P4, short for "Programming Protocol-independent Packet Processors", is a programming language aimed at networking devices; it is useful for the configuration of firewalls and complicated routing architectures. Since a lot of advanced networking is done with Linux systems, it stands to reason that there would be value in supporting P4 and, indeed, an implementation of P4 in the kernel's traffic-control subsystem was first posted by Jamal Hadi Salim at the beginning of 2023. After nearly 18 months, though, this feature has not been merged, and the chances of that happening would appear to be getting worse.

Version 5.40.0 of the Perl language has been released. "Perl 5.40.0 represents approximately 11 months of development since Perl 5.38.0 and contains approximately 160,000 lines of changes across 1,500 files from 75 authors". Significant changes include a new __CLASS__ keyword, a :reader: attribute for field variables, a new "^^" logical-XOR operator (because two of those were not enough), moving "try/catch" out of the experimental category, and more; see this page for lots of details.

The 6.10-rc3 kernel prepatch is out. "So things look good, the water is warm, please jump right in and keep testing,"

The kernel's user-space ABI does not lack for ring buffers; they have been defined for subsystems like BPF, io_uring, perf, and tracing, for example. Naturally, each of those ring buffers is unique, with no common interface between them. The natural response to this ABI proliferation is, of course, to add yet another ring buffer as the generic option; that is the intent of this patch series from Kent Overstreet adding a new set of system calls for ring buffers.

The LWN.net Weekly Edition for June 6, 2024 is available.

We have just received the sad news that longtime core BSD developer Mike Karels has died; he will certainly be missed.

Version 6.2 of the Incus container-management system is out. "This release contains the second wave of changes contributed by students of the University of Texas at Austin and a few other features and improvements." The features include a new incus top command, a new API for system load information, and more.

In the recent discussion on commenting at LWN, several readers asked for the ability to hide subthreads of a long comment stream. That feature has just been added; it is also integrated with the three comment-display modes and with comment filtering, removing the need for JavaScript for filtering. Hiding is not persistent; no extra data is stored at either end.

Give it a try; if you have comments on the new mechanism, this is the place to put them.

Security updates have been issued by Mageia (chromium-browser-stable, git, libreoffice, microcode, python-requests, webkit2, and wireshark), Oracle (container-tools:ol8, glibc, go-toolset:ol8, idm:DL1 and idm:client, less, python39:3.9 and python39-devel:3.9, ruby:3.0, and virt:ol and virt-devel:rhel), Red Hat (nodejs, nodejs:18, python-idna, and ruby:3.1), and SUSE (389-ds, ffmpeg, ffmpeg-4, gnutls, gstreamer-plugins-base, libhtp, mariadb104, poppler, python-python-jose, squid, and unbound).

The second 6.10 kernel prepatch is out for testing. "Nothing feels particularly odd, but rc2 is usually fairly small and people are only starting to find regressions. So please go test some more."

The "pidfdfs" virtual filesystem was added to the 6.9 kernel release as a way to export better information about running processes to user space. It replaced a previous implementation in a way that was, on its surface, fully compatible while adding a number of new capabilities. This transition, which was intended to be entirely invisible to existing applications, already ran into trouble in March, when a misunderstanding with SELinux caused systems with pidfdfs to fail to boot properly. That problem was quickly fixed, but it turns out that there was one more surprise in store, showing just how hard ABI compatibility can be at times.

The 2024 Kernel Maintainers Summit will happen on September 17 in Vienna, Austria; it is an invitation-only event for a small group to discuss important kernel-development problems. The call for proposals for this gathering has now been posted. One of the best ways to be invited to the event is to propose a topic that needs discussion in that forum. The deadline for proposals is June 18.

The developers of the Krita painting application are celebrating 25 years of development with a detailed history of the project.

A quarter century. That's how long we've been working on Krita. Well, what would become Krita. It started out as KImageShop, but that name was nuked by a now long-dead German lawyer. Then it was renamed to Krayon, and that name was also nuked. Then it was renamed to Krita, and that name stuck.

The LWN.net Weekly Edition for May 30, 2024 is available.

When redesigning the LWN site in 2002, we thought long and hard about whether the ability to post comments should be part of it; LWN had not offered that feature for the first four years of its existence. There were already plenty of examples of how comments can go bad by then, but we decided to trust our readers to keep things under control. Much of the time, that trust has proved justified, but there have been times where things have not gone so well. This time is quickly becoming one of those others.

In the final session in the memory-management track of the 2024 Linux Storage, Filesystem, Memory-Management and BPF Summit, the exhausted group of developers looked one more time at the use of huge pages and the associated problem of memory fragmentation. At its worst, this problem can make huge pages harder (and more expensive) to allocate. Luis Chamberlain, who ran the session, felt that people were worried about this problem, but that there was little data on how severe it truly is.

A longstanding tradition in the memory-management track of the Linux Storage, Filesystem, Memory-Management and BPF Summit is a session with maintainer Andrew Morton to discuss the overall state of the community and the development process. The 2024 gathering upheld that tradition toward the end of the final day of the event. It seems that Morton and the assembled developers were all happy with how memory-management work is going, but there is always room for improvement.

Security updates have been issued by Debian (less), Mageia (chromium-browser-stable), SUSE (apache2, java-1_8_0-openj9, kernel, libqt5-qtnetworkauth, and openssl-3), and Ubuntu (netatalk and python-cryptography).

Geoff Huston suggests that it is time to give up on DNSSEC and look for a better way to secure the Internet namespace.

What appears to be very clear (to me at any rate!) is that DNSSEC as we know it today is just not going anywhere. It's too complex, too fragile and just too slow to use for the majority of services and their users. Some value its benefits highly enough that they are prepared to live with its shortcomings, but that's not the case for the overall majority of name holders and for the majority of users, and no amount of passionate exhortations about DNSSEC will change this.