Version 2.40.0 of the Git source-code management system is out. Changes include a new --merge-base option for merges, a built-in implementation of bisection, Emacs support for git jump, a fair number of smallish user-interface tweaks, and a lot of bug fixes. See the announcement and this GitHub blog entry for the details.

The kernel's software-interrupt ("softirq") mechanism was added prior to the 1.0 kernel release, but it implements a design seen in systems that were already old when Linux was born. For much of that time, softirqs have been an impediment to the kernel community's scalability and response-time goals, but they have proved resistant to removal. A recent discussion on a proposed new heuristic to mitigate a softirq-related performance problem may have reinvigorated interest in doing something about this subsystem as a whole rather than just tweaking the parameters of how it operates.

Greg Kroah-Hartman has announced the release of the 6.2.6, 6.1.19, 5.15.102, 5.10.174, 5.4.236, 4.19.277, and 4.14.309 stable kernels. These contain a small number of fixes, including a partial reversion that fixes WiFi problems that were introduced recently.

Security updates have been issued by Debian (imagemagick, libapache2-mod-auth-mellon, mpv, rails, and ruby-sidekiq), Fedora (chromium, dcmtk, and strongswan), Mageia (chromium-browser-stable, dcmtk, kernel, kernel-linus, libreswan, microcode, redis, and tmux), SUSE (postgresql14 and python39), and Ubuntu (linux-kvm, linux-raspi-5.4, and thunderbird).

The 6.3-rc2 kernel prepatch is out.

This one looks fairly normal, although if you look at the diffs, they are dominated by the removal of a staging driver (r8188eu) that has been superceded by a proper driver. That removal itself is 90% of the diffs. But if you filter that out, it all looks normal

The 6.2.4 and 6.1.17 stable kernels have been released; each contains a pair of reverts for problematic patches in yesterday's updates. But it doesn't stop there; also released are 6.2.5, 6.1.18, and 5.15.100 with another set of important fixes.

Update: they keep on coming: the large 5.10.173, 5.4.235, 4.19.276, and 4.14.308 kernels have been released, as has the single-revert 5.15.101 update

The sustainability of free software continues to be mostly uncharted waters. No team is the same as any other, so copying, say, the Blender Foundation’s approach to governance will, most likely, not work for other projects. But there is value in understanding how various non-commercial organizations operate in order to make informed decisions for the governance of new ones. In late 2021, the FreeCAD team launched the FreeCAD Project Association (FPA) to handle the various assets that belong to this free 3D CAD project. In this interview, Yorik van Havre, a longtime FreeCAD developer — and current president of the Association — guides us through the process of starting and managing the FPA.

The 6.2.3, 6.1.16, and 5.15.99 stable kernel updates have been released. The first updates after the close of a merge window tend to be huge, and these ones certainly fit that description.

Security updates have been issued by Debian (chromium and wireless-regdb), Fedora (caddy, python-cryptography, and redis), Oracle (gnutls), SUSE (hdf5, opera, python-Django, redis, tomcat, and xen), and Ubuntu (apache2 and snakeyaml).

The kernel's completely fair scheduler (CFS) has the job of managing the allocation of CPU time for most of the processes running on most Linux systems. CFS was merged for the 2.6.23 release in 2007 and has, with numerous ongoing tweaks, handled the job reasonably well ever since. CFS is not perfect, though, and there are some situations it does not handle as well as it should. The EEVDF scheduler, posted by Peter Zijlstra, offers the possibility of improving on CFS while reducing its dependence on often-fragile heuristics.

Version 1.68.0 of the Rust language has been released. Changes include the stabilization of the "sparse" Cargo protocol, the ability for (some) applications to recover from memory-allocation failures, and "local Pin construction":

The new pin! macro constructs a Pin<&mut T> from a T expression, anonymously captured in local state. This is often called stack-pinning, but that "stack" could also be the captured state of an async fn or block.

Security updates have been issued by CentOS (kernel, pesign, samba, and zlib), Oracle (kernel), Slackware (httpd), SUSE (emacs, libxslt, nodejs12, nodejs14, nodejs16, openssl, poppler, python-py, python-wheel, xen, and xorg-x11-server), and Ubuntu (linux-gcp-5.4, linux-gkeop, opusfile, and samba).

The LWN.net Weekly Edition for March 9, 2023 is available.

Way back in 2009, we looked at the presto plugin for yum, which added support for DeltaRPMs to Fedora. That package format allows just the binary differences (i.e. the delta) between an installed RPM and its update to be transmitted, which saves network bandwidth; the receiving system then creates the new RPM from those two pieces before installing it. Support for DeltaRPMs was eventually added to the distribution by default, though the feature has never really lived up to expectations—and hopes. Now, it would seem that Fedora is ready to, in the words of project leader Matthew Miller, "give DeltaRPMs a sad, fond farewell".

Version 4.18 of the Samba interoperability suite is out. Changes include some significant performance improvements, better error messages, and more; click below for the details.

Version 4.15 of the "anything to PostScript" filter a2ps has been released — the first release since 2007. "This release contains few user-visible changes. It does however contain a lot of changes “under the hood”: code clean-up, etc. Therefore, it’s likely that there are new bugs."

Security updates have been issued by Debian (apr), Fedora (c-ares), Oracle (curl, kernel, pesign, samba, and zlib), Red Hat (curl, gnutls, kernel, kernel-rt, and pesign), Scientific Linux (kernel, pesign, samba, and zlib), SUSE (libX11, python-rsa, python3, python36, qemu, rubygem-rack, xorg-x11-server, and xwayland), and Ubuntu (libtpms, linux-ibm, linux-raspi, linux-raspi, python3.7, python3.8, and sofia-sip).

Many wireless sensors broadcast their data using Bluetooth Low Energy (BLE). Their data is easy to receive, but decoding it can be a challenge. Each manufacturer uses its own format, often tied to its own mobile apps. Integrating all of these sensors into a home-automation system requires a lot of custom decoders, which are generally developed by reverse-engineering the protocols. The goal of the BTHome project is to change this: it offers a standardized format for sensors to broadcast their measurements using BLE. BTHome is supported by the Home Assistant home-automation software and by a few open-firmware and open-hardware projects.

Asahi Lina has posted an initial version of a Rust-based driver for Apple AGX graphics processors; the posting includes a fair amount of Rust infrastructure for graphics drivers in general.

While developing the driver, I tried to make use of Rust's safety and lifetime features to provide not just CPU-side safety, but also partial firmware-ABI safety. Thanks to this, it has turned out to be a very stable driver even though GPU firmware crashes are fatal (no restart capability, need to reboot!) and the FW/driver interface is a huge mess of unsafe shared memory structures with complex pointer chains.

The Flathub organization (in the form of Robert McQueen) has posted a lengthy update on the state of Flathub and its plans for the coming year.

So far, the GNOME Foundation has acted as an incubator and legal host for Flathub even though it’s not purely a GNOME product or initiative. Distributing software to end users along with processing and forwarding payments and donations also has a different legal profile in terms of risk exposure and nonprofit compliance than the current activities of the GNOME Foundation. Consequently, we plan to establish an independent legal entity to own and operate Flathub which reduces risk for the GNOME Foundation, better reflects the independent and cross-desktop interests of Flathub, and provides flexibility in the future should we need to change the structure.