We already have here a new version of the kernel of the operating system(s) that the editors and readers of blogs like this one like the most. On this occasion, after 5.18 it was the turn of linux 5.19, which Linus Torvalds has just announced its release. When I say that "it was his turn", I mean that it was the logical thing to do, and it has been that way since its development began, but there was some more doubt about whether the next one would be Linux 5.20 or already Linux 6.0. But this article is about the latest stable version, whose release is now official.
Linux 5.19 is a major release. Already in the fusion window it was verified that there were going to be many changes, although the amount of them has not made the kernel grow in size. Below is a list with the most outstanding news, pick up from Phoronix, a specialized medium that closely follows the development of Linux, among other things such as its famous analyzes and comparisons of all types of hardware.
Linux 5.19 Highlights
- Processors and platforms:
- Intel In-Field Scan (IFS) has been merged to facilitate CPU silicon testing prior to data center deployments or silicon testing over time to help detect any undiscovered hardware issues. ECC checks or other existing tests.
- LoongArch was merged as a new CPU port for the Linux kernel. However, as noted, there is no support for booting any LoongArch systems yet due to some drivers not being ready for mainlining yet.
- Support for the PolarBerry RISC-V FPGA board that makes use of the PolarFire SoC.
- Support for running 32-bit (RV32) binaries on 64-bit RISC-V (RV64).
- Completing the 12-year cross-platform Arm effort with finally converting the old ARMv4T/ARMv5 code for cross-platform kernel builds. Arm cross-platform support for older Intel XScale/PXA hardware has also been completed.
- Added HPE GXP SoC that will be used for Baseboard Management Controller (BMC) functions in upcoming HPE servers.
- Support for ARMv9 Scalable Matrix Extension. Scalable Matrix Extension (SME) is based on SVE/SVE2.
- The refinement changes are significant on the AMD side, with extensions to Zen 4 IBS, AMD PerfMonV2, and finally AMD Zen 3 Branch Sampling (BRS).
- Removal of the old Renesas H8/300 CPU architecture. This architecture is old and hasn't been maintained in the kernel for years, having already been removed from the mainline once.
- Removal of deprecated x86 support a.out.
- Many thermal and power management updates from Intel, including a fix for hot Linux laptops draining the battery while trying to sleep.
- Easier cleanup of CPUID features.
- Late loading of microcode for x86/x86_64 disabled by default and will corrupt the kernel. Users are advised to load the CPU microcode early.
- Virtualization:
- AMD SEV-SNP is finally mainlined for the Secure Encrypted Virtualization (SEV) update introduced with AMD EPYC 7003 "Milan" processors.
- Intel Trust Domain Extensions (TDX) has been merged with early code ready.
- Support for XSAVEC when running as a VM guest.
- Microsoft has slashed Hyper-V guest boot times for large Azure virtual machines with many GPUs.
- Support for Linux EFO to access VM secrets for Confidential Computing (CoCo) hypervisors such as with AMD SEV.
- KVM and Xen updates.
- A new m68k virtual machine target for virtualization use that is based on Google's Goldfish and is much more capable than existing Motorola 68000 emulation options.
- Graphics and displays:
- Nearly half a million lines of new code.
- A lot of work is being done to enable IP blocks for AMD RDNA3 graphics to be released later this year alongside the next generation CDNA Instinct accelerators.
- Intel DG2/Alchemist PCI IDs for motherboard down designs.
- Support for Intel Raptor Lake P graphics, from existing code paths.
- The compute engine ABI is now exposed for DG2/Alchemist hardware.
- A power quirk for DG2/Alchemist GPUs to ensure PCIe Active State Power Management (ASPM) is successfully enabled.
- ASpeed AST driver support for DisplayPort.
- Rockchip VOP2 compatibility.
- Support for a new basic variant of RDNA2 "Beige Goby".
- MediaTek Vcodec support for VP8 and VP9 stateless codecs.
- File systems and storage:
- Numerous notable improvements to the Btrfs filesystem, from subpage support for any PAGE_SIZE greater than 4K to subpage support for Btrfs native RAID 5/6 modes and other additions.
- Support for Apple's NVMe M1 controller.
- Lots of new code for the XFS file system.
- Creation of FAT16/FAT32 files/time of birth information via statx system call.
- NTFS3 kernel driver fixes have been merged to finally address some maintenance issues with this NTFS kernel driver contributed to the kernel last year by Paragon Software.
- Various improvements to F2FS and routine updates to EROFS and EXT4.
- Support for NFSv3 Courteous Server.
- eMMC support for using TRIM to zero sectors.
- Support for IDMAPPED layers with OverlayFS.
- A great performance fix for exFAT.
- Lots of improvements to IO_uring.
- Other hardware:
- Endless work on the Synopsys DWC3 USB3 driver.
- Merged Apple eFuses driver to read these programmed eFuses in Apple M1 SoCs to store calibration data.
- Work has continued on the Intel Havana Labs AI driver.
- Support for initiating firmware updates via sysfs for Intel FPGA PCIe card use and other possible use cases.
- Support for reporting the physical location of a connected device when exposed as via ACPI. This can help notice where a connected component is relative to the server/system in cases of multiple ports/locations etc.
- The Raspberry Pi Sense HAT joystick driver was merged.
- Chrome OS EC driver support for the Laptop Framework.
- Continued enablement of Compute Express Link (CXL) support for next generation servers.
- Better support for the Lenovo ThinkPad Trackpoint II keyboard.
- Proper handling of Keychron C-Series/K-Series keyboards.
- Wacom driver improvements and other HID work.
- Intel's AVS audio driver started landing as a rewrite of the old Skylake/Kabylake/Apollo Lake/Amber Lake-era audio driver code.
- Continuation of hardware monitoring improvements of ASUS motherboard additions to Aquacomputer devices.
- Security:
- Clang RandStruct support for randomizing structure layout and similar to existing GCC support.
- Continuation of the modernization work of the RNG code for the generation of random numbers.
- Intel SGX enclaves were prone to failing under high memory pressure, but that problem for Software Guard Extensions on Linux is now resolved.
- Making life miserable for application developers who misbehave in using split-lock.
- Others:
- Many significant networking improvements, from Big TCP to pureLiFi LED lighting for wireless communication, and many other enhancements.
- A new option to easily configure an x86_64 debug kernel.
- Printk will now download messages to KThreads by console.
- Many improvements in memory management.
- A new merged subsystem is the Hardware Timestamping Engine (HTE) to coordinate between time providers and consumers like GPIOs and IRQs. The initial HTE provider with Linux 5.19 is for the NVIDIA Tegra Xavier SoC only. Although Linus Torvalds doesn't like the HTE name and it could still be changed this cycle or the next.
- Spring cleaning to the staging area, including the promotion of the WFX WiFi driver outside of the staging area.
- Zstd compressed firmware support as an alternative to the existing XZ compressed firmware support to save disk space by compressing the many firmware binaries present on modern Linux systems.
Linux 5.19 it was announced a few moments ago, and your code is now available, and will be soon, at The Kernel Archive. Ubuntu users who want to install it right away will have to do it on their own or with tools like Umki, or wait for the October launch and make the leap to a bigger one.