From e58de88078e92ca3a97b8f15f95c966b6f1dd714 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Sat, 15 Jun 2013 00:13:11 +0200 Subject: [PATCH] drm/crtc-helpers: Enforce sane set_config api There's no point in trying to clean up after driver-bugs, so just blow up. Furthermore it's an interface abuse to set no mode but have an fb and aslo to try to set an fb without enough connectors. These two spefici cases of interface abuse have been committed by the fb helper, but that's been fixed meanwhile in commit 7e53f3a423146745a4e4bb93362d488dfad502a8 Author: Daniel Vetter Date: Mon Jan 21 10:52:17 2013 +0100 drm/fb-helper: fixup set_config semantics The i915 driver has been shipping since a while with these BUGs with no reports, so should be save. Note that this drops an ugly case where we clear crtc->fb behind the upper levels back and so cause a refcounting mayhem, which Russell Kins spotted while trying to hunt down a drm framebuffer leak. Reported-by: Russell King Signed-off-by: Daniel Vetter Signed-off-by: Dave Airlie --- drivers/gpu/drm/drm_crtc_helper.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c index f554516ec2a4..e57cfece72e4 100644 --- a/drivers/gpu/drm/drm_crtc_helper.c +++ b/drivers/gpu/drm/drm_crtc_helper.c @@ -565,14 +565,13 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set) DRM_DEBUG_KMS("\n"); - if (!set) - return -EINVAL; + BUG_ON(!set); + BUG_ON(!set->crtc); + BUG_ON(!set->crtc->helper_private); - if (!set->crtc) - return -EINVAL; - - if (!set->crtc->helper_private) - return -EINVAL; + /* Enforce sane interface api - has been abused by the fb helper. */ + BUG_ON(!set->mode && set->fb); + BUG_ON(set->fb && set->num_connectors == 0); crtc_funcs = set->crtc->helper_private; -- 2.30.2