4.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Boris Brezillon <boris.brezillon@xxxxxxxxxxx> commit 603ba2dfb338b307aebe95fe344c479a59b3a175 upstream. 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> Link: https://patchwork.freedesktop.org/patch/msgid/20180724133215.31917-1-boris.brezillon@xxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/drm_atomic_helper.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -1516,7 +1516,8 @@ int drm_atomic_helper_async_check(struct 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;