The release cycle of the Linux kernel continues as 5.19 was released almost three weeks ago, and the developers are now working on the next step: 6.0. Linux kernel 6.0 is now under development and got its first release candidate last week.
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Why is it named Linux kernel 6.0?
After the release of version 5.19 of the Linux kernel, people were expecting 5.20 as the next version. However, Linus Torvalds, developer of the Linux kernel decided to go on with 6.0 as the version number. But this decision was only based on the numbers; the “20” in 5.20 was a too big number, so Linus changed the “5” and it became 6.0. Nothing revolutionary comes with Linux kernel 6.0; it is a usual kernel release.
CPU-related changes
Linux kernel 6.0 delivers some additional fixes for Retbleed vulnerability. AMD Zen 1, Zen 1+, and Zen 2+ CPUs are not fully secured with the IBPB mode; so STIBP is now also available for those CPUs to fully secure the systems. Going on with AMD-related news, the company drops audio drivers, for a platform codenamed “Pink Sardine”. This is a completely new codename; the company also used other fish names for its Ryzen 5000 and Ryzen 6000 series APUs.
Pink Sardine platform is based on the “acp6.2” design; there is no further information about it yet. Additionally, Linux kernel 6.0 adds Sensor Fusion Hub 1.1 support, which improves the capabilities of the sensors of Ryzen-based laptops. Finally, the XP-PEN Deco L drawing tablet is also supported with the new kernel release. Looking at the Intel side, the Linux kernel now adds new hardware support to TCC Cooling Driver: Alder Lake-N and Raptor Lake-P systems.
Additional changes for CPUs
There are some improvements in the process scheduler as well. NUMA balancing for Zen-based AMD systems improved and CPUs will be more efficient while searching for idle CPU cores while they are under heavy load. The patch in the Linux kernel 6.0 scheduler also includes some other balancing features, optimizations, and fixes.
The ACPI (Advanced Configuration and Power Interface) has received some additional improvements such as support for Zhaoxin and Centaur processors on CPUFreq drivers’ boost control UI and fix for the problems with Xeon Sapphire Rapids’ C1 and C1E states. The Chinese CPU architecture, loongArch, now supports PCI and comes with stack unwinder, and stack trace supports in addition to some other changes and bug fixes. Additionally, the kernel takes some initial steps for Compute Express Link (CXL) support; the initial infrastructure for CXL region provisioning lands to the Linux kernel 6.0.
Virtualization improvements
VirtIO, the input/output virtualization framework for Linux has received some tweaks, fixes, and new features for vq resize support with the new vq reset feature. Additionally, KVM receives some polishments with Intel IPI virtualization and AMD x2AVIC supports, which raises the KVM limit to 511 from 255. IPI virtualization can lower the overhead with IPI-sensitive processes and it will be available for Sapphire Rapids series Intel processors. Existing Xeon Ice Lake processors also receive PEBS virtualization support.
RISC-V processor architecture code is receiving some improvements as well. The Svpbmt extension, which delivers the Page-Based Memory Types support is enhanced. The defconfig has received tweaks to run Dockers and Ubuntu Snaps without any problem with the default configuration. There are three new extensions for RISC-V as well: Zicbom, Zihintpause, and Sstc. Finally, it received a system instruction emulation framework, CSR emulation framework, and Svpbmt extension support inside guests too.
GPU driver support
DRM subsystem has received new Intel Alchemist, AMD RDNA3, and AMD Instinct MI300 open-source GPU drivers. AMDKFD compute driver has now P2P DMA with DMA-BUF support, ioctl call support for available VRAM, and HMM profiler support as well. Open-source Nvidia Nouveau driver for Linux kernel 6.0 receives GA103 GPU support, which powers the RTX 3060 Ti graphics cards.
File system changes
The file systems that are available for Linux are also receiving some tweaks as NTFS3 is currently under a refactoring process and is getting some bug fixes. Btrfs, on the other hand, has now Send Stream v2 support that delivers support for reading and writing of compressed data. RAID5 and RAID6 have got some bug fixes and sysfs can display commit stats alongside other minor tweaks and fixes. With some changes, it also triples the performance of asynchronous I/O read operations.
F2FS (Flash Friendly File-System) receives a low-memory mode that can shrink the conserved memory to provide some additional space with some performance cost as well as some improvements for atomic write operations. The NFSD file system also comes with NFSv4 – Courteous Server handling, allowing unresponsive clients’ files to be opened and locked by another client. Additionally, it receives some caching scalability improvements and some bug fixes for some data corruption bugs.
Other changes
On the multimedia side, the H.265/HEVC user space API is now declared “stable” and ready to utilize hardware decoders. PREEMPT_RT, real-time kernel support is landing on kernel 6.0 too. Additionally, the developers are working on the random number generator for Linux, delivering some additional tweaks for bootloaders, hypervisors, and Kexec.
Some of the remaining new features/fixes of Linux kernel 6.0 are listed below:
- UEFI mirrored memory is now supported on AArch64 systems
- ACPI PRM is now supported on AArch64 systems
- New parameter to set a new hostname: “hostname=”
- Run-time verification feature for safety-critical systems
- Some networking optimizations
- WiFi7 preparations
The new Linux kernel is expected to be released on the 2nd of October, 2022.
FAQ
Is it legal to edit the Linux kernel?
Yes, it is legal to edit the Linux kernel since it is under General Public License.
What is the most recent Linux kernel?
Currently, the most recent Linux kernel version is 5.19. The 6.0 version is expected at the beginning of October 2022.
Is the Linux kernel open source?
Yes, the Linux kernel is an open-source project.
Does Linus Torvalds still work on Linux?
Yes, Linus Torvalds still works on developing the Linux kernel.
What is the Linux kernel written in?
Linux kernel code is written in the standard C programming language.
Who developed the Linux kernel?
Linus Torvalds has developed and still developing the Linux kernel.