Linux Kernel News Archives

It's been many years since Intel Itanium processors made a convincing story and faced a slow demise over the past decade. While the last of the Itanium 9700 "Kittson" processors shipped in 2021, just two years later now the Linux kernel is already looking at possibly seeing its IA-64 support removed over having no maintainers or apparent users.

While initial Rust code was merged for Linux 6.1, it's not yet used by any kernel drivers or functionality for end-users and the integration and other abstractions for Rust are still being established. With the upcoming Linux 6.3 cycle, more of that Rust groundwork is set to be merged and nearing the point of Rust-written kernel modules/drivers will be able to be upstreamed.

Linus Torvalds just released Linux 6.2-rc8 ahead of the planned Linux 6.2 stable release next Sunday, 19 February.

Upstream kernel developers have begun hitting RAM capacity issues when carrying out large Linux kernel builds with the likes of "allyesconfig" for enabling all possible modules/options. While 32GB of system RAM has been common for developer desktops in recent years, large Linux kernel builds and taking advantage of multiple compile jobs have begun to cross that threshold and leading to out-of-memory behavior. Fortunately, a set of patches to the kernel's objtool is taming the memory use to rein in kernel builds for such scenarios.

Linux 6.1 was widely anticipated to be a Long-Term Support (LTS) kernel with normally the last major release series for the calendar year normally promoted to LTS status. Greg Kroah-Hartman as the Linux stable maintainer went ahead today and formally recognized Linux 6.1 as the 2022 LTS kernel.

Qualcomm's Cloud AI 100 inference accelerator that features up to sixteen cores and focused on AI needs at the edge of data centers continues on a trek toward having mainline Linux kernel support.

After the prior kernel patches had stalled in their review process, last week work was revived on x86_64 parallel CPU bring-up for the Linux kernel to help in booting the kernel faster on larger core count desktops and servers. The results have been promising and over the past few days more test results have flowed in along with other positive commentary that will hopefully this time lead to the work ultimately getting upstreamed.

Linus Torvalds just issued the seventh weekly RC release of Linux 6.2 while the stable kernel debut is expected two weeks from today.

Originally posted two years ago were Linux kernel patches for bringing up of CPU cores in parallel to speed-up the Linux boot process. With the growing core counts of servers and even high-end desktops / HEDT platforms, this parallel bring-up can lead to significant time savings at boot. The work, unfortunately, stalled but has now been revised.

The MSM Direct Rendering Manager (DRM) driver that was started originally as part of the Freedreno effort for open-source, reverse-engineered graphics driver support for Qualcomm Adreno graphics continues flourishing. A number of MSM driver additions -- including new Qualcomm platform support -- is ready to go with the upcoming Linux 6.3 kernel.

A set of 24 Linux kernel patches today wire up the basic ACPI infrastructure support for the RISC-V processor architecture.

Linus Torvalds just released the sixth weekly RC of Linux 6.2 and it's coming in unusually light.

Published back in November were a set of patches for allowing (e)BPF to extend the Linux kernel's scheduler. That interesting work is continuing with Friday having brought a second revision to the patches.

There still is another month to go until the Linux 6.2 kernel is released as stable and in turn kicking off the Linux 6.3 merge window. But from my monitoring in recent weeks, here is an early preview of some of the material expected for the v6.3 kernel based on what's been queuing in the various subsystem "-next" branches or otherwise looking like it should align for the next cycle.

Linus Torvalds just released Linux 6.2-rc5 a day early compared to his usual Sunday ritual as a result of traveling. Due to an uptick in activity this week and the downtime around Christmas / end-of-year holidays, Torvalds is planning on this cycle spanning through Linux 6.2-rc8 before going gold.

A patch worked on by an Intel engineer for batched TLB flushing for page migration with folios is showing some promising results and currently working its way to the mainline kernel.

Today a new drm-misc-next pull request was submitted for DRM-Next of various Direct Rendering Manager changes queuing for Linux 6.3. Most significant with today's pull request is eliminating seven old DRM drivers that are for vintage hardware and these open-source drivers are no longer maintained.

Due to Linus Torvalds traveling later in the day, he's released Linux 6.2-rc4 a half-day early as the latest weekly snapshot of Linux 6.2.

Linus Torvalds released Linux 6.2-rc3 a few hours early today and noted that things are "starting to look a lot more normal" in terms of the code churn for this stage of the Linux 6.2 development cycle now that the holiday period has passed.

The ARIA block cipher devised by South Korean researchers is being sped up by AVX2 and AVX-512 for its Linux kernel implementation.

The Linux 4.9 kernel was released back in 2016 and Greg Kroah-Hartman today issued the final point release for that kernel series with the Long Term Support (LTS) period now expired.

While MGLRU is a nice performance win for the Linux kernel now available when enabling it for v6.1+ kernel builds, during my testing I did encounter a regression around the SVT-AV1 video encode performance at least and a fix is working its way toward mainline.

Those paying close attention to the Linux kernel development may have noticed a small change to how a key Linux developer is marking his kernel patches.

Sent out last year as "request for comments" were two rounds of patches by Google engineer James Houghton for introducing the concept of HugeTLB High Granularity Mapping (HGM) to the Linux kernel. In kicking off the new year, the set of 46 patches in their post-RFC state have been mailed out for review.

With the Linux 6.2 merge window behind us, feature work for the Direct Rendering Manager (DRM) changes targeting now the Linux 6.3 kernel have begun queuing with DRM-Next.

Linus Torvalds just released Linux 6.2-rc2 as the second weekly release candidate for Linux 6.2 following the merge window's closure last week on Christmas.

On New Year's Eve, Greg Kroah-Hartman released a new set of stable kernels with Linux 6.1.2, 6.0.16, and 5.15.86 LTS being the new set.

Merged just over a year ago into the Linux kernel was DAMON as an Amazon-developed solution for monitoring data accesses. In the year since being merged, DAMON has continued to see more functionality added and new users and developers becoming involved with this data access monitoring.

Updated patches were sent out today that aim to reduce the maximum memory usage while compiling the Linux kernel. In turn for memory constrained systems that attempt to compile the kernel this should lead to less swapping and faster build times.

The Restartable Sequences "RSEQ" system call merged a few years ago into the Linux kernel and is now used by the GNU C Library and friends for faster user-space operations on per-CPU data. Now coming next year with Linux 6.3 is set to be some notable additions to the RSEQ support.

Intel engineer Huang Ying sent out a set of patches today to implement batch TLB flushing for page migration within the migrate_pages() function and is showing very promising results.

With the in-development Linux 6.2 kernel there is the new compute accelerator "accel" subsystem/framework as part of the Direct Rendering Manager area. The creation of that new subsystem was pulled together by Intel (Habana Labs) and now their AI accelerator driver is preparing to move from the "char/misc" catch-all to this new subsystem.

Following the two week long Linux 6.2 merge window colliding with Christmas day, Linus Torvalds just released Linux 6.2-rc1 as capping off the merge window and moving on to the testing and bug fixing phase of this release cycle.

The IRQ pull request that was merged early in the Linux 6.2 cycle has a big rework to the Message Signaled Interrupts (MSI) subsystem.

It turns out the hand-written Assembly code providing an optimized string comparison "strcmp" function for the Motorola 68000 (m68k) processor architecture has "always been broken" and only now uncovered at the end of 2022.

Merged last week to Linux 6.2 as part of Andrew Morton's memory management related patches is support within ZRAM for multiple compression streams.

One of the best features to make it into the mainline Linux kernel this year is MGLRU as the Multi-Gen LRU for overhauling the kernel's page reclamation code. The MGLRU code that premiered in Linux 6.1 has been showing off very well in a variety of benchmarks.

The USB and Thunderbolt driver updates were merged a few days ago for the Linux 6.2 kernel with its merge window open until Christmas.

In addition to Linux 6.2 upgrading its Zstd implementation for speedier compression/decompression for in-kernel uses of the Zstandard compression algorithm, this new kernel version is adding another Zstd use-case: compressed debug info sections.

It finally happened! An updated Zstd kernel implementation based on Zstd v1.5 upstream has been merged for the in-development Linux 6.2 to provide better performance and reliability for Zstd compression/decompression use-cases from compressed firmware to transparent file-system compression.

The IBM Power/PowerPC architecture updates were sent out today for the ongoing Linux 6.2 merge window and most significant with this update is the introduction of a new Power-specific qspinlock implementation designed to bolster large system scalability.

In addition to the HID driver updates for the Linux 6.2 kernel that were merged this week, the input subsystem updates also landed this week and were headlined by having several new touchscreen drivers.

The hardware monitoring "HWMON" subsystem updates were merged earlier this week for the ongoing Linux 6.2 merge window.

As a nice Christmas present, code merged today to the Linux 6.2 kernel speeds up a core kernel function by a factor of 715x.

The Linux 6.2 Direct Rendering Manager (DRM) open-source kernel graphics/display driver changes have been merged with a few notable feature additions for users this cycle.

The x86 memory management updates for the Linux 6.2 merge window have been submitted with two primary additions: addressing another "tasty target for attackers" and separately is also landing of Intel's Linear Address Masking (LAM) functionality.

Back in 2020 the Linux kernel added a split-lock detector since when they occur an atomic instruction spanning multiple cache lines and requiring a global bus lock is needed. This has an unfortunate heavy impact on the system and thus the detector was added to report it to the kernel log when a split-lock occurs. But earlier this year starting with Linux 5.19, kernel developers decided to "make life miserable" and intentionally slow down bad behaving apps that abuse split-locks. That in turn has caused problems for some games -- so far select Windows games running under Steam Play -- and thus a new kernel knob is being added to more easily adjust the behavior.

Linus Torvalds just released Linux 6.1 as stable!

Following the recent developer talk of looking to drop SLOB from the Linux kernel, this simple allocator is being deprecated come Linux 6.2.

While Linux 6.1 is introducing many new features, for the Linux 6.2 merge window beginning next week there is a lot more on tap. Linux 6.2 has a lot of exciting additions expected from new low-level software features, continuing to lay more Rust code, new hardware support, stable Intel Arc Graphics support, and a ton more. Here is an early look at some of what is expected.