Move hctx cpuhp add/del out of queue freezing for not connecting freeze lock with cpuhp locks, then lockdep warning can be avoided. This way is safe because both needn't queue to be frozen and scheduler switch isn't allowed, with same reason for moving hctx debugfs/sysfs register out of queue freeze. Reviewed-by: Hannes Reinecke <hare@xxxxxxx> Reviewed-by: Nilay Shroff <nilay@xxxxxxxxxxxxx> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> --- block/blk-mq.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 4e6bc065c955..682d75f0a0a4 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -4964,7 +4964,7 @@ static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, fallback: blk_mq_update_queue_map(set); list_for_each_entry(q, &set->tag_list, tag_set_list) { - blk_mq_realloc_hw_ctxs(set, q); + __blk_mq_realloc_hw_ctxs(set, q); if (q->nr_hw_queues != set->nr_hw_queues) { int i = prev_nr_hw_queues; @@ -4988,6 +4988,9 @@ static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, list_for_each_entry(q, &set->tag_list, tag_set_list) { blk_mq_sysfs_register_hctxs(q); blk_mq_debugfs_register_hctxs(q); + + blk_mq_remove_hw_queues_cpuhp(q); + blk_mq_add_hw_queues_cpuhp(q); } memalloc_noio_restore(memflags); -- 2.47.0