Commit 2ca7d93b authored Oct 30, 2005 by Nate Diller Committed by Linus Torvalds Oct 30, 2005

[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>

parent 3fa63c7d

drivers/block/elevator.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -753,8 +753,10 @@ ssize_t elv_iosched_store(request_queue_t q, const char name, size_t count)
		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;