[PATCH 4.14 066/183] media: videobuf2-v4l2: drop WARN_ON in vb2_warn_zero_bytesused()

From: Greg Kroah-Hartman
Date: Fri Mar 22 2019 - 07:49:25 EST

4.14-stable review patch. If anyone has any objections, please let me know.


From: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>

commit 5e99456c20f712dcc13d9f6ca4278937d5367355 upstream.

Userspace shouldn't set bytesused to 0 for output buffers.
vb2_warn_zero_bytesused() warns about this (only once!), but it also
calls WARN_ON(1), which is confusing since it is not immediately clear
that it warns about a 0 value for bytesused.

Just drop the WARN_ON as it serves no purpose.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Acked-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
Cc: Matthias Maennich <maennich@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

drivers/media/v4l2-core/videobuf2-v4l2.c | 1 -
1 file changed, 1 deletion(-)

--- a/drivers/media/v4l2-core/videobuf2-v4l2.c
+++ b/drivers/media/v4l2-core/videobuf2-v4l2.c
@@ -145,7 +145,6 @@ static void vb2_warn_zero_bytesused(stru

check_once = true;
- WARN_ON(1);

pr_warn("use of bytesused == 0 is deprecated and will be removed in the future,\n");
if (vb->vb2_queue->allow_zero_bytesused)