From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dennis Zhou Subject: [PATCH] blkcg: put back rcu lock in blkcg_bio_issue_check() Date: Thu, 6 Dec 2018 12:49:38 -0500 Message-ID: <20181206174938.2326-1-dennis@kernel.org> Return-path: Sender: linux-kernel-owner@vger.kernel.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Jens Axboe , Tejun Heo , Johannes Weiner , Josef Bacik Cc: kernel-team@fb.com, linux-block@vger.kernel.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Dennis Zhou 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 --- 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