Linus Torvalds releases Linux Kernel 5.19 RC1 for testing, bringing a vast amount of changes.
Following the Linux Kernel 5.18 release last month, Linus Torvalds announced the first release candidate availability of Linux Kernel 5.19. With this announcement, the official merge window of Linux Kernel 5.19 closes, meaning no new features are to be accepted unless it’s critical.
A brief look at the new items in Linux Kernel 5.19 shows regular updates across CPU, GPU, networking, storage and core modules. In addition, the code cleanups, removal of obsolete hardware and continuous support for future chipsets are the highlight of this release.
Without further introduction, let’s take a look at the new features.
Linux Kernel 5.19 – New Features (RC1)
First and foremost, Linux Kernel 5.19 begins initial support for the LoongArch CPU family. It is developed by the Chinese company Loongson. LoongArch CPUs are the general general-purpose, MIPS architecture-compatible microprocessors. Although the support is now available, you can not boot Linux in these CPUs because some code is still under review. And hopefully, they will be already in the 5.20 version.
The new Intel IFS driver lands in this version which helps to detect hardware issues before deployment and after. It will help detect CPU faults at the circuit level at an early stage.
The power management and thermal work have continued for the last couple of Kernel releases for Intel CPUs. And this release also is no exception. Firstly, the Intel Run-Time Average Power Limiting (RAPL) support was added for Raptor and Alder Lake family. Second, the P-state driver is improved to handle frequency variance and CPU based scaling support is added to the passive devfreq.
While the thermal and power dominated Intel CPUs, AMD sees more performance updates in its own CPU families. Firstly, more updates were introduced in the Instruction-Based Sampling (IBS) module for AMD Zen 4 CPUs are planned for the end of this year. Moreover, PerfMonV2 is introduced in this release giving more performance monitoring capabilities.
Furthermore, the a.out support is removed in this release. Also, the Renesas H8/300 CPU architecture support is removed as its obsolete by now.
Major ARM update
Finally, the mainline Linux Kernel can support multiple ARM platforms with this release. This is a big step in this version, which is heard in Linus’s opening note on this Rc1 release. This is a long process that started with Linux 3.7 and spanned more than a decade of work and patches.
Graphics and Storage Updates
The storage subsystem sees performance improvements across popular file systems. The significant changes include Apple M1 NVMe controller support and better support for the XFS file system. In addition, enhancements arrive for Btrfs, F2FS and exFAT file systems.
One of the exciting metrics in terms of LOC is Linux Kernel 5.19 adds around half-million lines of code for the Graphics driver alone. It includes graphics updates across AMD RDNA, CDNA, Intel’s Raptor Lake, Intel’s DG2/Alchemist and more.
Important Networking Changes
Looking at the massive growth in the data transmission, the support for Big TCP lands which helps the data centre traffic at a range of 400GBit. It also aims to give lower latency in high-performance networking environments.
The Multi-Path TCP (MPTCP) continues its improvements. In addition to that, Qualcomm ath11k WiFi driver adds wake-on-lan support in this version. Also, support is added for Realtek 8852ce chipset, MediaTek T700 modems and Rensas RZ/V2M
Other Notable Features
Firstly, the famous random number generator in Kernel continues its improvements in this release.
Second, the famous and emerging Framework Modular Laptop gets this release Chrome OS EC Driver support. The Framework laptop now can take advantage of ChromeOS’s embedded controller as a non-Chromebook device.
Moreover, more updates arrive at Wacom tabs and other related devices. It includes improved support for Lenovo Thinkpad TrackPoint II, Google Whiskers Touchpad, Lenovo X12 TrackPoint, etc.
Linux Kernel 5.19 Download
If you want to test and try this release candidate, download the release tarball here. Or refer below for a direct link to tar and diffs.
There will be multiple kernel iterations until the final release, expected around July 2022.
Via Kernel mailing list.