+ workingset-refactor-lru-refault-to-expose-refault-recency-check-fix.patch added to mm-unstable branch

+ workingset-refactor-lru-refault-to-expose-refault-recency-check-fix.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: workingset: add missing rcu_read_unlock() in lru_gen_refault()
has been added to the -mm mm-unstable branch.  Its filename is
     workingset-refactor-lru-refault-to-expose-refault-recency-check-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/workingset-refactor-lru-refault-to-expose-refault-recency-check-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: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Subject: workingset: add missing rcu_read_unlock() in lru_gen_refault()
Date: Wed, 10 May 2023 07:22:55 +0900

syzbot is reporting sleep in RCU context, for commit d66c718d28ac
("workingset: refactor LRU refault to expose refault recency check")
missed rcu_read_unlock().

Link: https://lkml.kernel.org/r/610781bc-cf11-fc89-a46f-87cb8235d439@I-love.SAKURA.ne.jp
Reported-by: syzbot <syzbot+3c6cac1550288f8e7060@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=3c6cac1550288f8e7060
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: d66c718d28ac ("workingset: refactor LRU refault to expose refault recency check")
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Nhat Pham <nphamcs@gmail.com>
Cc: Brian Foster <bfoster@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/workingset.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/workingset.c~workingset-refactor-lru-refault-to-expose-refault-recency-check-fix
+++ a/mm/workingset.c
@@ -303,7 +303,7 @@ static void lru_gen_refault(struct folio
 		goto unlock;
 
 	if (pgdat != folio_pgdat(folio))
-		return;
+		goto unlock;
 
 	lruvec = mem_cgroup_lruvec(memcg, pgdat);
 	lrugen = &lruvec->lrugen;
_

Patches currently in -mm which might be from penguin-kernel@I-love.SAKURA.ne.jp are

workingset-refactor-lru-refault-to-expose-refault-recency-check-fix.patch
mm-page_alloc-dont-wake-up-kswapd-from-rmqueue-unless-__gfp_kswapd_reclaim-is-specified.patch