On 03/01/17 13:36, Laurent Pinchart wrote:
> Hi Kieran,
>
> Thank you for the patch.
>
> On Tuesday 03 Jan 2017 13:12:11 Kieran Bingham wrote:
>> Drivers must not perform unbalanced calls to stop the entity pipeline,
>> however if they do they will fault in the core media code, as the
>> entity->pipe will be set as NULL. We handle this gracefully in the core
>> with a WARN for the developer.
>>
>> Replace the erroneous check on zero streaming counts, with a check on
>> NULL pipe elements instead, as this is the symptom of unbalanced
>> media_pipeline_stop calls.
>>
>> Signed-off-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
>
> This looks good to me,
>
> Acked-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
>
> I'll let Sakari review and merge the patch.
Ahh, yes - I forgot to mention, although perhaps it will be obvious for
Sakari - but this patch is based on top of Sakari's pending media
pipeline and graph walk cleanup series :D
--
Regards
Kieran
>
>> ---
>> drivers/media/media-entity.c | 7 ++++++-
>> 1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/media/media-entity.c b/drivers/media/media-entity.c
>> index caa13e6f09f5..cb1fb2c17f85 100644
>> --- a/drivers/media/media-entity.c
>> +++ b/drivers/media/media-entity.c
>> @@ -534,8 +534,13 @@ void __media_pipeline_stop(struct media_entity *entity)
>> struct media_graph *graph = &entity->pipe->graph;
>> struct media_pipeline *pipe = entity->pipe;
>>
>> + /*
>> + * If the following check fails, the driver has performed an
>> + * unbalanced call to media_pipeline_stop()
>> + */
>> + if (WARN_ON(!pipe))
>> + return;
>>
>> - WARN_ON(!pipe->streaming_count);
>> media_graph_walk_start(graph, entity);
>>
>> while ((entity = media_graph_walk_next(graph))) {
>
