Re: Linux regressions report for mainline [2021-12-26]

From: Thorsten Leemhuis
Date: Sun Dec 26 2021 - 16:03:09 EST


Two quick notes before I leave the keyboard for today:

On 26.12.21 21:30, Regzbot (on behalf of Thorsten Leemhuis) wrote:
>
> ========================================================
> current cycle (v5.15.. aka v5.16-rc), culprit identified
> ========================================================
> [...]
> fbdev/efifb: Monitors no longer sleep (amdgpu dual monitor setup)
> -----------------------------------------------------------------
> https://linux-regtracking.leemhuis.info/regzbot/regression/8a27c986-4767-bd29-2073-6c4ffed49bba@xxxxxxxxxxx/
> https://lore.kernel.org/linux-fbdev/8a27c986-4767-bd29-2073-6c4ffed49bba@xxxxxxxxxxx/
>
> By Brandon Nielsen, 19 days ago; 4 activities, latest 9 days ago.
> Introduced in 55285e21f045 (v5.16-rc1)
>
> Noteworthy links:
> * https://bugzilla.redhat.com/show_bug.cgi?id=2028613
> * https://bugzilla.kernel.org/show_bug.cgi?id=215203

Note, there was activity in the linked ticket on bugzilla.kernel.org;
regzbot sadly is not able to detect this yet, this and other features to
improve interaction with b.k.o remain on the todo list for now (and
sadly likely will have to remain there for a few weeks, as I have some
other things I need to work on first for the project that made regzbot
possible)

> [...]
> ====================================================
> current cycle (v5.15.. aka v5.16-rc), unkown culprit
> ====================================================
>
>
> mm: reclaim_throttle leads to stall in near-OOM conditions
> ----------------------------------------------------------
> https://linux-regtracking.leemhuis.info/regzbot/regression/20211124011954.7cab9bb4@xxxxxxxxxxxxx/
> https://lore.kernel.org/lkml/20211124011954.7cab9bb4@xxxxxxxxxxxxx/
>
> By Alexey Avramov, 33 days ago; 21 activities, latest 3 days ago.
> Introduced in v5.15..v5.16-rc1
>
> Fix incoming:
> * mm: vmscan: reduce throttling due to a failure to make progress
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?h=master&id=57af06179e3ef2359c3a5e1678edfe0363a0b551
>
>
> mm: LTP/memcg testcase regression induced by 8cd7c588decf..66ce520bb7c2 series
> ------------------------------------------------------------------------------
> https://linux-regtracking.leemhuis.info/regzbot/regression/99e779783d6c7fce96448a3402061b9dc1b3b602.camel@xxxxxx/
> https://lore.kernel.org/lkml/99e779783d6c7fce96448a3402061b9dc1b3b602.camel@xxxxxx/
>
> By Mike Galbraith, 35 days ago; 33 activities, latest 3 days ago.
> Introduced in 8cd7c588decf..66ce520bb7c2 (v5.15..v5.16-rc1)
>
> Fix incoming:
> * mm: vmscan: reduce throttling due to a failure to make progress
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?h=master&id=57af06179e3ef2359c3a5e1678edfe0363a0b551

I wonder why the fix for those two was not among the patches from akpm
merged yesterday; guess will investigate tomorrow.

Ciao, Thorsten