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Version1.71.0 of the Rust language has been released. Changes this timeinclude the C-unwindABI, an upgrade to musl 1.2, and more.

The kernel-development process routinely absorbs large changes tofundamental subsystems and still produces stable releases every nine or tenweeks. On occasion, though, the development community's luck runs out.The per-VMA locking work that went into the6.4 release is a case in point; it looked like a well-tested change thatimproved page-fault scalability. There turned out to be a few demonshiding in that code, though, that made life difficult for early adopters ofthe 6.4 kernel.

Security updates have been issued by Debian (ruby-doorkeeper), Fedora (mingw-nsis and thunderbird), Red Hat (bind9.16, nodejs, nodejs:16, nodejs:18, python38:3.8 and python38-devel:3.8, and rh-nodejs14-nodejs), Slackware (krb5), SUSE (geoipupdate, installation-images, libqt5-qtbase, python-Django1, and skopeo), and Ubuntu (knot-resolver, lib3mf, linux, linux-aws, linux-kvm, linux-lowlatency, linux-raspi, linux, linux-aws, linux-kvm, linux-lts-xenial, linux-azure, linux-gcp, linux-ibm, linux-oracle, linux-azure-fde, linux-xilinx-zynqmp, and scipy).

The LWN.net Weekly Edition for July 13, 2023 is available.

The kdevopskernel-testing framework has come up at several earlier summits, including in two separate sessions at last year's event.Testing kernel filesystems and the block layer, not to mention lots ofother kernel subsystems, has become increasinglyimportant over time. So it was nosurprise that Luis Chamberlain led a combined storage and filesystem session at the2023 Linux Storage, Filesystem,Memory-Management and BPF Summit to talk more about testing, theresources needed for it, and what can be done to improve it. It was thefinal session for this year's summit, so this article completes our coverage.

Over on the Open Source Initiative (OSI) blog, the organization has announced the Open Policy Alliance (OPA), which is meant to bring together various non-profit organizations to help educate and inform US policy makers about open-source software and its needs:

Security updates have been issued by Debian (erlang, symfony, thunderbird, and yajl), Fedora (cutter-re, kernel, rizin, and yt-dlp), Red Hat (grafana), SUSE (kernel and python-Django), and Ubuntu (dotnet6, dotnet7 and firefox).

The Filesystemin Userspace (FUSE) framework can be used to create a "stacked"filesystem, where the FUSE piece adds specialized functionality(e.g. reporting different file metadata) atop anunderlying kernel filesystem. The performance of such filesystems leaves alot to be desired, however, sothe FUSEBPF filesystem has been proposed to try to improve the performance tobe close to that of the underlying native filesystem. It came up in thecontext of a session on FUSE passthroughearlier in the2023 Linux Storage, Filesystem,Memory-Management and BPF Summit, but the details of FUSE BPF were morefully described by Daniel Rosenberg in a combined filesystem and BPFsession on the final day of the summit.

The 6.4.3 stable kernel has been released;it contains a handful of fixes, mostly for problems associated with the per-VMA locking code. Anybody running 6.4probably wants this update.Note that there is a much larger 6.3.13update going through a longer-than-usual review process that should show upsoon.Update: 6.3.13 is now out. Notethat this is the last 6.3.x update.

SUSE has announcedthat it is getting into the business of creating RHEL clones and investing$10million in the project.

Security updates have been issued by Debian (mediawiki and node-tough-cookie), Red Hat (bind, kernel, kpatch-patch, and python38:3.8, python38-devel:3.8), SUSE (kernel, nextcloud-desktop, and python-tornado), and Ubuntu (dwarves-dfsg and thunderbird).

Linus Torvalds released6.5-rc1 and closed the merge window for this development cycle onJuly9. By that point, 11,730 non-merge changesets had been pulledinto the mainline for 6.5; over 7,700 of those were pulled afterthe first-half merge-window summary waswritten. The second half of the merge window saw a lot of code coming intothe mainline and a long list of significant changes.

Security updates have been issued by Debian (firefox-esr, fusiondirectory, ocsinventory-server, php-cas, and thunderbird), Fedora (dav1d, perl-CPAN, and yt-dlp), Red Hat (python39:3.9 and python39-devel:3.9), Slackware (mozilla), SUSE (prometheus-ha_cluster_exporter and prometheus-sap_host_exporter), and Ubuntu (ghostscript, linux-azure, linux-intel-iotg, linux-intel-iotg-5.15, and ruby-doorkeeper).

Linus has released 6.5-rc1 and closed themerge window for this release.

After an initial foray into the ways that open-source software has failedto live up to its early hype,this DigitalAntiquarian article covers the history of rogue-like games in greatdetail.

Over the years, the kernel has developed a number of deferred-executionmechanisms to take care of work that cannot be done immediately. For many(or most) needs, the workqueuesubsystem is the tool that developers reach for first. Workqueuestook their current form over a dozen yearsago, but that does not mean that there are not improvements to be made.Two sets of patches from Tejun Heo show the pressures being felt by theworkqueue subsystem and the solutions that are being tried - with varyingdegrees of success.

Security updates have been issued by Debian (debian-archive-keyring, libusrsctp, nsis, ruby-redcloth, and webkit2gtk), Fedora (firefox), Mageia (apache-ivy, cups, curaengine, glances, golang, keepass, libreoffice, minidlna, nodejs, opensc, perl-DBD-SQLite, python-setuptools, python-wheel, skopeo/buildah/podman, systemd, testng, and webkit2), SUSE (bind), and Ubuntu (Gerbv, golang-websocket, linux-gke, linux-intel-iotg, and linux-oem-5.17).

The Fedora project is considering aFedora40 change proposal to add limited, opt-out telemetry to theworkstation edition. The proposal is detailed; it is clear that thedevelopers involved understand that this will be a hard sell in thatcommunity.

In the first of two combined BPF and filesystem sessions at the2023 Linux Storage, Filesystem,Memory-Management and BPF Summit, Hou Tao introduced his BPF iteratorsfor filesystem information. Iterators forBPF are a relatively recent addition to the BPF landscape; they helpBPF programs step through kernel data structures in a loop-like manner, butwithout running afoul of the BPF verifier, which is notoriously hard toconvince about loops.

The transition to folios has transformedthe memory-management subsystem in a number of ways, but has also resultedin a lot of code churn that has not been welcomed by all developers. Asthis work proceeds, though, some of the benefits from it are beginning tobecome clear. One example may well be in the handling of anonymous memory,as can be seen in a pair of patch sets from Ryan Roberts.

Security updates have been issued by Debian (golang-yaml.v2, kernel, and mediawiki), Fedora (kernel and picocli), SUSE (bind and python-sqlparse), and Ubuntu (cpdb-libs).

The LWN.net Weekly Edition for July 6, 2023 is available.

The6.4.2,6.3.12,6.1.38, and5.15.120stable kernel updates have all been released; each contains another set ofimportant fixes.

The i_versionfield in structinodeis meant to track changes to the data or metadata of a file. There aresome problems with the way thati_version is being handled in the kernel, so Jeff Layton led a filesystem session at the2023 Linux Storage, Filesystem,Memory-Management and BPF Summit to discuss them and what to doabout them. For the most part, there are solutions in the works that willresolve most of the larger issues.

Ruihan Li has discloseda significant vulnerability introduced into the 6.1 kernel:

Termux is an Android app thatprovides a Linux environment and terminal emulator for such devices. Mostcommand-line software can be used quite easily with Termux, and GUI software can be run by installing a few extra apps. It is an excellentoption for Android users who want to run Linux software occasionally on adevice more portable than a laptop but do not want to use a dedicated Linuxphone due to the cost or limitations of such devices.

The LXD container-management system is no longer a part of the linuxcontainers.org project:

Security updates have been issued by Fedora (firefox and python-reportlab), Slackware (mozilla), SUSE (dnsdist, grpc, protobuf, python-Deprecated, python-PyGithub, python-aiocontextvars, python-avro, python-bcrypt, python-cryptography, python- cryptography-vectors, python-google-api-core, pyt, kernel, kubernetes1.18, libdwarf, python311, qt6-base, rmt-server, and virtualbox), and Ubuntu (containerd, firefox, and python-django).

Joe "Zonker" Brockmeier has been a part of the Linux community for decades;he is now using that experience to write a series on "Red Hat and the CloneWars". The first two episodes were RedHat and the Clone Wars and Ahistory of the early 2000s Linux landscape; the latest is Thedawn of CentOS:

Version115 of the Firefox browser has been released. New features includesupport for hardware video decoding on Intel GPUs on Linux and a new"close" option on the tab-manager dropdown. This release is also the endof the line for Windows7 and8 support, and for macOS 10.12,10.13, and 10.14 support as well.

Chuck Lever led a filesystem session at the2023 Linux Storage, Filesystem,Memory-Management and BPF Summit on the Linux NFS server, which is alsoknown as NFSD. He wanted to talk about converting the network filesystemto use iomap; that kind ofconversionwas the topic of the previous session atthe summit. Beyond that, he wanted to discuss using folios, which has beena frequent topic at recent LSFMM+BPF gatherings, including this year.

Security updates have been issued by Debian (ghostscript), Fedora (apache-ivy, chromium, golang-github-schollz-croc, golang-github-schollz-mnemonicode, and webkitgtk), SUSE (amazon-ecs-init, dnsdist, libcap, python-tornado, terraform, and xmltooling), and Ubuntu (imagemagick, openldap, php7.4, php8.1, and screen).

The C language is expressive in many ways, but it still does not have waysto express many of the relationships between fields in a data structure.That gap can be at least partially filled, though, if one is willing tocreate and use non-standard extensions. The adoption of of thoseextensions, in the form of the __counted_by() macro, has beenmerged for the 6.5 kernel release, even though the compiler feature itdepends on has not yet been finalized.

Version 5.38.0 of the Perl language is out. "Perl 5.38.0 representsapproximately 12 months of development since Perl 5.36.0 and containsapproximately 290,000 lines of changes across 1,500 files from 100authors." Significant changes include a new class feature,Unicode 15.0 support, a new API for hooking into functions, and more; seethe5.38.0 perldelta page for details.

Security updates have been issued by Debian (cups, gst-plugins-bad1.0, gst-plugins-base1.0, gst-plugins-good1.0, python3.7, and yajl), Fedora (chromium, kubernetes, pcs, and webkitgtk), Scientific Linux (open-vm-tools), SUSE (iniparser, keepass, libvirt, prometheus-ha_cluster_exporter, prometheus-sap_host_exporter, rekor, terraform-provider-aws, terraform-provider-helm, and terraform-provider-null), and Ubuntu (python-reportlab and vim).

The6.4.1,6.3.11, and6.1.37stable kernels have been released; each contains another set of importantfixes.

The first days of the 6.5 merge window have been a bit calmer than usual,with "only" 4,000 non-merge changesets having been pulled into the mainlinerepository. Those changesets include a fair amount of significant work,though. Read on for LWN's summary of the first set of changes merged forthe next major kernel release.

The Register reportsfrom Jii Benc's DevConf.cz talk on the making of the CentOS Streamkernel.

Security updates have been issued by Debian (docker-registry, flask, systemd, and trafficserver), Fedora (moodle, python-reportlab, suricata, and vim), Red Hat (go-toolset and golang, go-toolset-1.19 and go-toolset-1.19-golang, go-toolset:rhel8, open-vm-tools, python27:2.7, and python3), SUSE (buildah, chromium, gifsicle, libjxl, sqlite3, and xonotic), and Ubuntu (linux, linux-allwinner, linux-allwinner-5.19, linux-aws, linux-aws-5.19, linux-azure, linux-gcp, linux-gcp-5.19, linux-hwe-5.19, linux-ibm, linux-kvm, linux-lowlatency, linux-oracle, linux-raspi, linux-starfive, linux-starfive-5.19, linux, linux-aws, linux-aws-5.15, linux-aws-5.4, linux-azure, linux-azure-5.15, linux-azure-5.4, linux-azure-fde-5.15, linux-bluefield, linux-gcp, linux-gcp-5.15, linux-gcp-5.4, linux-gke, linux-gke-5.15, linux-gkeop, linux-gkeop-5.15, linux-hwe-5.15, linux-hwe-5.4, linux-ibm, linux-ibm-5.4, linux-kvm, linux-lowlatency, linux-lowlatency-hwe-5.15, linux-nvidia, linux-oracle, linux-oracle-5.15, linux-oracle-5.4, linux-raspi, linux-raspi-5.4, and linux-oem-6.1).

The Emacs editor is not tied to the Linux kernel; indeed, it was createdsome years before Linux existed. The Emacs code base is intended to beportable, and the editor runs, with varying levels of support, on a widevariety of systems. Recently, an energetic developer has worked to extendthe set of supported systems to Android; the result is a working port, butwhether that port will be accepted into the Emacs mainline is the topic ofongoing conversation.

Security updates have been issued by Debian (chromium and maradns), SUSE (iniparser, kubernetes1.23, python-reportlab, and python-sqlparse), and Ubuntu (accountsservice and linux, linux-aws, linux-aws-hwe, linux-azure, linux-azure-4.15, linux-dell300x, linux-gcp, linux-gcp-4.15, linux-hwe, linux-kvm, linux-oracle, linux-raspi2, linux-snapdragon).

The LWN.net Weekly Edition for June 29, 2023 is available.

JupyterLab is aweb-based development environment widely used by data scientists,engineers, and educators for data visualization, data analysis,prototyping, and interactive learning materials. The Jupyter community has recently announced therelease of JupyterLab4.0, introducing lots of new features and performanceimprovements to enhance its capabilities both in research and educationalsettings.

The6.3.10,6.1.36,5.15.119,5.10.186,5.4.249,4.19.288, and4.14.320stable kernels have all been released; each contains another set ofimportant fixes.

Security updates have been issued by Mageia (docker-docker-registry, libcap, libx11, mediawiki, python-requests, python-tornado, sofia-sip, sqlite, and xonotic), Red Hat (kernel, kernel-rt, kpatch-patch, libssh, libtiff, python27:2.7, python39:3.9, python39-devel:3.9, ruby:2.7, sqlite, systemd, and virt:rhel, virt-devel:rhel), SUSE (bind, cosign, guile1, lilypond, keepass, kubernetes1.24, nodejs16, nodejs18, phpMyAdmin, and sqlite3), and Ubuntu (etcd).

A discussion that largely centered around the documentation ofiomap, which provides a block-mapping interface for modern filesystems,was led by Luis Chamberlain at the2023 Linux Storage, Filesystem,Memory-Management and BPF Summit. There is an ongoing process ofconverting filesystems to use iomap, in order to leave buffer heads behind and to better support folios, sothe intent was to get feedback on the documentation from developers who areworking on those conversions. One of the concrete outcomes of the sessionwas a plan to move that documentation from its current location on theKernelNewbies wiki intothe kernel documentation.

Faith Ekstrand has providedan update on the status of the NVKVulkan driver for NVIDIA GPUs.

Security updates have been issued by Debian (c-ares and libx11), Fedora (chromium and kubernetes), Red Hat (python3 and python38:3.8, python38-devel:3.8), and SUSE (amazon-ssm-agent, kernel, kubernetes1.24, libvirt, nodejs16, openssl-1_1, and webkit2gtk3).

Red Hat's Mike McGrath respondsto the many criticisms aimed at the company since it changed its policyregarding RHEL source code.

The 6.4 kernel was releasedon June25 after a nine-week development cycle. By that point, 14,835non-merge changesets had been pulled into the mainline kernel, a slightincrease from 6.3 (14,424 changesets) but still lower than many otherdevelopment cycles. As usual, LWN has taken a look at those changesets,who contributed them, and what the most active developers were up to.