Linux Kernel 6.4 Officially Released, This Is What’s New

This release introduces Intel LAM support, more Rust language code, new RISC-V features, and more.
Linux Kernel 6.4

Linus Torvalds released today Linux 6.4 as the latest and greatest kernel series for Linux-based operating systems, a major update that brings better hardware support and new features.

Highlights of Linux kernel 6.4 include Intel LAM (Liniar Address Masking) support, user trace events, the ability for the machine keyring used for Machine Owner Keys (MOK) to store only CA-enforced keys, LoongArch support for the nolibc library, support for zoned block devices for the F2FS file system, as well as support for the Svnapot extension and hibernation support for the RISC-V architecture.

The io_uring subsystem was improved to be able to perform multiple direct-I/O writes at the same time to a file (currently only supported on EXT4 and XFS filesystems), the SCTP (Stream Control Transmission Protocol) protocol gained support for the Fair and Weighted Fair Queuing (WFQ) schedulers, and a new netlink-based API was implemented to call out the user space for helper functions.

The s390 (IBM System z) architecture received support for the STACKLEAK security feature, the NFS server implementation now supports the RFC 9289 specification, and the perf tool gained many changes like a new reference-count checking infrastructure, updated default map size to 16384, Python support in ‘perf script’ when the libtraceevent library is not linked, better lock-contention reporting, and the ability to use BPF to filter samples.

Rust language support gained a few additions as well, including the ‘ARef’ type used in wrappers for C types that have their own ref counting functions, several new locking primitives, the pin-init API core for facilitating safe pinned initialization of struct, ‘LockedBy’ for protecting data with a lock, a UAPI crate for mirroring the bindings crate, and other functions.

Other than that, Linux kernel 6.4 adds a new Qualcomm QAIC DRM accelerated driver for their Cloud AI, KVM support for virtual NMIs on x86 AMD, fbdev emulation for GEM DMA drivers, Qualcomm Inline Crypto Engine support, support for new MMIO based models (T2 Macs), Intel Sierra Forest EDAC support, better BIG TCP performance, and a new BPF netfilter program type.

Linux kernel 6.4 also looks to bring various thermal improvements in the Mediatek driver, enhancements of very old PCI sound cards, sound support for NVIDIA systems with MAX9809x and RT5631 codecs, generic support for all Kye tablets, support for the Logitech G935 wireless 7.1 surround sound gaming headphones, and PPIN support for Intel’s 5th Gen Xeon “Emerald Rapids” server processors.

New drivers are also present in Linux 6.4 for the StarFive JH71x0 temperature sensor and the StarFive JH7110 RISC-V SoC, Acbel FSB032 power supply, Aquacomputer Aquastream XT pump, and the ROG STRIX Z390-F GAMING motherboard.

Moreover, there’s rumble support for the latest Xbox controllers, Apple M2 CPU PMU support, Wi-Fi 7 (EHT) mesh support, improved support for Qualcomm Snapdragon platforms, a new driver for Novatek touch controllers, support for the Lenovo Yoga Book X90F 2-in-1 tablet, Hyper-V VTL mode support, and Wi-Fi support for Apple M1 Pro/Max devices.

The AMDGPU graphics driver got initial NBIO7.9, GC 9.4.3, GFXHUB 1.2, MMHUB 1.8 support, initial DC FAM infrastructure, sysfs nodes for secondary VCN clocks, as well as capped/uncapped workload handling for supported APUs. Moreover, the Mediatek DRM driver received 10-bit overlay support, the Rockchip DRM driver got 4K support, and Collabora’s Panfrost driver now supports Mali MT81xx devices.

Linux kernel 6.4 is available for download from Linus Torvalds’ git tree here or from the website if you know how to compile it yourself on your GNU/Linux distribution. Otherwise, you must wait until Linux kernel 6.4 lands in your distro’s stable software repositories.

Last updated 10 months ago

Buy Me a Coffee at