The topology that v4l2_m2m_register_media_controller() creates for a processing block actually created a source-to-source link and a sink-to-sink link instead of two source-to-sink links. Unfortunately v4l2-compliance never checked for such bad links, so this went unreported for quite some time. Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> Reported-by: Nicolas Dufresne <nicolas@xxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # for v4.19 and up --- diff --git a/drivers/media/v4l2-core/v4l2-mem2mem.c b/drivers/media/v4l2-core/v4l2-mem2mem.c index 1afd9c6ad908..cc34c5ab7009 100644 --- a/drivers/media/v4l2-core/v4l2-mem2mem.c +++ b/drivers/media/v4l2-core/v4l2-mem2mem.c @@ -880,12 +880,12 @@ int v4l2_m2m_register_media_controller(struct v4l2_m2m_dev *m2m_dev, goto err_rel_entity1; /* Connect the three entities */ - ret = media_create_pad_link(m2m_dev->source, 0, &m2m_dev->proc, 1, + ret = media_create_pad_link(m2m_dev->source, 0, &m2m_dev->proc, 0, MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED); if (ret) goto err_rel_entity2; - ret = media_create_pad_link(&m2m_dev->proc, 0, &m2m_dev->sink, 0, + ret = media_create_pad_link(&m2m_dev->proc, 1, &m2m_dev->sink, 0, MEDIA_LNK_FL_IMMUTABLE | MEDIA_LNK_FL_ENABLED); if (ret) goto err_rm_links0;
