From c164c7bc9775be7bcc68754bb3431fce5823822e Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Thu, 17 Aug 2023 22:17:51 +0800 Subject: blk-cgroup: hold queue_lock when removing blkg->q_node When blkg is removed from q->blkg_list from blkg_free_workfn(), queue_lock has to be held, otherwise, all kinds of bugs(list corruption, hard lockup, ..) can be triggered from blkg_destroy_all(). Fixes: f1c006f1c685 ("blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy()") Cc: Yu Kuai Cc: xiaoli feng Cc: Chunyu Hu Cc: Mike Snitzer Cc: Tejun Heo Signed-off-by: Ming Lei Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20230817141751.1128970-1-ming.lei@redhat.com Signed-off-by: Jens Axboe --- block/blk-cgroup.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index fc49be622e05..9faafcd10e17 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -136,7 +136,9 @@ static void blkg_free_workfn(struct work_struct *work) blkcg_policy[i]->pd_free_fn(blkg->pd[i]); if (blkg->parent) blkg_put(blkg->parent); + spin_lock_irq(&q->queue_lock); list_del_init(&blkg->q_node); + spin_unlock_irq(&q->queue_lock); mutex_unlock(&q->blkcg_mutex); blk_put_queue(q); -- cgit v1.2.3-59-g8ed1b