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).
Version 2.4.0 of the LyXdocument processor has been released. LyX is a "What You See Is What YouMean" (WYSIWYM) application that offers GUI editing of LaTeXdocuments with import and export to PDF, HTML, OpenDocument, Word, andother formats. LyX 2.4.0 is the first major release in six years, andbrings support for EPUB, DocBook 5, improvedtable styles, and now uses Unicode (utf8) as its default encoding. Seethe full list of newfeatures on the LyX wiki, and releasenotes for information on known issues and caveats for thoseupgrading from earlier versions of LyX.
Debian had a major discussionabout mounting /tmp as a RAM-based tmpfs in 2012 but inertiawon out in the end. Debian systems have continued tostore temporary files on disk by default. Until now. A mere 12 years later, the project will be switching to a RAM-based /tmp in the Debian13 ("Trixie") release. Additionally, starting with Trixie, thedefault will be to periodically clean up temporary files automatically in/tmp and /var/tmp. Naturally, it involved a lengthy discussion first.
Security updates have been issued by AlmaLinux (python39:3.9 and python39-devel:3.9 and ruby:3.0), Debian (chromium, gst-plugins-base1.0, and kernel), Fedora (chromium, glances, glycin-loaders, gnome-tour, helix, helvum, kitty, libarchive, libipuz, librsvg2, loupe, maturin, ntpd-rs, plasma-workspace, and a huge list of Rust-based packages due to a "mini-mass-rebuild" that updated the toolchain to Rust 1.78 and picked up fixes for various pieces), Mageia (gifsicle, netatalk, openssl, python-jinja2, and unbound), Red Hat (kernel and kernel-rt), SUSE (bind, glibc, gstreamer-plugins-base, squid, and tiff), and Ubuntu (glibc).
The second 6.10 kernel prepatch is out fortesting. "Nothing feels particularly odd, but rc2 is usually fairly small andpeople are only starting to find regressions.So please go test some more."
The Fedora Project has announcedthe results of the Fedora Linux 40 election cycle. Four seats wereopen on the FedoraEngineering Steering Committee (FESCo), and the winners are StephenGallagher, Neal Gompa, Michel Lind, and Fabio Valentini. The FedoraCouncil had two seats open, and the winnersare Aleksandra Fedorova and Adam Samalik. One seat was open on theFedora MindshareCommittee, and the winneris Sumantro Mukherjee. Four seats were open for the first election to selectmembers of the EPELSteering Committee, which went to TroyDawson, Kevin Fenzi, Carl George, and Jonathan Wright.
The "pidfdfs" virtual filesystem was added to the 6.9 kernel release as away to export better information about running processes to user space. Itreplaced a previous implementation in a way that was, on its surface, fullycompatible 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 amisunderstanding with SELinux caused systems with pidfdfs to fail to bootproperly. That problem was quickly fixed, but it turns out that there wasone more surprise in store, showing just how hard ABI compatibility can beat times.
The 2024 Kernel Maintainers Summit will happen on September17 inVienna, Austria; it is an invitation-only event for a small group todiscuss important kernel-development problems. The call forproposals for this gathering has now been posted. One of the best waysto be invited to the event is to propose a topic that needs discussion inthat forum. The deadline for proposals is June18.
While BPF may be most famous for its use in the Linux kernel, there is actuallya growing effort to standardize BPF for use on other systems. These includeeBPF for Windows, but alsouBPF,rBPF,hBPF,bpftime, andothers. Some hardware manufacturers are evenconsidering integrating BPF directly into networking hardware. Dave Thalerled two sessions about all of the problems that cross-platform use inevitablybrings and the current status of the standardization work at the 2024Linux Storage,Filesystem, Memory Management, and BPF Summit.
A discussion of extensions to the statx()system call comes up frequently at the Linux Storage,Filesystem, Memory Management, and BPF Summit; this year's edition wasno exception. Kent Overstreet led the first filesystem-only session at thesummit on querying information about filesystems that have subvolumes andsnapshots. While it was billed as a discussion on statx()additions, it ranged more widely over new APIs needed for modern filesystems.
Greg Kroah-Hartman has announced the release of the 6.9.3 and 6.8.12 stable kernels. As usual, they containlots of important fixes throughout the tree. Note that 6.8.12 is the endof the line for the 6.8.x stable kernel series.
Security updates have been issued by Debian (python-pymysql), Fedora (chromium, mingw-python-requests, and thunderbird), Mageia (perl-Email-MIME and qtnetworkauth5 & qtnetworkauth6), Red Hat (gdisk and python39:3.9 and python39-devel:3.9 modules), SUSE (freerdp, gdk-pixbuf, gifsicle, glib2, java-1_8_0-ibm, kernel, libfastjson, libredwg, nodejs16, python, python3, python36, rpm, warewulf4, and xdg-desktop-portal), and Ubuntu (gst-plugins-base1.0, python-werkzeug, and tpm2-tss).
The Asahi Linux project worksto support Linux on Apple Silicon hardware. Theproject's flagshipdistribution is the FedoraAsahi Remix, which has its own installer (rather than Anaconda) toaccommodate the unique requirements of installing on Apple'shardware. Previously the installer was built by the Asahi project, but it has asked for (and received) an exceptionfrom the FedoraEngineering Steering Committee (FESCo) to include two binariesfrom upstream open-source projects so that the installer can be built on Fedorainfrastructure.
The FreeBSD Foundation has announcedthe 2024FreeBSD Community Survey Report. The report provides a summary of1,446 responses to an anonymous online survey of FreeBSD users. Itprovides insights into user profiles, typical usage, how the FreeBSDproject is viewed, as well as recommendations for expanding theFreeBSD community and contributor base:
When redesigning the LWN site in 2002, we thought long and hard aboutwhether the ability to post comments should be part of it; LWN had notoffered that feature for the first four years of its existence. There werealready plenty of examples of how comments can go bad by then, but wedecided to trust our readers to keep things under control. Much of thetime, that trust has proved justified, but there have been times wherethings have not gone so well. This time is quickly becoming one of thoseothers.
The GCC project has been working to support compiling to BPFfor some time. Jose Marchesi and David Faust spoke in an extended session at the 2024Linux Storage,Filesystem, Memory Management, and BPF Summitabout how that work has been going, and what is left for GCC to be on-par withLLVM with regard to BPF support. They also related tentative plans for howGCC BPF support would be maintained in the future.
The iomapblock-mapping abstraction is being used by more filesystems, in partbecause of its support for large folios. But there are some challenges inadopting iomap, which was the topic of a discussion led by Ritesh Harjaniin a combined storage and filesystem session at the 2024 Linux Storage,Filesystem, Memory Management, and BPF Summit. One of the main troublespots is how to handle metadata, which is not an area that iomap has been aimedat.
In the final session in the memory-management track of the 2024 Linux Storage,Filesystem, Memory-Management and BPF Summit, the exhausted group ofdevelopers looked one more time at the use of huge pages and the associatedproblem of memory fragmentation. At its worst, this problem can make hugepages harder (and more expensive) to allocate. Luis Chamberlain, who ranthe session, felt that people were worried about this problem, but thatthere 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 withmaintainer Andrew Morton to discuss the overall state of the community andthe development process. The 2024 gathering upheld that tradition towardthe end of the final day of the event. It seems that Morton and theassembled developers were all happy with how memory-management work isgoing, 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).
Alan Jowett gave a remote presentation at the 2024Linux Storage,Filesystem, Memory Management, and BPF Summit about what features could beadded to LLVM to make writing BPF programs easier. While there is nothing specificto LLVM about BPF code (and the next session in the track was led by GCCdeveloper Jose Marchesi about better support for that compiler), LLVM is currently the mostcommon way to turn C code into BPF bytecode. That translation, however, runsinto problems when the BPF verifier cannot understand the code LLVM'soptimizations produce.
One of the long-term goals of the folio conversion in the kernel'smemory-management subsystem is the replacement of the pagestructure, which describes a page of physical memory, with an eight-byte"memory descriptor". This change would reduce the overhead of trackingphysical memory, increase type safety, and make memory management moreflexible. Thus far, though, details on what the memory-descriptor futurewill look like have been relatively scarce. At the 2024 Linux Storage,Filesystem, Memory-Management and BPF Summit, Matthew Wilcox led adiscussion to try to fill in the picture somewhat.
Security updates have been issued by Debian (apache2, bluez, chromium, fossil, libreoffice, python-pymysql, redmine, and ruby-rack), Fedora (buildah, crosswords, dotnet7.0, glycin-loaders, gnome-tour, helix, helvum, libipuz, loupe, maturin, mingw-libxml2, ntpd-rs, perl-Email-MIME, and a huge list of Rust-based packages due to a "mini-mass-rebuild" that updated the toolchain to Rust 1.78 and picked up fixes for various pieces), Mageia (chromium-browser-stable, mariadb, and roundcubemail), Oracle (kernel, libreoffice, nodejs, and tomcat), and SUSE (cJSON, libfastjson, opera, postgresql15, python3, and qt6-networkauth).
Linus Torvalds released 6.10-rc1 and closedthe 6.10 merge window on May26. By that time, 11,534 non-mergechangesets had been pulled into the mainline for the next release; nearly5,000 of those came in after "The first half ofthe 6.10 merge window" was written. While the latter half of the mergewindow tends to focus more on fixes, there was also a lot of newfunctionality that landed during this time.
The maple tree data structure was addedduring the 6.1 development cycle; since then, it has taken itsplace at the core of the kernel's memory-management subsystem.Unsurprisingly, work on maple trees is not yet done. Maple-tree maintainerLiam Howlett ran a session in the memory-management track of the 2024 Linux Storage,Filesystem, Memory-Management and BPF Summit to discuss the currentstate of the maple tree and which features can be expected next.
Linus has released6.10-rc1 and closed the merge window for this release. For reasonsthat have not been spelled out, the codename for the release has beenchanged to "Baby Opossum Posse".
The 6.9.2, 6.8.11, 6.6.32, 6.1.92, 5.15.160, 5.10.218, 5.4.277, and 4.19.315stable kernel updates have all been released. Each contains animportant set of fixes. Users of those kernels should upgrade.
Using huge pages has been known for years to improve the performance ofmany workloads. But traditional huge pages, often sized by the CPU at 2MB,can be difficult to allocate and can waste memory due to internalfragmentation. Driven by both the folio transition and hardwareimprovements, attention to smaller, multi-size transparent huge pages(mTHPs) has been on the rise. In two memory-management-track sessions atthe 2024 Linux Storage,Filesystem, Memory-Management and BPF Summit, developers discussed thekernel's ability to reliably allocate mTHPs and the performance gains thatresult.
John Garry and Ted Ts'o led a discussion about supporting atomic writes for bufferedI/O, without any torn (or partial) writes to the device, at the 2024 Linux Storage,Filesystem, Memory Management, and BPF Summit. It is something of acontinuation of a discussion at last year'ssummit. The goal is to help PostgreSQL, which writes its data using16KB buffered I/O; it currently has to do a lot of extra work to ensurethat its data is safe on disk. A promise of non-torn, 16KB buffered writeswould allow the database to avoid doing double writes.
The original Linux kernel, posted in 1991, ran on a system with a 4KB pagesize. Over 30years later, most of us are still running on systemswith 4KB pages, even though the amount of installed memory has grown by afew orders of magnitude. It is generally accepted that using large pagesizes results in better performance for most applications, but allocatinglarger pages is often difficult. During a memory-management session at the 2024 Linux Storage,Filesystem, Memory-Management and BPF Summit, Yu Zhao presented hisideas on improving the allocation of huge pages in the kernel.
Kui-Feng Lee spoke early in the BPF track at the 2024Linux Storage,Filesystem, Memory Management, and BPF Summit about some of therecent improvements to BPF. These changes were largely driven by thesched_ext work that David Vernet had covered inthe previous talk. Lee focused on changes relevant to struct_opsprograms, but several of those changes apply to all BPF programs.
With the release of Fedora40 it's time tostart looking ahead to what Fedora41 has in store. One of the largestchanges planned for the next release is a switch toDNF5, a C++ rewrite of the DNFpackage manager. A previous attempt to make the switch, during the Fedora39 cycle, was called off, anddeferred to Fedora41. The developers have had nearly a year to addresscompatibility problems and bring DNF5 to a state suitable to replace DNF4. Signs point to a successful switch inthe upcoming release, though there may be a few surprises lurking for Fedora users.
The kernel contains a pair of related filesystems that, among other things,can be used for shared-memory applications; shmem is an internal mechanismused within the kernel, while the tmpfs filesystem is mounted andaccessible from user space. As is the case elsewhere in the kernel, thesesubsystems would benefit from the addition of large-folio support. Duringa joint storage, filesystem, and memory-management session at the 2024 Linux Storage,Filesystem, Memory-Management and BPF Summit, Daniel Gomez talked aboutthe work he is doing to add that support.
Security updates have been issued by Fedora (chromium, libreoffice, and thunderbird), Red Hat (.NET 7.0, .NET 8.0, gdk-pixbuf2, git-lfs, glibc, python3, and xorg-x11-server-Xwayland), SUSE (firefox, opensc, and ucode-intel), and Ubuntu (cjson and gnome-remote-desktop).
Swapping may be a memory-management technique at its core, but itsimplementation also involves the kernel's filesystem and storage layers.So it is not surprising that a session on the kernel's swap abstractionlayer, led by Chris Li at the 2024 Linux Storage,Filesystem, Memory-Management and BPF Summit, was held jointly by allthree of those tracks. Li has some ambitious ideas for an improvedsubsystem, but getting to a workable implementation may not be easy.
David Vernet's second talk at the 2024Linux Storage,Filesystem, Memory Management, and BPF Summit was a summary of the state ofsched_ext, the extensible BPF scheduler that LWNcovered in early May. In short, sched_ext is intended as a platform forrapid experimentation with schedulers, and a tool to let performance-mindedadministrators customize the scheduler to their workload. The patch set has seenseveral revisions, becoming more generic and powerful over time.Vernet spoke about what has been done in the past year,and what is still missing before sched_ext can be considered pretty muchcomplete.
The KDE Project has announced therelease of KDE Gear 24.05.0, with new features and updates for themore than 200 applications thatare part of the project. In addition to new versions of the Dolphinfile manager, Kdenlive videoeditor, and Elisa music player, thisrelease includes five applications new to KDE Gear: the Audex CD-ripper application,an application AccessibilityInspector, the FrancisPomodoro timer, Kalm to teach breathing techniques, and a Sokoban-like gamecalled Skladnik. See thefullchangelog for a complete list of changes.
Almost immediately after the merging of controlgroups, kernel developers set their sights on reimplementing themproperly. The second version of the control-group API started tricklinginto the kernel around the 3.16 release in 2014 and users have long sincebeen encouraged to migrate, but support for (and users of) the initial APIremain. At the 2024Linux Storage, Filesystem, Memory-Management and BPF Summit,memory-management developers discussed whether (and when) it might bepossible to remove the version-1 memory controller. The session was led byShakeel Butt and (participating remotely) Roman Gushchin.
In a combined storage and filesystem session at the 2024Linux Storage,Filesystem, Memory Management, and BPF Summit, Luis Chamberlain led adiscussion on filesystem support for block sizes larger than the usual 4KBpage size, which followed up on discussion from last year. While thesession was meant to look at the intersection of larger block sizeswith atomic block writes that avoid torn(partial) writes (which was also discussed last year), it mostly focused on thefilesystem side. Over time, theblock sizes offered by storage devices have risen from the original512bytes; Chamberlainwanted to discuss filesystem support for block sizes larger than 4KB.
The term "memory model" is used in a couple of ways within the kernel.Perhaps the more obscure meaning is the memory-management subsystem's viewof how physical memory is organized on a given system. A properrepresentation of physical memory will be more efficient in terms of memoryand CPU use. Since hardware comes in numerous variations, the kernelsupports a number of memory models to match; see this article for details. At the 2024 Linux Storage,Filesystem, Memory-Management and BPF Summit, Oscar Salvador,presenting remotely, made the case for removing one of those models.
ComputeExpress Link (CXL) is a data-center-oriented memory solution that,according to some in the industry, will yield large cost savings andperformance improvements. Others are more skeptical. At the 2024 Linux Storage,Filesystem, Memory-Management and BPF Summit, two sessions covered CXLand how it will be supported in future kernels.
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