Commit e43d76b4 authored Apr 22, 2008 by Brandon Philips Committed by Mauro Carvalho Chehab Apr 24, 2008

V4L/DVB (7281): v4l: Deadlock in videobuf-core for DQBUF waiting on QBUF

Avoid a deadlock where DQBUF is holding the vb_lock while waiting on a QBUF
which also needs the vb_lock. Reported by Hans Verkuil <hverkuil@xs4all.nl>.

Signed-off-by: Brandon Philips <bphilips@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

parent 9dc4e48f

drivers/media/video/videobuf-core.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -605,7 +605,9 @@ int videobuf_dqbuf(struct videobuf_queue *q,
		goto done;
		}
		buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
		mutex_unlock(&q->vb_lock);
		retval = videobuf_waiton(buf, nonblocking, 1);
		mutex_lock(&q->vb_lock);
		if (retval < 0) {
		dprintk(1, "dqbuf: waiton returned %d\n", retval);
		goto done;