rq_qos_del() incorrectly assigns the node being deleted to the head if
it was the first on the list in the !prev path. Fix it by iterating
with ** instead.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Fixes: a79050434b45 ("blk-rq-qos: refactor out common elements of blk-wbt")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
static inline void rq_qos_del(struct request_queue *q, struct rq_qos *rqos)
{
- struct rq_qos *cur, *prev = NULL;
- for (cur = q->rq_qos; cur; cur = cur->next) {
- if (cur == rqos) {
- if (prev)
- prev->next = rqos->next;
- else
- q->rq_qos = cur;
+ struct rq_qos **cur;
+
+ for (cur = &q->rq_qos; *cur; cur = &(*cur)->next) {
+ if (*cur == rqos) {
+ *cur = rqos->next;
break;
}
- prev = cur;
}
blk_mq_debugfs_unregister_rqos(rqos);