mm: vmscan: reset sc->priority on retry

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>

diff --git a/mm/vmscan.c b/mm/vmscan.c
index a72864b4b620ca7a17848971b9de9cf3deff4262..d1a87ceef0dce7551c6f18c366fd49ffd07763ea 100644 (file)
--- a/mm/vmscan.c
+++ b/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;
        }