From: Yu Kuai yukuai3@huawei.com

mainline inclusion from mainline-5.14-rc6 commit 454bb6775202d94f0f489c4632efecdb62d3c904 category: bugfix bugzilla: 175277 CVE: NA

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We run a test that delete and recover devcies frequently(two devices on the same host), and we found that 'active_queues' is super big after a period of time.

If device a and device b share a tag set, and a is deleted, then blk_mq_exit_queue() will clear BLK_MQ_F_TAG_QUEUE_SHARED because there is only one queue that are using the tag set. However, if b is still active, the active_queues of b might never be cleared even if b is deleted.

Thus clear active_queues before BLK_MQ_F_TAG_QUEUE_SHARED is cleared.

Signed-off-by: Yu Kuai yukuai3@huawei.com Reviewed-by: Ming Lei ming.lei@redhat.com Link: https://lore.kernel.org/r/20210731062130.1533893-1-yukuai3@huawei.com Signed-off-by: Jens Axboe axboe@kernel.dk

Conflict: block/blk-mq.c Signed-off-by: Yu Kuai yukuai3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- block/blk-mq.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c index b5b41b9a72294..f23500becbc80 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2516,10 +2516,12 @@ static void queue_set_hctx_shared(struct request_queue *q, bool shared) int i;

queue_for_each_hw_ctx(q, hctx, i) { - if (shared) + if (shared) { hctx->flags |= BLK_MQ_F_TAG_SHARED; - else + } else { + blk_mq_tag_idle(hctx); hctx->flags &= ~BLK_MQ_F_TAG_SHARED; + } } }