drm/atomic-helper: WARN if legacy plane fb pointers are bogus when committing duplicated state

drm_atomic_helper_commit_duplicated_state() should only be called
resume/reset/load_detect paths where plane->old_fb should always be
NULL and plane->fb should be equal to the new_plane_state->fb.
Assert that is indeed the case.

Cc: [email protected]
Cc: [email protected]
Cc: Dave Airlie <[email protected]> (v1)
Cc: Maarten Lankhorst <[email protected]>
Cc: Daniel Vetter <[email protected]>
Signed-off-by: Ville Syrjälä <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
Reviewed-by: Daniel Vetter <[email protected]>
Reviewed-by: Maarten Lankhorst <[email protected]>

1 files changed, 6 insertions, 1 deletions

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index ef4ddfecc4a4..fe09d6254c19 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -3118,8 +3118,13 @@ int drm_atomic_helper_commit_duplicated_state(struct drm_atomic_state *state,
 
 	state->acquire_ctx = ctx;
 
-	for_each_new_plane_in_state(state, plane, new_plane_state, i)
+	for_each_new_plane_in_state(state, plane, new_plane_state, i) {
+		WARN_ON(plane->crtc != new_plane_state->crtc);
+		WARN_ON(plane->fb != new_plane_state->fb);
+		WARN_ON(plane->old_fb);
+
 		state->planes[i].old_state = plane->state;
+	}
 
 	for_each_new_crtc_in_state(state, crtc, new_crtc_state, i)
 		state->crtcs[i].old_state = crtc->state;