Unverified Commit 2200736a authored by Simon Ser's avatar Simon Ser
Browse files

drm: require a non_NULL drm_crtc.primary 



If a CRTC is missing a legacy primary plane pointer, a lot of things
will be broken for user-space: fbdev stops working and the entire legacy
uAPI stops working.

Require all drivers to populate drm_crtc.primary to prevent these
issues. Warn if it's NULL.

Signed-off-by: default avatarSimon Ser <contact@emersion.fr>
Reviewed-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: default avatarPekka Paalanen <pekka.paalanen@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201211184634.74534-3-contact@emersion.fr
parent 6d84576f

drivers/gpu/drm/drm_mode_config.c

+3 −0
Original line number Diff line number Diff line
@@ -639,6 +639,9 @@ void drm_mode_config_validate(struct drm_device *dev) 
	}



	drm_for_each_crtc(crtc, dev) {

		WARN(!crtc->primary, "Missing primary plane on [CRTC:%d:%s]\n",

		     crtc->base.id, crtc->name);



		if (crtc->primary) {

			WARN(!(crtc->primary->possible_crtcs & drm_crtc_mask(crtc)),

			     "Bogus primary plane possible_crtcs: [PLANE:%d:%s] must be compatible with [CRTC:%d:%s]\n",

drivers/gpu/drm/drm_plane.c

+1 −1
Original line number Diff line number Diff line
@@ -57,7 +57,7 @@ 
 * Legacy uAPI doesn't expose the primary and cursor planes directly. DRM core

 * relies on the driver to set the primary and optionally the cursor plane used

 * for legacy IOCTLs. This is done by calling drm_crtc_init_with_planes(). All

 * drivers should provide one primary plane per CRTC to avoid surprising legacy

 * drivers must provide one primary plane per CRTC to avoid surprising legacy

 * userspace too much.

 */