There's a logic at the VB2 core that produces a WARN_ON if there are still buffers waiting to be filled. However, it doesn't indicate what buffers are still opened, with makes harder to identify issues inside caller drivers. So, add a new pr_warn() pointing to such buffers. That, together with debug instrumentation inside the drivers can make easier to identify where the problem is. Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx> --- drivers/media/v4l2-core/videobuf2-core.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c index 319ab8bf220f..064d3c6f1e74 100644 --- a/drivers/media/v4l2-core/videobuf2-core.c +++ b/drivers/media/v4l2-core/videobuf2-core.c @@ -1653,8 +1653,11 @@ static void __vb2_queue_cancel(struct vb2_queue *q) */ if (WARN_ON(atomic_read(&q->owned_by_drv_count))) { for (i = 0; i < q->num_buffers; ++i) - if (q->bufs[i]->state == VB2_BUF_STATE_ACTIVE) + if (q->bufs[i]->state == VB2_BUF_STATE_ACTIVE) { + pr_warn("driver bug: stop_streaming operation is leaving buf %p in active state\n", + q->bufs[i]); vb2_buffer_done(q->bufs[i], VB2_BUF_STATE_ERROR); + } /* Must be zero now */ WARN_ON(atomic_read(&q->owned_by_drv_count)); } -- 2.14.3 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html