Linux Kernel Daily: Late-Cycle Fixes for Scheduling and Sysctl
This cycle's late fixes cluster around correctness bugs in the sched-ext scheduler framework and a resurfaced range-check regression in sysctl's millisecond-to-jiffies conversion, both patterns pointing to edge cases missed in earlier refactors.
Duration: PT2M30S
Episode overview
This episode is a short developer briefing from Linux Kernel Daily.
It explains recent repository work in plain language.
- Show: Linux Kernel Daily
- Published: 2026-09-16T06:02:41Z
- Audio duration: PT2M30S
Transcript excerpt
This excerpt keeps the crawler page concise. Listen to the episode or use the RSS feed for the full update.
Good day. It's September 16th, 2026, and this is Linux Kernel Daily.
Today's activity is all fixes, no new features, and the pattern is clear: two subsystems are cleaning up edge cases that slipped through earlier work.
The bigger batch is sched-ext, pulled by Linus in commit 9b87fdc from Tejun Heo's tree. Several of these are genuine correctness hazards. Commit 9a0b159 fixes a case in the example scheduler, scx qmap, where a CPU claims an idle compute ID but the task never arrives, leaving that ID stuck marked busy indefinitely.…
The second theme is sysctl, and it's a case of a fix undoing a previous fix's damage. Two prior refactors — replacing custom conversion macros and the do_proc functions — accidentally dropped range checks on millisecond-to-jiffies conversions. Kuniyuki Iwashima's commits 318012c and 8243187 restore those checks, and…
Worth a quick mention: a cgroup fix in 6fb20c0 stops the task iterator from resurrecting a dying task with a zero refcount when reading cgroup dot procs — another use-after-free class bug.
What to remember: when refactoring conversion or validation logic, audit for silently dropped bounds checks — that's exactly how the sysctl bug got…
Nearby episodes from Linux Kernel Daily
- A Week of Late-Cycle Hardening
- Weekly Recap - Late-Cycle Fixes Converge Across Memory, Tracing, and Crypto
- The Great Regression Cleanup
- Late-Cycle Fixes Converge on Crypto, Filesystems, and Build Tooling
- The RC3 Bounds-Checking Sweep
- The RC3 Fix Wave
- Locking Bugs Under the Microscope
- AMD Fixes Converge Ahead of 7.3