Linus Torvalds has announced the fourth release candidate (RC4) of Linux Kernel 6.13 on December 22, 2024. The Kernel 6.13-rc4 brings a collection of fixes and improvements across various subsystems.
In the release announcement, Torvalds mentioned that this rc4 is slightly smaller than typical rc4 updates, which is a good sign for the stability of the upcoming release. He also expressed hope that rc5 will be even tinier, as developers are likely to be taking a break over the Christmas holidays.
[…]
So this definitely is looking a bit smaller than most rc4s, and I
expect (and hope) that rc5 will be absolutely tiny because you should
all already be relaxing over the xmas holidays.
[…]
He encourages everyone to keep testing, especially those who are still working during the festive season.
Table of Contents
What’s New in Linux Kernel 6.13 RC4?
The Linux kernel 6.13-rc4 comes with numerous bug fixes from various contributors. These fixes address issues across diverse kernel components, including drivers, memory management, networking, and the file system.
The fixes range from minor compiler warnings to critical error handling improvements. Here’s a brief overview of some of the key fixes and improvements:
1. AMD GPU Fixes
Several fixes have been made to the AMD GPU drivers, particularly in the drm/amdgpu subsystem. These include:
- Fixes for IP version checks in various AMD GPU components like nbio7.7, nbio7.11, mmhub4.1, gfx12, and smu14.0.2.
- Improvements in error handling and memory management.
2. BPF and Networking Fixes
The BPF (Berkeley Packet Filter) subsystem has seen several updates, including:
- Fixes for bpf_skb_change_tail() and bpf_tcp_ingress().
- New selftests to ensure the stability and correctness of BPF functionality.
Networking-related fixes include:
- Improvements in netdevsim to prevent bad user input and handle health break write operations correctly.
- Fixes in team driver to ensure proper feature exposure even when no ports are present.
3. Memory Management and VM Fixes
Memory management has received attention with fixes like:
- Preventing potential integer overflows in chelsio/chtls.
- Ensuring proper handling of PFN (Page Frame Number) in split_large_buddy().
- Fixes for zram to prevent uninitialized backing devices and zero-sized block devices.
4. Thermal and Power Management
Thermal subsystem fixes include:
- Correcting boundaries and detection routines in thermal/thresholds.
- Ensuring proper handling of cpufreq/amd-pstate to detect preferred core support before driver registration.
5. Device Tree and ACPI Fixes
The Device Tree and ACPI subsystems have also seen their fair share of fixes:
- Adding empty dma-ranges address translation tests.
- Fixing ACPI EC (Embedded Controller) support on LoongArch.
6. USB and Serial Fixes
USB and serial drivers have received several updates, including:
- Adding support for new devices like TCL IK512 MBIM & ECM, MediaTek T7XX, and MeiG Smart SLM770A.
- Fixes for option driver to handle new compositions and prevent memory leaks.
7. Filesystem and Storage Fixes
Filesystem-related fixes include:
- Preventing memory leaks in ceph and nilfs2.
- Ensuring proper handling of btrfs in the completion handler and splitting bios to the filesystem sector size boundary.
8. Miscellaneous Fixes
Other notable fixes include:
- Improvements in io_uring to prevent memory leaks and ensure proper handling of registered ring files.
- Fixes in xen/netfront to prevent crashes when removing devices.
- Updates in selftests to ensure better coverage and correctness.
Test Linux Kernel 6.13-rc4
Every new release brings improvements in performance, security, and compatibility with newer hardware. By testing the release candidates, users can help identify and fix bugs before the final release, ensuring a more stable and reliable experience for everyone.
If you’re a developer, system administrator, or just someone who loves tinkering with Linux, please download and test Linux Kernel 6.13-rc4.
To try out the latest release candidate, you can download the source code from the official Linux Kernel Archive or from the Linus Torvalds's git tree.
Happy testing, and Happy Holidays!
