tree 5ae81744cf93a34777e836a7fc4680b25c162002
parent d29bd41428cfff9b582c248db14a47e2be8457a8
author Tejun Heo <tj@kernel.org> 1634253622 -1000
committer Jens Axboe <axboe@kernel.dk> 1634488810 -0600

blk-cgroup: blk_cgroup_bio_start() should use irq-safe operations on blkg->iostat_cpu

c3df5fb57fe8 ("cgroup: rstat: fix A-A deadlock on 32bit around
u64_stats_sync") made u64_stats updates irq-safe to avoid A-A deadlocks.
Unfortunately, the conversion missed one in blk_cgroup_bio_start(). Fix it.

Fixes: 2d146aa3aa84 ("mm: memcontrol: switch to rstat")
Cc: stable@vger.kernel.org # v5.13+
Reported-by: syzbot+9738c8815b375ce482a1@syzkaller.appspotmail.com
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/YWi7NrQdVlxD6J9W@slm.duckdns.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>