Update of blkg_stat and blkg_rwstat may happen in bh context. While u64_stats_fetch_retry is only preempt_disable on 32bit UP system. This is not enough to avoid preemption by bh and may read strange 64 bit value.
Update of blkg_stat and blkg_rwstat may happen in bh context.
While u64_stats_fetch_retry is only preempt_disable on 32bit
UP system. This is not enough to avoid preemption by bh and
may read strange 64 bit value.

Signed-off-by: Hong Zhiguo <b3ee58addc3b7ac6788553729231dbdcae1c7e7f@tencent.com>
Acked-by: Tejun Heo <546b05909706652891a87f7bfe385ae147f61f91@kernel.org>
Cc: 4fbacc2fa0ffdbb11bf1ad6925b886ebd08dd15f@kernel.org
Signed-off-by: Jens Axboe <cd8c6775e60d6f67a6984377324e5290df3d5358@kernel.dk>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs