drm/radeon/kms/agp The wrong AGP chipset can cause a NULL pointer dereference
Selecting the wrong or no CONFIG_AGP_* chipset can cause a NULL pointer
dereference when combined with CONFIG_DRM_RADEON_KMS and an old system
with a R100 AGP card (should effect other cards too). The agp field
will be set to NULL if no suitable AGP chipset driver is loaded,
drm_agp_acquire already preforms a suitable NULL check so it can be used
directly.
Signed-off-by: Robert Fitzsimons <robfitz@273k.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon_agp.c b/drivers/gpu/drm/radeon/radeon_agp.c
index c445779..28e473f 100644
--- a/drivers/gpu/drm/radeon/radeon_agp.c
+++ b/drivers/gpu/drm/radeon/radeon_agp.c
@@ -134,12 +134,10 @@
int ret;
/* Acquire AGP. */
- if (!rdev->ddev->agp->acquired) {
- ret = drm_agp_acquire(rdev->ddev);
- if (ret) {
- DRM_ERROR("Unable to acquire AGP: %d\n", ret);
- return ret;
- }
+ ret = drm_agp_acquire(rdev->ddev);
+ if (ret) {
+ DRM_ERROR("Unable to acquire AGP: %d\n", ret);
+ return ret;
}
ret = drm_agp_info(rdev->ddev, &info);