diff --git a/libweston/backend-drm/drm-internal.h b/libweston/backend-drm/drm-internal.h
index e008a8d13..bd350240a 100644
--- a/libweston/backend-drm/drm-internal.h
+++ b/libweston/backend-drm/drm-internal.h
@@ -354,6 +354,7 @@ struct drm_output_state {
 	enum weston_hdcp_protection protection;
 	struct wl_list plane_list;
 	bool tear;
+	bool planes_enabled;
 };
 
 /**
diff --git a/libweston/backend-drm/state-propose.c b/libweston/backend-drm/state-propose.c
index 99a260c37..45bab8faf 100644
--- a/libweston/backend-drm/state-propose.c
+++ b/libweston/backend-drm/state-propose.c
@@ -890,6 +890,7 @@ drm_output_propose_state(struct weston_output *output_base,
 					   pending_state,
 					   DRM_OUTPUT_STATE_CLEAR_PLANES);
 	state->dpms = WESTON_DPMS_ON;
+	state->planes_enabled = !output_base->disable_planes;
 
 	/* Start with the assumption that we're going to do a tearing commit,
 	 * if the hardware supports it and we're not compositing with the
@@ -1249,6 +1250,8 @@ drm_assign_planes(struct weston_output *output_base)
 	}
 
 	assert(state);
+	assert(state->planes_enabled == !output_base->disable_planes);
+
 	drm_debug(b, "\t[repaint] Using %s composition\n",
 		  drm_propose_state_mode_to_string(mode));