diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 5009af490a0..b19cd684bf1 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -1749,6 +1749,12 @@ static struct cfq_queue *cfq_close_cooperator(struct cfq_data *cfqd,
 	if (CFQQ_SEEKY(cur_cfqq))
 		return NULL;
 
+	/*
+	 * Don't search priority tree if it's the only queue in the group.
+	 */
+	if (cur_cfqq->cfqg->nr_cfqq == 1)
+		return NULL;
+
 	/*
 	 * We should notice if some of the queues are cooperating, eg
 	 * working closely on the same area of the disk. In that case,