blk-mq-sched: Fix blk_mq_sched_alloc_tags() error handling

If the blk_mq_sched_alloc_tags() -> blk_mq_alloc_rqs() call fails, then we call blk_mq_sched_free_tags() -> blk_mq_free_rqs(). It is incorrect to do so, as any rqs would have already been freed in the blk_mq_alloc_rqs() call. Fix by calling blk_mq_free_rq_map() only directly. Fixes: 6917ff0 ("blk-mq-sched: refactor scheduler initialization") Signed-off-by: John Garry <[email protected]> Reviewed-by: Ming Lei <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jens Axboe <[email protected]>
otyshchenko1 · Jul 27, 2021 · b93af30 · b93af30
1 parent 3ce6e1f
commit b93af30
Showing 1 changed file with 4 additions and 13 deletions.
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
@@ -515,17 +515,6 @@ void blk_mq_sched_insert_requests(struct blk_mq_hw_ctx *hctx,
 	percpu_ref_put(&q->q_usage_counter);
 }
 
-static void blk_mq_sched_free_tags(struct blk_mq_tag_set *set,
-				   struct blk_mq_hw_ctx *hctx,
-				   unsigned int hctx_idx)
-{
-	if (hctx->sched_tags) {
-		blk_mq_free_rqs(set, hctx->sched_tags, hctx_idx);
-		blk_mq_free_rq_map(hctx->sched_tags, set->flags);
-		hctx->sched_tags = NULL;
-	}
-}
-
 static int blk_mq_sched_alloc_tags(struct request_queue *q,
 				   struct blk_mq_hw_ctx *hctx,
 				   unsigned int hctx_idx)
@@ -539,8 +528,10 @@ static int blk_mq_sched_alloc_tags(struct request_queue *q,
 		return -ENOMEM;
 
 	ret = blk_mq_alloc_rqs(set, hctx->sched_tags, hctx_idx, q->nr_requests);
-	if (ret)
-		blk_mq_sched_free_tags(set, hctx, hctx_idx);
+	if (ret) {
+		blk_mq_free_rq_map(hctx->sched_tags, set->flags);
+		hctx->sched_tags = NULL;
+	}
 
 	return ret;
 }