From: Ming Lin <ming.l@xxxxxxxxxxx>
blk_mq_init_queue() calls blk_mq_init_allocated_queue(), but q->mq_ops
was not cleared when blk_mq_init_allocated_queue() fails.
Then blk_cleanup_queue() calls blk_mq_free_queue() which will crash because:
- q->all_q_node is not added to all_q_list yet
- q->tag_set is NULL
- hctx was not setup yet or already freed
Fixed it by clearing q->mq_ops on error path.