Linux Kernel 6.12.69 Released – What’s New and Why It Matters
The latest kernel, 6.12.69, arrives with a handful of solid fixes that quietly make the system more stable, especially for users running on Hyper‑V or who have seen CPU spikes from writeback. Below is a quick rundown of what you should know before you jump into the upgrade.
Key Bug Fixes – The “Real‑World” Impact
Hyper‑V RDMA Master Device Handling A bug in RDMA’s master‑device tracking caused the device pointer to become stale after an unbind/rebind cycle, leading to subtle crashes when the driver tried to access a freed netdev. If you’ve ever hit a “NULL pointer dereference” while moving virtual machines around, this patch is exactly what stops that from happening again.
100 % CPU Spikes from Writeback
The kernel used to schedule dirty‑time writeback with a zero delay whenever vm.dirtytime_expire_seconds was set to zero. That meant the delayed work ran in an endless loop, hogging a kworker thread and driving your CPU up to full throttle. After this fix, you’ll notice that background flushes no longer spin the CPU when you tweak those sysctl knobs.BPF Test Header Cleanup
One of the self‑test harnesses was pulling stdlib.h even though it didn’t use any of its symbols. It sounds trivial, but removing the header eliminates an unnecessary dependency and keeps the test suite leaner—good news for people trying to build bpf programs on minimal systems.Pin‑ctrl Driver Improvements
The LPASS LPI driver now implements .get_direction() so that GPIO state queries work correctly. If you’re troubleshooting audio or I/O pins on a Qualcomm board, you’ll see fewer “direction unknown” warnings in dmesg.
Performance Tweaks That Make a Difference
AMD GPU Queue Reset Optimisation AMD’s gfx11 driver no longer re‑initialises queues after a reset, avoiding redundant MMIO writes. For users who run heavy OpenGL workloads on an APU, this translates to slightly lower latency during context switches.
GSO Fragment List Fix for XLAT
When forwarding GRO packets that contain a fragment list, the kernel now correctly honours the SKB_GSO_DODGY flag. On Wi‑Fi routers that use network address translation, this reduces packet loss and improves throughput.
Security & Reliability Enhancements
Perf Crash Prevention The new is_user_task() helper stops perf from crashing when it tries to read user memory during a kernel thread’s exit. If you run custom profiling tools on production servers, the risk of accidental panics is lowered.
NVMe Target Race Fix
NVMe‑target now performs bio cleanup before re‑submitting requests, preventing a race that could lead to NULL pointer dereference in blk_cgroup_bio_start. For storage‑heavy workloads this means more reliable I/O paths.
Other Kernel Versions Updated Today
Alongside 6.12.69, the maintainers have also released 5.10.249, 5.15.199, 6.1.162, and 6.6.123. If you’re on a distribution that still runs one of those LTS branches, you can pick the matching patch set for your release series.
What to Watch Out For
- If you use custom modules that depend on the old RDMA behaviour, double‑check the module logs after upgrading.
- The writeback change means vm.dirtytime_expire_seconds will no longer cause CPU spikes if left at zero; however, it also removes a “quick fix” that some users relied on to force aggressive flushing. Adjust your sysctl settings accordingly.
That’s the low‑down for kernel 6.12.69. Patch up and enjoy a more predictable system—no more mysterious crashes when you move VMs, no more CPU‑hogging background tasks.
Linux kernel 6.12.69 released
Linux kernel version 6.12.69 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.12.69.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v6.x/patch-6.12.69.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.12.69.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v6.12.69/v6.12.68
Linux kernel 6.6.123 released
Linux kernel version 6.6.123 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.6.123.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v6.x/patch-6.6.123.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.6.123.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v6.6.123/v6.6.122
Linux kernel 6.1.162 released
Linux kernel version 6.1.162 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.1.162.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v6.x/patch-6.1.162.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.1.162.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v6.1.162/v6.1.161
Linux kernel 5.15.199 released
Linux kernel version 5.15.199 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.15.199.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v5.x/patch-5.15.199.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.15.199.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v5.15.199/v5.15.198
Linux kernel 5.10.249 released
Linux kernel version 5.10.249 is now available:
Full source: https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.249.tar.xz
Patch: https://cdn.kernel.org/pub/linux/kernel/v5.x/patch-5.10.249.xz
PGP Signature: https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.249.tar.sign
You can view the summary of the changes at the following URL:
https://git.kernel.org/stable/ds/v5.10.249/v5.10.248
