With multiple inputs through the BRU it is feasible for the streams to
race each other at stream-on.
Multiple VIDIOC_STREAMON calls racing each other could have process
N-1 skipping over the pipeline setup section and then start the pipeline
early, if videobuf2 has already enqueued buffers to the driver for
process N but not called the .start_streaming() operation yet
In the case of the video pipelines, this
can present two serious issues.
1) A null-dereference if the pipe->dl is committed at the same time as
the vsp1_video_setup_pipeline() is processing
2) A hardware hang, where a display list is committed without having
called vsp1_video_setup_pipeline() first
Repair this issue, by ensuring that only the stream which configures the
pipeline is able to start it.
Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
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