@@ -414,6 +414,17 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
vb->index = q->num_buffers + buffer;
vb->type = q->type;
vb->memory = memory;
+ /*
+ * We need to set these flags here so that the videobuf2 core
+ * will call ->prepare()/->finish() cache sync/flush on vb2
+ * buffers when appropriate. However, we can avoid explicit
+ * ->prepare() and ->finish() cache sync for DMABUF buffers,
+ * because DMA exporter takes care of it.
+ */
+ if (q->memory != VB2_MEMORY_DMABUF) {
+ vb->need_cache_sync_on_prepare = 1;
+ vb->need_cache_sync_on_finish = 1;
+ }
for (plane = 0; plane < num_planes; ++plane) {
vb->planes[plane].length = plane_sizes[plane];
vb->planes[plane].min_length = plane_sizes[plane];
We need to set ->need_cache_sync_on_prepare and ->need_cache_sync_on_finish when we initialize vb2 buffer. Currently these flags are set/adjusted only in V4L2's vb2_queue_or_prepare_buf(), which means that for the code paths that don't use V4L2 vb2 will always tell videobuf2 core to skip ->prepare() and ->finish() cache syncs/flushes. Fix this by setting cache sync hints for new buffers; except VB2_MEMORY_DMABUF buffers, for which DMA exporter syncs caches. Fixes: f5f5fa73fbfb ("media: videobuf2: handle V4L2 buffer cache flags") Reported-by: Tomasz Figa <tfiga@chromium.org> Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> --- drivers/media/common/videobuf2/videobuf2-core.c | 11 +++++++++++ 1 file changed, 11 insertions(+)