GNU/Linux Coverage in LWN (Mostly Kernel)

posted by Roy Schestowitz on Jun 25, 2026

• Kernel Space

  • LWN ☛ Automatic mTHP creation in 7.2

    The Linux kernel has long tried to use huge pages as a way to improve performance, sometimes with more success than others. The size of huge pages has traditionally been imposed by the hardware, which typically only offers a couple of relatively large options. In more recent times, though, the use of multi-size transparent huge pages (mTHPs), with more flexible sizing implemented in software, has been growing. If all goes well, the 7.2 development cycle will include the addition of a new feature, contributed by Nico Pache, to make the use of mTHPs even more transparent.

  • LWN ☛ An overlayfs update

    In a shortened session in the filesystem track at the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit, Amir Goldstein gave an update on the overlayfs union filesystem. There are some new features over the last few years that he wanted to mention, along with looking at the status of nesting overlayfs layers. The composefs use case that was discussed at the summit in 2023 has led to some interesting changes to overlayfs.

    Overlayfs provides a way to create a single mounted filesystem that is created from multiple other filesystems fused together. It presents a union of the files in the various filesystems, though the underlying filesystems are ordered so that entries from filesystems above take precedence over the same file and directory names in the lower layers. Often, the top layer is writable so that users can change the files as they appear in the mounted overlayfs without actually changing anything in the (typically read-only) lower layers.

  • LWN ☛ Some buffer-heads cleanup work

    Jan Kara has been working on cleaning up how buffer heads are used by some kernel filesystems. In a short filesystem-track session at the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit, he gave an update on that work and where it is headed. Topics included generic infrastructure to track buffer heads for metadata, a buffer-head cleanup for the Amiga filesystem, and some planned locking fixes.

    Buffer heads are ""ancient stuff"", he began, having been part of the kernel ""basically since day zero of Linux"". They are used to track filesystem information at the granularity of blocks, rather than folios. Kernel filesystem developers are trying to remove buffer heads from the data path in filesystems, but they are still used in the metadata path for many filesystems. Overall, buffer heads are not going away anytime soon because those filesystems need fine-grained tracking for the state of individual blocks.

  • LWN ☛ Development statistics for the 7.1 kernel

    Linus Torvalds released the 7.1 kernel as expected on June 14. This development cycle brought in a lot of new features — and a lot of new developers as well. The time has come for our traditional look at where the changes in 7.1 came from, with a digression into how our community may be changing in general.

    This release saw the merging of 15,849 non-merge changesets from 2,479 developers. That makes 7.1 one of the busiest development cycles in the kernel's history; only four other releases brought in more commits. The 6.7 release remains the busiest ever, with 17,284 commits; the size of that release was driven by the ill-fated addition of the bcachefs filesystem and all of its development history. The 5.8, 5.10, and 5.13 also brought in more commits than 7.1, though by much smaller margins.

• Distributions and Operating Systems

  • Fedora / IBM

    • LWN ☛ The state of Fedora in 2026 [Ed: Conflict of interest as the author worked there]

      On June 15 at Fedora's Flock conference, held in Prague, Fedora Project Leader (FPL) Jef Spaleta delivered a short "State of Fedora" keynote that provided a bit of insight into the status of the project. Topics included the overall growth for Fedora usage, ways to increase contributions, and an alarming decline in the number of active packagers working on the project.

      I did not attend Flock this year but I did watch the live stream; the unedited video is available now, and edited videos should be published soon. Spaleta's slides are not yet available, but are expected to be posted to the session page at any time.