From 2200736a0c4d3f3195410c1fa95aae579a107d28 Mon Sep 17 00:00:00 2001 From: Simon Ser Date: Fri, 11 Dec 2020 19:46:33 +0100 Subject: [PATCH] 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: Simon Ser Reviewed-by: Daniel Vetter Acked-by: Pekka Paalanen Link: https://patchwork.freedesktop.org/patch/msgid/20201211184634.74534-3-contact@emersion.fr --- drivers/gpu/drm/drm_mode_config.c | 3 +++ drivers/gpu/drm/drm_plane.c | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c index 1628c8b60d9a..1e5da83fd2a8 100644 --- a/drivers/gpu/drm/drm_mode_config.c +++ b/drivers/gpu/drm/drm_mode_config.c @@ -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", diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c index 5d33ca9f0032..49b0a8b9ac02 100644 --- a/drivers/gpu/drm/drm_plane.c +++ b/drivers/gpu/drm/drm_plane.c @@ -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. */ -- 2.11.0