4.9-stable review patch. If anyone has any objections, please let me know.
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From: Hans Verkuil hverkuil-cisco@xs4all.nl
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@xs4all.nl Acked-by: Ezequiel Garcia ezequiel@collabora.com Signed-off-by: Mauro Carvalho Chehab mchehab+samsung@kernel.org Cc: Matthias Maennich maennich@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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 @@ -146,7 +146,6 @@ static void vb2_warn_zero_bytesused(stru return;
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)