static int blk_mq_init_hw_queues(struct request_queue *q,
		struct blk_mq_tag_set *set)
{
	struct blk_mq_hw_ctx *hctx;
	unsigned int i;

	/*
	 * Initialize hardware queues
	 */
	queue_for_each_hw_ctx(q, hctx, i) {
		if (blk_mq_init_hctx(q, set, hctx, i))
			break;
	}

	if (i == q->nr_hw_queues)
		return 0;

	/*
	 * Init failed
	 */
	blk_mq_exit_hw_queues(q, set, i);

	return 1;
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.