Linux Kernel News Archives

With the Linux 6.11 kernel merge window wrapping up this weekend, I've begun "kicking the tires" on the new kernel that will then see the weekly release candidates over the next two months. For some initial Linux 6.10 vs. 6.11 Git benchmarking on an AMD Ryzen Threadripper workstation, the new kernel is appearing fit and offering some nice performance gains in a few areas.

Miguel Ojeda has sent out the big Rust pull request for the nearly wrapped up Linux 6.11 merge window. This contains all of the latest Rust programming language infrastructure now ready for the mainline kernel.

Going back two years has been the effort for adding getrandom() to the vDSO in order to enhance the performance. This work has yielded as much as 15x the performance in showing very fast while being secure user-space RNG needs. A few weeks back Linus Torvalds was unconvinced by adding getrandom() to the vDSO, but after going back through the patches he gave it another go. Today the work has managed to be mainlined for Linux 6.11.

Andrew Morton on Sunday sent in his "MM" pull requests for Linux 6.11 of the areas of the kernel he manages.

Back in March were a set of patches to the Linux kernel's XZ embedded compression implementation with the project having switched from public domain to the BSD Zero Clause License along with other changes to update that in-tree code. Since then the notorious XZ backdoor situation was discovered in the upstream XZ project. With those major issues behind, Lasse Collin today sent out an updated set of patches for updating the in-tree XZ code for the Linux kernel.

The crypto subsystem updates have landed for the Linux 6.11 kernel.

The SLAB pull request landed in Linux 6.11 Git on Thursday with kmem_buckets-based hardening of kernel memory allocations.

While Rust is viewed as a memory safe and robust programming language, there is the "unsafe" keyword within Rust that can be used for unsafe code that grants "unsafe superpowers" for the language. As dealing with Rust at low-levels as the Linux kernel can lead to needing to use "unsafe" Rust at times, a documentation standard has been proposed for dealing with such code inside the kernel.

Linus Torvalds began the Linux 6.11 merge window yesterday by merging some of his own feature code for this next kernel version.

Following last night's release of the Linux 6.10 kernel, the FSF LA developers have released GNU Linux-libre 6.10-gnu as their downstream kernel flavor that strips out the ability to load binary-only kernel modules and the ability to load non-free firmware/microcode into open-source drivers, among other alterations in the name of software freedom.

As anticipated the Linux 6.10 kernel was released as stable a few minutes ago by Linus Torvalds.

With Linux 6.10 expected to be released in the coming hours, in turn the Linux 6.11 merge window will open tomorrow unless there is any last-minute v6.10 release delay. With that said, here's a look at some of the features you can likely expect to see for this next kernel version.

Linux 6.10 stable should be released later today. It's been a fairly calm week in the kernel world and thus Linus Torvalds will most likely opt for tagging v6.10 as opposed to doing a v6.10-rc8 extra release candidate. So with Linux 6.10 likely upon us, here's a reminder about some of the most interesting changes in this new kernel release.

Linus Torvalds just released Linux 6.10-rc7 as the latest weekly release candidate of the forthcoming Linux 6.10 kernel.

As part of the memory management changes expected to be merged for the upcoming Linux 6.11 cycle is allowing more fine-tuned control over the swappiness setting used to determine how aggressively pages are swapped out of physical system memory and into the on-disk swap space.

It's been nearly one decade since Intel began working on 5-level paging support for the Linux kernel to allow for greater virtual and physical address space with expanding memory sizes. The 5-level paging kernel-side bits were upstreamed back in Linux 4.12 in 2017 and enabled by default since 2019 with Linux 5.5. Intel CPUs for a while (since Ice Lake) have supported 5-level paging and AMD CPUs too since Zen 4. The Linux kernel may move to unconditionally enabling 5-level paging support for x86_64 kernel builds.

Linux 6.10 introduces DRM Panic for providing a new panic screen in case of kernel errors and situations where the VT support may be disabled. This new kernel functionality is akin to Windows' Blue Screen of Death or thanks to open-source can be adapted to take on other forms such as a black screen of death and conveying monochrome logos rather than ASCII art. New patches provide for the ability to show QR codes of error messages within the DRM Panic screens.

For years Meta/Facebook has been exploring using BOLT with the Linux kernel to optimize the layout of the Linux kernel binary. Since BOLT was upstreamed into LLVM, they've continued work around BOLT'ing the kernel. There is now a public guide for carrying out a BOLT-optimized Linux kernel build and roughly 5% better system performance to expect from such an optimized kernel.

The Linux 6.10 kernel cycle continues trending along nominally and giving hope for an on-time stable kernel release in two weeks.

The DRM Panic handler in Linux 6.10 that is used for presenting a visual error message in case of kernel panics and similar when CONFIG_VT is disabled continues seeing new features. This is the Linux equivalent to Windows' Blue Screen of Death or in the case of DRM Panic can also be a black screen of death. With Linux 6.11, the DRM Panic display can now handle monochrome logos.

Linus Torvalds has just tagged Linux 6.10-rc5 as the newest weekly test release leading up to the Linux 6.10 stable release by mid-July.

Red Hat engineer Leonardo Bras has laid out a proposal for QPWs, or "Queue PerCPU Work", as a better means of handling per-CPU operations within the Linux kernel especially for real-time (RT) workloads.

With some Linux users not liking the recently showcased new Linux "Blue Screen of Death" for kernel panics, Red Hat engineer Javier Martinez Canillas who has been one of those involved in the new DRM Panic infrastructure showed that it can also be a "black screen of death" if so desired.

Another weeks worth of random DRM-Misc-Next changes have been queued ahead of next month's Linux 6.11 merge window.

Sent out last month were the very preliminary Rust-written Nova GPU kernel driver patches for this in-development Direct Rendering Manager driver for open-source NVIDIA GPU support for RTX 20 / Turing GPUs and newer by leveraging the NVIDIA GPU System Processor (GSP). Sent out this week is the second iteration of the stubbed Nova kernel driver and the associated Rust language DRM subsystem abstractions.

The Linux kernel "FORCE_NR_CPUS" Kconfig option has been around a few years to force the number of CPU cores the kernel expects in order to allow for better compiler optimizations. When building a kernel targeted for a specific device/platform with a given number of CPU cores, the compiler can optimize CPU mask routines and shrink the size of the resulting kernel image rather than having to accommodate up to a dynamic upper-limit for the number of CPU cores to be found at boot time. Linus Torvalds himself has turned to demoting this CONFIG_FORCE_NR_CPUS option further to avoid confusion.

Linus Torvalds as the father of the Linux kernel set aside some time this Father's Day to release Linux 6.10-rc4.

After being talked about for years of DRM panic handling and coming with a "Blue Screen of Death" solution for DRM/KMS drivers, Linux 6.10 is introducing a new DRM panic handler infrastructure for being able to display a message when a panic occurs. This is especially important for those building a kernel without VT/FBCON support where otherwise viewing the kernel panic message isn't otherwise easily available.

The extensible scheduler "sched_ext" code has proven quite versatile for opening up better Linux gaming performance, more quickly prototyping new scheduler changes, Ubuntu/Canonical has been evaluating it for pursuing a more micro-kernel like design, and many other interesting approaches with it. Yet it's remained out of tree but that is now changing with the upcoming Linux 6.11 cycle.

Going back just under two years was the propsal for adding getrandom() to the vDSO in the quest to achieve faster performance for obtaining random numbers in user-space. That effort while seemingly simple remains an ongoing and contentious matter.

Linus Torvalds just announced the release of Linux 6.10-rc3 as a rather pleasant week for this stage of the kernel cycle.

The patches recently covered on Phoronix for up to 162% faster AES-GCM encryption/decryption with modern Intel and AMD processors is now queued for introduction in the upcoming Linux 6.11 cycle!

John Ogness of Linutronix today sent out the second iteration of his patches working on threaded printing support for printk() and related rework of that code that is a necessary step before the real-time (RT) kernel patches can be finally mainlined.

With the in-development Linux 6.10 kernel Eric Biggers of Google landed new AES-XTS implementations for much faster performance for Intel/AMD processors via new AES-NI + AVX, VAES + AVX2, VAES + AVX10/256, and VAES + AVX10/512 code paths. Biggers has since begun tackling even better AES-GCM encryption/decryption performance by leveraging a new code path to utilize AVX-512/AVX10 and/or VAES.

Linus Torvalds just released Linux 6.10-rc2 with a busy week's worth of fixes.

Now past the Linux 6.10 merge window, this week brought an initial batch of drm-misc-next changes submitted to the Direct Rendering Manager subsystem's DRM-Next for queuing until the Linux 6.11 merge window opens up in July. The changes this week include a notable addition for the open-source NVIDIA (Nouveau) driver and some improvements for the Intel iVPU driver for their Neural Processing Unit (NPU).

Ahead of today's Linux 6.10-rc2 kerne weekly test release a few "x86/urgent" patches were submitted for addressing some fallout on Intel and AMD processors.

The Linux 6.10-rc1 kernel was just released to top off the Linux 6.10 merge window.

With the memory management "MM" updates merged for the Linux 6.10 there is now NUMA balancing support for multi-size transparent hugepages (THPs). This is yielding some nice performance results and there is also other work in this new kernel around multi-size THPs.

Andrew Morton sent out more patches on Wednesday that have been pulled into the Linux 6.10 kernel. Notable from this latest round of "non-MM" updates is enabling more compiler warnings by default and getting newer AMD GPUs working on the RISC-V architecture.

Greg Kroah-Hartman today sent in the char/misc updates for Linux 6.10 alongside the other areas of the kernel he oversees. Among the char/misc changes is adding the NTSYNC driver that exposes the /dev/ntsync character device for use by the likes of Wine and Valve's Steam Play (Proton). But for Linux 6.10 the driver is effectively "broken" as most of the feature patches have yet to be included.

Introduced last year with the Linux 6.7 kernel was a hardening configuration to allow for "make hardening.config" as an easy way of building a security-hardened Linux kernel with sane defaults. With Linux 6.10 there are some additional security minded features now enabled.

As a small information heads up, the Linux 6.10 kernel will print the number of populated memory slots at boot time to the kernel log as a little helper.

Alongside all of the other pull requests by Ingo Molnar submitted at the start of the week during the opening of the Linux 6.10 merge window were the scheduler updates. As usual, the kernel scheduler work continues to see various tweaks and refinements to enhance its behavior.

While machine check exception (MCE) events tend to be uncommon, a change made by Intel engineers is accommodating the ability in the Linux kernel to store more machine check records for "when things go seriously wrong" on increasingly high core count servers.

The year-long effort to removal the sysctl sentinel for clearing bloat from the kernel and allowing faster build times should be crossing the finish line in Linux 6.10.

Besides Linus Torvalds examining various elements of code he's merging and build testing it on his AMD Ryzen Threadripper workstation and now also testing more on ARM64 with Ampere Altra, he does these days still believe in "dogfooding" and is in fact running the leading-edge Linux kernel code even during the merge window.

The big batch of Direct Rendering Manager (DRM) kernel graphics/display driver updates for the Linux 6.10 merge window were sent out today that includes the new "Panthor" driver for newer ARM Mali/Immortalis graphics processors and the usual hearty assortment of Intel and AMD graphics driver changes.

Linux kernel and Git creator Linus Torvalds is known for his current use of an AMD Ryzen Threadripper workstation as his main system after years of using Intel hardware. The past few years he's also been doing more ARM64 testing now that he has an Apple MacBook using Apple Silicon that serves as a nice travel device and for routinely compiling new ARM64 Linux kernel builds. More recently, his ARM64 Linux testing has increased now that he has a more powerful AArch64 system to complement his collection of routine gear.

The work written about one month ago on Phoronix for much faster AES-XTS on modern Intel/AMD CPUs for speeding up disk and file encryption by as much as 155% with AMD Zen 4 CPUs has been submitted for Linux 6.10! As expected, this work providing new AES-XTS implementations for modern x86_64 processors is going into Linux 6.10 as part of the crypto subsystem updates.