The current order of locking between the driver mutex and the v4l2
subdev state lock causes a circuluar locking dependency when trying to
set up a link. Fix this.
Signed-off-by: Paul Elder <paul.elder@xxxxxxxxxxxxxxxx>
---
drivers/media/platform/video-mux.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/media/platform/video-mux.c b/drivers/media/platform/video-mux.c
index 31e9e92e723eb..f43849db56800 100644
--- a/drivers/media/platform/video-mux.c
+++ b/drivers/media/platform/video-mux.c
@@ -52,6 +52,7 @@ static int video_mux_link_setup(struct media_entity *entity,
const struct media_pad *remote, u32 flags)
{
struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
+ struct v4l2_subdev_state *sd_state;
struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
u16 source_pad = entity->num_pads - 1;
int ret = 0;
@@ -67,10 +68,10 @@ static int video_mux_link_setup(struct media_entity *entity,
remote->entity->name, remote->index, local->entity->name,
local->index, flags & MEDIA_LNK_FL_ENABLED);
+ sd_state = v4l2_subdev_lock_and_get_active_state(sd);
mutex_lock(&vmux->lock);
if (flags & MEDIA_LNK_FL_ENABLED) {
- struct v4l2_subdev_state *sd_state;
struct v4l2_mbus_framefmt *source_mbusformat;
if (vmux->active == local->index)
@@ -88,12 +89,10 @@ static int video_mux_link_setup(struct media_entity *entity,
vmux->active = local->index;
/* Propagate the active format to the source */
- sd_state = v4l2_subdev_lock_and_get_active_state(sd);
source_mbusformat = v4l2_subdev_state_get_format(sd_state,
source_pad);
*source_mbusformat = *v4l2_subdev_state_get_format(sd_state,
vmux->active);
- v4l2_subdev_unlock_state(sd_state);
} else {
if (vmux->active != local->index)
goto out;
@@ -105,6 +104,7 @@ static int video_mux_link_setup(struct media_entity *entity,
out:
mutex_unlock(&vmux->lock);
+ v4l2_subdev_unlock_state(sd_state);
return ret;
}
--
2.39.2
