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Roman Gushchin began his session in the memory-management track of the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit by saying that the community has seen a lot of proposals adding BPF-based interfaces for memory management. None of them have made their way into the mainline, though. He wanted to explore the ways in which BPF might be helpful and the obstacles that have kept BPF-based solutions out so far. This session was followed by a discussion led by Shakeel Butt on what the requirements for a new, BPF-based interface for memory control groups might look like.

Greg Kroah-Hartman has announced the 7.0.8, 6.18.31, 6.12.89, 6.6.139, 6.1.173, 5.15.207, and 5.10.256 stable kernels. These kernels contain a patch for CVE-2026-46333 a vulnerability reported by the Qualys Security Advisory team, though Jann Horn proposed a patch in 2020. The vulnerability has a proof-of-concept exploit published already. Some of the kernels have additional patches for other bugs; as always, users are advised to upgrade.

Recent times have seen a lot of effort put into the implementation of the kexec handover and live update orchestrator features in the Linux kernel. But that work is not yet complete. At the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit, Pratyush Yadav led a memory-management-track session on adding the ability to preserve hugetlbfs-provided memory during the live-update process.

Security updates have been issued by Debian (ffmpeg, gsasl, nodejs, postgresql-15, postgresql-17, python3.9, and thunderbird), Fedora (expat, firefox, freerdp, GitPython, kernel, php, rust-podman-sequoia, rust-rpm-sequoia, rust-sequoia-chameleon-gnupg, rust-sequoia-git, rust-sequoia-keystore-server, rust-sequoia-octopus-librnp, rust-sequoia-openpgp, rust-sequoia-sop, rust-sequoia-sq, and rust-sequoia-sqv), Mageia (awstats, libreoffice, perl-HTTP-Tiny, and tomcat), Oracle (corosync, freerdp, gimp, git-lfs, glib2, jq, kernel, krb5, libsoup3, libtiff, openexr, thunderbird, uek-kernel, and yggdrasil), Red Hat (podman and skopeo), SUSE (amazon-ssm-agent, avahi, c-ares, cairo, containerd, cpp-httplib, dnsmasq, dovecot24, ffmpeg-4, firefox, helm, ImageMagick, iproute2, kernel, krb5, libtpms, ongres-scram, ongres-stringprep, plexus-testing, maven, maven-doxia, mojo-parent, sisu, openCryptoki, openssh, perl-Text-CSV_XS, php8, python-lxml, python-Twisted-doc, python311-click, python311-GitPython, rclone, regclient, and syncthing), and Ubuntu (avahi).

The kernel's control-group subsystem works well for resource management, Chris Li said at the beginning of his memory-management-track session at the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit. Control groups work less well for other use cases, though. He was there to present his proposed enhancement, called "policy groups", that would address some of the shortcomings that he has encountered. A consensus on how this feature should look still seems distant, though.

In back-to-back sessions at the start of the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit (which spilled over into a third slot), the atomic-buffered-writes feature was discussed. In the first session, Pankaj Raghav and Andres Freund set the stage with an introduction to the problem, along with a use case for its solution: the PostgreSQL database system. In the second, Ojaswin Mujoo described a potential way forward for the feature using an approach based on writethrough, which effectively means that the kernel immediately writes the data to disk instead of waiting for writeback from the page cache to occur. As might be expected, there was quite a bit of discussion among the assembled filesystems and storage developers during the combined sessions for those tracks.

Greg Kroah-Hartman has announced the release of the 7.0.7, 6.18.30, and 6.12.88 stable kernels. These kernels do not include a patch for the Fragnesia local-privilege-escalation exploit that came to light on May 13, but do include many other important fixes throughout the tree. Users are, as always, advised to upgrade.

The kernel's reverse-mapping machinery is charged with locating the page-table entries that refer to a given page in memory. The reverse mapping of anonymous pages is handled differently than for file-backed pages. The kernel's implementation of reverse mapping for anonymous pages is, according to Lorenzo Stoakes in his proposal for a memory-management-track session at the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit, "a very broken abstraction", due to its complexity. It also has some performance problems. Stoakes was there to present, in raw form, a proposed replacement that he calls a "COW context".

Security updates have been issued by AlmaLinux (gimp, jq, and yggdrasil), Debian (nghttp2 and thunderbird), Fedora (chromium, firefox, freerdp, GitPython, kernel, kernel-headers, krb5, nano, nix, nodejs20, php, python-click, python-django5, SDL2_image, and xen), Mageia (dnsmasq, flatpak, kernel, kmod-virtualbox, kernel-linus, perl-Net-CIDR-Lite, perl-XML-LibXML, and redis), SUSE (dnsmasq, firefox, jupyter-jupyterlab, kernel, krb5, libvinylapi3, log4j, Mesa, mozjs60, NetworkManager, OpenImageIO, python-Mako, python-Pillow, and python39), and Ubuntu (dnsmasq and nginx).

Inside this week's LWN.net Weekly Edition:

• Front: Fedora AI; Forgejo "carrot" disclosure; memory-management maintainership; huge THPs; mshare; 64KB base pages; DAMON; direct map.
• Briefs: Dirty Frag; Fragnesia; Mythos and curl; killswitch; Debian reproducible builds; KDE investment; Quotes ...
• Announcements: Newsletters, conferences, security updates, patches, and more.

A push by Red Hat employees to create a Fedora "AI Developer Desktop" with support for out-of-tree kernel drivers and AI toolkits has been met with objections from some long-time members of the Fedora community. After more than a month of sometimes heated discussion, the Fedora Council had voted to approve the initiative; however, a last-minute change to vote against the proposal by council member Justin Wheeler has (at least temporarily) sent it back to the drawing board.

Sam James has sent an announcement to the OSS Security mailing list about another local-privilege-escalation (LPE) exploit in the same class as Dirty Frag, called "Fragnesia". From the disclosure:

This is a separate bug in the ESP/XFRM from dirtyfrag which has received its own patch. However, it is in the same surface and the mitigation is the same as for dirtyfrag.

It abuses a logic bug in the Linux XFRM ESP-in-TCP subsystem to achieve arbitrary byte writes into the kernel page cache of read-only files, without requiring any race condition.

James noted that there is a patch in the works, but it has not yet been pulled into Linus Torvalds's tree nor into any of the stable kernels. A proof of concept exploit is also available.

When Brendan Jackman proposed a session for the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit, his topic was "a pagetable library for the kernel". During the actual memory-management-track session, though, he stated that the idea had "fizzled" and he was going to cover related topics instead. What resulted was a session on ways to efficiently manage pages that are not present in the kernel's direct map.

Linux can share memory between processes, but each process (almost always) has its own set of page tables. In situations where vast numbers of processes are sharing a memory region, the combined size of the page tables can exceed that of the shared memory itself. There has, thus, long been an interest in enabling unrelated processes to share page tables referring to shared memory. Anthony Yznaga is the latest developer to try to push this idea (known as "mshare") forward; he described the status of that work in a memory-management-track discussion at the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit (LSFMM+BPF).

Security updates have been issued by AlmaLinux (corosync, freerdp, git-lfs, glib2, jq, kernel-rt, krb5, libpng, libtiff, openexr, and thunderbird), Debian (exim4), Mageia (apache, perl-Gazelle, php, and sed), Slackware (expat), SUSE (assimp-devel, go1.26, libQt6Svg6, python-jupyterlab, raylib, thunderbird, tor, and trivy), and Ubuntu (exim4).