This is kernel bug and is fixed with kernel commits in 2.6.34-rc1: 7a9f0dd9c49425e2b0e39ada4757bc7a38c84873 drm: Add generic multipart buffer. b4fe945405e477cded91772b4fec854705443dd5 drm/radeon: Fix memory allocation failures in the preKMS command stream checking. 55a5cb5d594c18b3147a2288b00ea359c1a38cf8 drm/radeon: Fix printf type warning in 64bit system.