Edition:

• Front: Debian's security processes; Tor; Immutability for Python; CPU scheduler; QUIC; Rust abstractions.
• Briefs: Brief news items from throughout the community.
• Announcements: Newsletters, conferences, security updates, patches, and more.