I was a little overzealous in removing the rcu_read_lock() call from blkcg_bio_issue_check() and it broke blk-throttle. Put it back. Fixes: e35403a034bf ("blkcg: associate blkg when associating a device") Signed-off-by: Dennis Zhou <dennis@xxxxxxxxxx> --- include/linux/blk-cgroup.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index 752de1becb5c..bf13ecb0fe4f 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -764,6 +764,8 @@ static inline bool blkcg_bio_issue_check(struct request_queue *q, struct blkcg_gq *blkg; bool throtl = false; + rcu_read_lock(); + if (!bio->bi_blkg) { char b[BDEVNAME_SIZE]; @@ -791,6 +793,7 @@ static inline bool blkcg_bio_issue_check(struct request_queue *q, blkcg_bio_issue_init(bio); + rcu_read_unlock(); return !throtl; } -- 2.17.1