Async plane update is supposed to work only when updating the FB or FB position of an already enabled plane. That does not apply to requests where the plane was previously disabled or assigned to a different CTRC. Check old_plane_state->crtc value to make sure async plane update is allowed. Fixes: fef9df8b5945 ("drm/atomic: initial support for asynchronous plane update") Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx> Reviewed-by: Eric Anholt <eric@xxxxxxxxxx> --- Changes in v2: - Cc stable - Add Eric's R-b --- drivers/gpu/drm/drm_atomic_helper.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 866a2cc72ef6..f7ccfebd3ca8 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -1555,7 +1555,8 @@ int drm_atomic_helper_async_check(struct drm_device *dev, if (n_planes != 1) return -EINVAL; - if (!new_plane_state->crtc) + if (!new_plane_state->crtc || + old_plane_state->crtc != new_plane_state->crtc) return -EINVAL; funcs = plane->helper_private; -- 2.14.1