+ mm-vmscan-restore-incremental-cgroup-iteration-fix.patch added to mm-unstable branch

+ mm-vmscan-restore-incremental-cgroup-iteration-fix.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm: vmscan: reset sc->priority on retry
has been added to the -mm mm-unstable branch.  Its filename is
     mm-vmscan-restore-incremental-cgroup-iteration-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmscan-restore-incremental-cgroup-iteration-fix.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Shakeel Butt <shakeel.butt@linux.dev>
Subject: mm: vmscan: reset sc->priority on retry
Date: Wed, 29 May 2024 08:49:11 -0700

The commit 6be5e186fd65 ("mm: vmscan: restore incremental cgroup
iteration") added a retry reclaim heuristic to iterate all the cgroups
before returning an unsuccessful reclaim but missed to reset the
sc->priority.  Let's fix it.

Link: https://lkml.kernel.org/r/20240529154911.3008025-1-shakeel.butt@linux.dev
Fixes: 6be5e186fd65 ("mm: vmscan: restore incremental cgroup iteration")
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Reported-by: syzbot+17416257cb95200cba44@syzkaller.appspotmail.com
Tested-by: syzbot+17416257cb95200cba44@syzkaller.appspotmail.com
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmscan.c |    1 +
 1 file changed, 1 insertion(+)

--- a/mm/vmscan.c~mm-vmscan-restore-incremental-cgroup-iteration-fix
+++ a/mm/vmscan.c
@@ -6304,6 +6304,7 @@ retry:
 	 * meaningful forward progress. Avoid false OOMs in this case.
 	 */
 	if (!sc->memcg_full_walk) {
+		sc->priority = initial_priority;
 		sc->memcg_full_walk = 1;
 		goto retry;
 	}
_

Patches currently in -mm which might be from shakeel.butt@linux.dev are

mm-vmscan-restore-incremental-cgroup-iteration-fix.patch