4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Boris Brezillon <boris.brezillon@xxxxxxxxxxx> commit fcc86cb45d38ca2f24bcea9c29c7f4742041caed upstream. drm_atomic_helper_setup_commit() auto-completes commit->flip_done when state->legacy_cursor_update is true, but we know for sure that we want a sync update when we call drm_atomic_helper_setup_commit() from vc4_atomic_commit(). Explicitly set state->legacy_cursor_update to false to prevent this auto-completion. Fixes: 184d3cf4f738 ("drm/vc4: Use wait_for_flip_done() instead of wait_for_vblanks()") Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx> Reviewed-by: Eric Anholt <eric@xxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20181115105852.9844-2-boris.brezillon@xxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/vc4/vc4_kms.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/gpu/drm/vc4/vc4_kms.c +++ b/drivers/gpu/drm/vc4/vc4_kms.c @@ -216,6 +216,12 @@ static int vc4_atomic_commit(struct drm_ return 0; } + /* We know for sure we don't want an async update here. Set + * state->legacy_cursor_update to false to prevent + * drm_atomic_helper_setup_commit() from auto-completing + * commit->flip_done. + */ + state->legacy_cursor_update = false; ret = drm_atomic_helper_setup_commit(state, nonblock); if (ret) return ret;