The 5.4-rc6 kernel prepatch is out fortesting. "There's no particular area or outstanding issue that isworrisome, but if things don't calm down this week, I suspect we'll belooking at one of those releases when we have an rc8. We'll see how thingsevolve here over the next couple of weeks."
The kernel project's email-based development process is well establishedand has some strong defenders, but it isalso showing its age. At the 2019 KernelMaintainers Summit, it became clear that the kernel's processes aremuch in need of updating, and that the maintainers are beginning tounderstand that. It is one thing, though, to establish goals for animproved process; it is another to actually implement that process andconvince developers to use it. At the 2019Open Source Summit Europe, a group of 20 or so maintainers anddevelopers met in the corner of a noisy exhibition hall to try to work out what some ofthe first steps in that direction might be.
The long discussion on changing the Pythonproject's release cadence has come to a conclusion: the project will now bereleasing new versions on an annual basis. See PEP 602 for thedetails on how it is expected to work.
Security updates have been issued by CentOS (firefox, sudo, and thunderbird), Debian (libarchive and qtbase-opensource-src), Oracle (php), Red Hat (php, rh-php71-php, and rh-php72-php), Scientific Linux (firefox and php), and SUSE (kernel and samba).
Steven Rostedt has been a part of the Linux kernel tracing community formost of its existence, it seems. He was the developer of ftrace,which was one of the early mainline additions for tracing. There are nowmany tracing facilities in the kernel. At the 2019Open Source Summit Europe in Lyon, France, Rostedt wanted to present an ideathat he has been thinking about for a long time: a unified tracing platformto provide access to all of the kernel tracing facilities from user-space applications.
Security updates have been issued by Debian (imapfilter, libvncserver, and pam-python), Fedora (tcpdump), Mageia (file, graphviz, kernel, and php, pcre2), openSUSE (nfs-utils), Red Hat (heketi and samba), Scientific Linux (thunderbird), SUSE (libtomcrypt, php7, and runc), and Ubuntu (apport, libarchive, libidn2, samba, and whoopsie).
Fedora Magazine announces therelease of Fedora 31. This release includes the Fedora Toolbox forlaunching and managing personal workspace containers. The Fedora Editionsinclude Workstation, Server, with CoreOS and IoT in a previewstate. Alternate architectures include ARM AArch64, Power, andS390x. However the 32-bit only i686 system has been dropped. The releasenotes contain additional information.
Back in March, we looked at a discussionand Python Enhancement Proposal (PEP) for a new dictionary "addition"operator forPython. The discussion back then was lively and voluminous, but the PEP needed someupdates and enhancements in order to proceed. That work has now been doneand a postabout the revisedPEP to the python-ideas mailing list has set off another mega-thread.
Stable kernels 5.3.8, 4.19.81, 4.14.151, 4.9.198, and 4.4.198 have been released. They all containimportant fixes throughout the tree and users should upgrade.
Security updates have been issued by Debian (php7.0, php7.3, ruby-loofah, and spip), Fedora (proftpd), openSUSE (lz4 and sysstat), Red Hat (chromium-browser, jss, kernel, kernel-alt, kpatch-patch, pango, polkit, sudo, systemd, and thunderbird), SUSE (graphite-web, python3, and samba), and Ubuntu (php5, php7.0, php7.2, php7.3, and samba).
The BPF in-kernel virtual machine hasbrought a new set of capabilities to a number of functional areas in thekernel, including, significantly, tracing.Since BPF programs run in the kernel, much effort goes into ensuring thatthey will not cause problems for the running system;to that end, the BPF verifier checks every possible aspect of each BPF program'sbehavior to ensure that it is safe to run in the kernel — with one notableexception. With a patch set titled "revolutionizebpf tracing", Alexei Starovoitov aims to close that loophole andeliminate a set of potential problems in a widely used class of BPFprograms.
A long-anticipated move has finally been madeofficial: the KernelCIcontinuous-integration project has found a new home under the LinuxFoundation umbrella. "The primary goal of KernelCI is to use an opentesting philosophy to improve the quality, stability and long-termmaintenance of the Linux kernel. Expected improvements to the platformunder the Linux Foundation include improved LTS kernel testing andvalidation; consolidation of existing testing initiatives; quality-of-lifeimprovements to the current service; expanded compute resources; andincreased pool of hardware to be tested. In the long-term, members expectto modernize the architecture; test software beyond the Linux kernel; anddefine testing standards and engage in cross-project collaboration."
The 5.4-rc5 kernel prepatch is out fortesting."So we have a bit more fixes than normal during this stage, but nothinglooks very strange, and the diffstat looks _mostly_ flat (with thecpufrequency power-QoS and io_uring changes looking a bit bigger)which is my sign for 'small changes all over'". The codename haschanged again; now it's "Kleptomanic Octopus", suggesting some interestingencounters in Linus's latest diving outing.
The io_uring mechanism is a relatively newinterface for asynchronous I/O; it first appeared in the 5.1 kernel inMay. Since then, though, it has quickly grown in capabilities and inusers; now it appears that it is outgrowing some of the kernelinfrastructure that supports it. Thus, we have a proposal from Jens Axboe(the io_uring maintainer) for a newworkqueue subsystem for io_uring that hints at some interesting plansfor the future.
Security updates have been issued by Debian (firefox-esr), Gentoo (php), Oracle (firefox), Scientific Linux (sudo), and SUSE (accountsservice, binutils, nfs-utils, and xen).
The GNU Project was created by RichardStallman in 1983 to further his goal of developing an entirely freeoperating system — a goal that seemed impossibly ambitious at the time.Stallman has recently resigned from some of his roles, but asof this writing his personal site stillleads off with this proclamation: "I continue to be the ChiefGNUisance of the GNU Project. I do not intend to stop any time soon". Within the project itself,though, it has become clear that this intention lacks universal support.We appear to be seeing the beginning of a governance transition for thisvenerable project.
Security updates have been issued by Debian (file), Mageia (bind, chromium-browser-stable, java-1.8.0-openjdk, libsndfile, mediawiki, and virtualbox), Oracle (firefox), Red Hat (firefox and sudo), Scientific Linux (firefox and OpenAFS), SUSE (kernel, lz4, rust, and xen), and Ubuntu (firefox).
Back in July, Linus Torvalds merged a patchin the 5.3 merge windowthat added the PREEMPT_RT option to the kernel build-time configuration.That was meant as a signal that the realtime patch set was moving from its longtime status asout-of-tree code to a fully supported kernel feature. As the code behindthe configuration option makes its way into the mainline, some friction canbe expected; we are seeing a bit of that now with respect to the BPF subsystem.
There has been discussion about the release cadence of Python for a coupleof years now. The 18-month cycle between major releases of the languageis seen by some core developers as causingtoo muchdelay in getting new features into the hands of users. Now there are twocompeting proposals for ways to shorten that cycle, either to one year orby creating a rolling-release model. In general, the steering councilhas seemed inclined toward making some kind of release-cycle change—one ofthose Python Enhancement Proposals (PEPs) may well form the basis ofPython's release cadence moving forward.
Security updates have been issued by Arch Linux (go, go-pie, pacman, and xpdf), CentOS (java-1.7.0-openjdk, java-1.8.0-openjdk, java-11-openjdk, and patch), openSUSE (gcc7), Red Hat (firefox, kernel, and qemu-kvm-rhev), Slackware (mozilla), SUSE (kernel, libcaca, openconnect, python, sysstat, and zziplib), and Ubuntu (libxslt, linux-azure, and linux-lts-xenial, linux-aws).
Tails (The Amnesic Incognito LiveSystem) is, as the spelled out name implies, a privacy focuseddistribution, designed to run from removable media. Version 4.0 has been released. "We are especially proud to present you Tails 4.0, the first version of Tails based on Debian 10 (Buster). It brings new versions of most of the software included in Tails and some important usability and performance improvements. Tails 4.0 introduces more changes than any other version since years."
Version70 of the Firefox web browser is out. The headline features include anew password generator and a "privacy protection report" showing userswhich trackers have been blocked. "Amazing user features and protections aside, we’ve also got plentyof cool additions for developers in this release. These include DOMmutation breakpoints and inactive CSS rule indicators in the DevTools,several new CSS text properties, two-value display syntax, and JS numericseparators." See the releasenotes for more details.
Security updates have been issued by CentOS (jss and kernel), Debian (libpcap, openjdk-8, and tcpdump), Fedora (java-11-openjdk), openSUSE (libreoffice), Oracle (java-1.7.0-openjdk), Red Hat (java-1.7.0-openjdk, python, and wget), Scientific Linux (java-1.7.0-openjdk), SUSE (ceph, ceph-iscsi, ses-manual_en, dhcp, openconnect, and procps), and Ubuntu (exiv2, linux, linux-aws, linux-azure, linux-gcp, linux-kvm, linux-raspi2, linux, linux-aws, linux-kvm, linux-raspi2, linux-snapdragon, linux-hwe, linux-azure, linux-gcp, linux-gke-5.0, linux-snapdragon, and uw-imap).
Rothschild Patent Imaging LLC filed a patentsuit against the GNOME Foundation in September, asserting a violationin the Shotwell photo manager. GNOME has now goneon the counterattack, questioning the validity of the patent and whetherit applies to Shotwell at all. There is also an unspecified counterclaimto strike back against Rothschild. "We want to send a message to allsoftware patent trolls out there — we will fight your suit, we will win,and we will have your patent invalidated. To do this, we need yourhelp."
When a kernel subsystem maintainer has a set of commits to send up thechain toward the mainline, the git request-pullcommand is usuallythe right tool for the job. But various maintainers have noticed over theyears that this command can sometimes generate confusing results whenconfronted with anything but the simplest of histories. A briefconversation on the linux-kernel mailing list delved into why thissituation comes about and what maintainers can do in response.
Security updates have been issued by Debian (aspell, graphite-web, imagemagick, mediawiki, milkytracker, nfs-utils, and openjdk-11), Fedora (kernel, kernel-headers, kernel-tools, mediawiki, and radare2), openSUSE (dhcp, libpcap, lighttpd, and tcpdump), Scientific Linux (java-1.8.0-openjdk), Slackware (python), SUSE (bluez, kernel, and python-xdg), and Ubuntu (aspell).
The 5.4-rc4 kernel prepatch is out fortesting. "This release cycle remains pretty normal. In fact, the rc's have beena bit on the smaller side of the average of the last few releases, andrc4 continues this, if only barely."
kmalloc() is a frequently used primitive for the allocation ofsmall objects in the kernel. During the 2019Linux Storage, Filesystem, and Memory Management Summit, VlastimilBabka led a session about the unexpectedalignment problems developers face when using this function. After a fewmonths he has come back with the secondversion of a patch set implementing a natural alignment guarantee forkmalloc(). From the strong opposition it facedinitially, it seemed that the change would not get accepted. However, itended up in Linus Torvalds's tree. Let's explore what happened.
After more than two years of development, the Linux trace toolkit next generation (LTTng)project has released version 2.11.0 of the kernel and user-space tracingtool. The release covers the LTTng tools, LTTng user-space tracer, andLTTng kernel modules. It includes a number of new features that aredescribed in the announcement including session rotation, dynamic user-space tracing,call-stack capturing for the kernel and user space, improved networkingperformance, NUMA awareness for user-space tracing buffer allocation, andmore. "The biggest feature of this release is the long-awaited sessionrotation support. Session rotations now allow you to rotate anongoing tracing session much in the same way as you would rotatelogs.The 'lttng rotate' command rotates the current trace chunk ofthe current tracing session. Once a rotation is completed, LTTng doesnot manage the trace chunk archive anymore: you can read it, modify it,move it, or remove it.Because a rotation causes the tracing session’s current sub-buffersto be flushed, trace chunk archives are never redundant, that is, theydo not overlap over time, unlike snapshots.Once a rotation is complete, offline analyses can be performed onthe resulting trace, much like in 'normal' mode. However, the bigadvantage is that this can be done without interrupting tracing, andwithout being limited to tools which implement the 'live' protocol."
Greg Kroah-Hartman has announced the release of the 5.3.7, 4.19.80, 4.14.150, 4.9.197, and 4.4.197 stable kernels. All five containimportant fixes throughout the kernel tree, as usual. Users of thoseseries should upgrade.
Security updates have been issued by Debian (poppler, sudo, and wordpress), Oracle (java-1.8.0-openjdk), Red Hat (java-1.8.0-openjdk), Scientific Linux (java-1.8.0-openjdk, java-11-openjdk, and kernel), and SUSE (kernel and postgresql10).
Ubuntu has announced the release of 19.10 "Eoan Ermine" in desktop and server editions as well as all of the different flavors: Ubuntu Budgie, Kubuntu, Lubuntu, Ubuntu Kylin, Ubuntu MATE,Ubuntu Studio, and Xubuntu. "The Ubuntu kernel has been updated to the 5.3 based Linux kernel, andour default toolchain has moved to gcc 9.2 with glibc 2.30. Additionally,the Raspberry Pi images now support the new Pi 4 as well as 2 and 3.Ubuntu Desktop 19.10 introduces GNOME 3.34 the fastest release yet withsignificant performance improvements delivering a more responsiveexperience. App organisation is easier with the ability to drag and dropicons into categorised folders and users can select light or dark Yarutheme variants. The Ubuntu Desktop installer also introduces installingto ZFS as a root filesystem as an experimental feature." More information can also be found in the release notes.
The final days of the 5.3 kernel development cycle included an extensive discussion of thegetrandom() API and the reversion of an ext4 improvement thatwas indirectly causing boot hangs due to a lack of entropy. Blockingfilesystem improvements because they are too effective is clearly not agood long-term development strategy for the kernel, so there was aconsensus that some sort of better solution had to be found. What was lackingwas an idea of what that solution should be. It is thus surprising thatthe problem appears to have been dealt with in 5.4 with little in the wayof dissent or disagreement.
Google has announcedversion 1.0 of its Bazel buildsystem. "A growing list of Bazel users attests to the widespread demand for scalable, reproducible, andmulti-lingual builds. Bazel helps Google be more open too: several largeGoogle open source projects, such as Angular and TensorFlow, useBazel. Users have reported 3x test time reductions and 10x faster buildspeeds after switching to Bazel."
Security updates have been issued by Arch Linux (sudo), Debian (libsdl1.2 and libsdl2), Mageia (e2fsprogs, kernel, libpcap and tcpdump, nmap, and sudo), openSUSE (GraphicsMagick and sudo), Oracle (java-1.8.0-openjdk, java-11-openjdk, jss, and kernel), Red Hat (java-1.8.0-openjdk and java-11-openjdk), Scientific Linux (jss), SUSE (gcc7 and libreoffice), and Ubuntu (leading to a double-free, libsdl1.2, and tiff).
When last we looked in on the progress ofthe WireGuard VPN tunnel toward themainline kernel, it seemed like the main sticking point had been overcome. The Zinc cryptography API used by WireGuard wasgenerally seen as a duplication of effort with the existing kernelcryptographic algorithms, so an effort to rework Zinc to use that existingcode seemed destined to route around that problem and bring WireGuard tothe mainline. In the six months since then, though, things have gonefairly quiet in WireGuard-land; that all changed based on a conversation atthe recent Kernel Recipesconference in Paris.
The problems with field-programmablegate arrays (FPGAs) is not exactly an obvious talk topic for agraphics-related conference like the 2019 X.Org Developers Conference (XDC). BenWidawsky acknowledged that, but said that he sees parallels in thesituation with FPGA support in the free-software world and the situation withgraphics hardware support in the past. It is his hope that the tools fordeveloping with FPGAs can make the same journey that graphics drivers havemade over the last two decades or so.
Security updates have been issued by Debian (apache2 and unbound), Fedora (opendmarc, runc, and sudo), openSUSE (epiphany, GraphicsMagick, and libopenmpt), Oracle (kernel and sudo), Red Hat (java-1.8.0-openjdk, jss, kernel, kernel-rt, and kpatch-patch), SUSE (crowbar-core, crowbar-openstack, grafana, novnc, openstack-keystone, openstack-neutron, openstack-neutron-lbaas, openstack-nova, openstack-tempest, python-pysaml2, python-urllib3, rubygem-chef, rubygem-easy_diff, sleshammer, libpcap, sudo, and tcpdump), and Ubuntu (aspell and libsdl1.2).
The pull request changing the name of Perl 6 to Raku has beenmerged. See thefull text for more information. "This document describes the stepsto be taken to effectuate a rename of 'Perl 6' to 'Raku', as described inissue #81. It does not pretend to be complete in scope or in time. Tochange a name of a project that has been running for 19+ years will taketime, a lot of effort and a lot of cooperation. It will affect people inforeseen and unforeseen ways." (Thanks to Sean Whitton)
Security updates have been issued by Debian (sudo and xtrlock), openSUSE (sudo), Red Hat (Single Sign-On), Slackware (sudo), SUSE (binutils, dhcp, ffmpeg, kernel, kubernetes-salt, sudo, and tcpdump), and Ubuntu (sudo).
The KDE project has announced therelease of version 5.17 of the Plasma desktop environment."Night Color, the color-grading system that relaxes your eyes whenthe sun sets, has landed for X11. Your Plasma desktop also recognizes whenyou are giving a presentation, and stops messages popping up in the middleof your slideshow. If you are using Wayland, Plasma now comes withfractional scaling, which means that you can adjust the size of all yourdesktop elements, windows, fonts and panels perfectly to your HiDPImonitor."
Version3.8.0 of the Python language has been released. New features includethe controversial assignment expressions,positional-only arguments,the Vectorcallmechanism, and more; see the what's new in Python3.8 document for more information.
Version7.2 of PyPy, an implementation of the Python language, is out. Withthis release, Python 3.6 support is deemed ready: "This releaseremoves the 'beta' tag from PyPy3.6. While there may still be some smallcorner-case incompatibilities (around the exact error messages inexceptions and the handling of faulty codec errorhandlers) we are happywith the quality of the 3.6 series and are looking forward to working on aPython 3.7 interpreter."
Race conditions can be some of the trickiest bugs to find. The resultingproblems can be subtle, and reproducing the problem in order to track itdown can be difficult or impossible; often code inserted to narrow down arace condition will cause it to stop manifesting entirely. A tool that canfind race conditions automatically would thus be a valuable thing for thekernel community to have. In late September, Marco Elver announceda tool called KCSAN (the Kernel Concurrency Sanitizer) that doesexactly that — and which has already found a number of real problems.
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