diff options
| author | Yu Zhao <yuzhao@google.com> | 2023-06-19 13:38:21 -0600 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-06-23 16:10:12 -0700 |
| commit | 814bc1de03ea4361101408e63a68e4b82aef22cb (patch) | |
| tree | b98bd538c2a32c7de46bf744c2ef7a07e453bae9 /mm/vmscan.c | |
| parent | 0518dbe97fe629fea255318841cf3ef1b4532d66 (diff) | |
mm/mglru: make memcg_lru->lock irq safe
lru_gen_rotate_memcg() can happen in softirq if memory.soft_limit_in_bytes
is set. This requires memcg_lru->lock to be irq safe. Lockdep warns on
this.
This problem only affects memcg v1.
Link: https://lkml.kernel.org/r/20230619193821.2710944-1-yuzhao@google.com
Fixes: e4dde56cd208 ("mm: multi-gen LRU: per-node lru_gen_folio lists")
Signed-off-by: Yu Zhao <yuzhao@google.com>
Reported-by: syzbot+87c490fd2be656269b6a@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=87c490fd2be656269b6a
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/vmscan.c')
| -rw-r--r-- | mm/vmscan.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index 5bf98d0a22c9..6114a1fc6c68 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -4728,10 +4728,11 @@ static void lru_gen_rotate_memcg(struct lruvec *lruvec, int op) { int seg; int old, new; + unsigned long flags; int bin = get_random_u32_below(MEMCG_NR_BINS); struct pglist_data *pgdat = lruvec_pgdat(lruvec); - spin_lock(&pgdat->memcg_lru.lock); + spin_lock_irqsave(&pgdat->memcg_lru.lock, flags); VM_WARN_ON_ONCE(hlist_nulls_unhashed(&lruvec->lrugen.list)); @@ -4766,7 +4767,7 @@ static void lru_gen_rotate_memcg(struct lruvec *lruvec, int op) if (!pgdat->memcg_lru.nr_memcgs[old] && old == get_memcg_gen(pgdat->memcg_lru.seq)) WRITE_ONCE(pgdat->memcg_lru.seq, pgdat->memcg_lru.seq + 1); - spin_unlock(&pgdat->memcg_lru.lock); + spin_unlock_irqrestore(&pgdat->memcg_lru.lock, flags); } void lru_gen_online_memcg(struct mem_cgroup *memcg) @@ -4779,7 +4780,7 @@ void lru_gen_online_memcg(struct mem_cgroup *memcg) struct pglist_data *pgdat = NODE_DATA(nid); struct lruvec *lruvec = get_lruvec(memcg, nid); - spin_lock(&pgdat->memcg_lru.lock); + spin_lock_irq(&pgdat->memcg_lru.lock); VM_WARN_ON_ONCE(!hlist_nulls_unhashed(&lruvec->lrugen.list)); @@ -4790,7 +4791,7 @@ void lru_gen_online_memcg(struct mem_cgroup *memcg) lruvec->lrugen.gen = gen; - spin_unlock(&pgdat->memcg_lru.lock); + spin_unlock_irq(&pgdat->memcg_lru.lock); } } @@ -4814,7 +4815,7 @@ void lru_gen_release_memcg(struct mem_cgroup *memcg) struct pglist_data *pgdat = NODE_DATA(nid); struct lruvec *lruvec = get_lruvec(memcg, nid); - spin_lock(&pgdat->memcg_lru.lock); + spin_lock_irq(&pgdat->memcg_lru.lock); VM_WARN_ON_ONCE(hlist_nulls_unhashed(&lruvec->lrugen.list)); @@ -4826,7 +4827,7 @@ void lru_gen_release_memcg(struct mem_cgroup *memcg) if (!pgdat->memcg_lru.nr_memcgs[gen] && gen == get_memcg_gen(pgdat->memcg_lru.seq)) WRITE_ONCE(pgdat->memcg_lru.seq, pgdat->memcg_lru.seq + 1); - spin_unlock(&pgdat->memcg_lru.lock); + spin_unlock_irq(&pgdat->memcg_lru.lock); } } |