Re: stable: commit "cpuidle: menu: Avoid discarding useful information" causes regressions
From: Greg Kroah-Hartman
Date: Tue Oct 14 2025 - 03:47:27 EST
On Tue, Oct 14, 2025 at 04:43:43PM +0900, Sergey Senozhatsky wrote:
> Hello,
>
> We are observing performance regressions (cpu usage, power
> consumption, dropped frames in video playback test, etc.)
> after updating to recent stable kernels. We tracked it down
> to commit 3cd2aa93674e in linux-6.1.y and commit 3cd2aa93674
> in linux-6.6.y ("cpuidle: menu: Avoid discarding useful information",
> upstream commit 85975daeaa4).
>
> Upstream fixup fa3fa55de0d ("cpuidle: governors: menu: Avoid using
> invalid recent intervals data") doesn't address the problems we are
> observing. Revert seems to be bringing performance metrics back to
> pre-regression levels.
>
For some reason that commit was not added to the 6.1 releases, sorry
about that. Can you submit a working/tested backport so we can queue it
up after the next round of releases in a few days?
thanks,
greg k-h