[PATCH] block cleanups: Fix iosched module refcount leak
If the requested I/O scheduler is already in place, elevator_switch simply
leaves the queue alone, and returns. However, it forgets to call
elevator_put, so
'echo [current_sched] > /sys/block/[dev]/queue/scheduler'
will leak a reference, causing the current_sched module to be permanently
pinned in memory.
Signed-off-by: Nate Diller <nate@namesys.com>
Acked-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/block/elevator.c b/drivers/block/elevator.c
index 3b652eb..36f1057 100644
--- a/drivers/block/elevator.c
+++ b/drivers/block/elevator.c
@@ -753,8 +753,10 @@
return -EINVAL;
}
- if (!strcmp(elevator_name, q->elevator->elevator_type->elevator_name))
+ if (!strcmp(elevator_name, q->elevator->elevator_type->elevator_name)) {
+ elevator_put(e);
return count;
+ }
elevator_switch(q, e);
return count;
