------------[ cut here ]------------
WARNING: at /build/buildd/linux-2.6.35/drivers/gpu/drm/radeon/radeon_fence.c:235 radeon_fence_wait+0x365/0x3d0 [radeon]()
Hardware name: P55M-UD2
GPU lockup (waiting for 0x0027022D last fence id 0x0027022B)
Modules linked in: binfmt_misc snd_hda_codec_atihdmi snd_hda_codec_realtek parport_pc ppdev vboxnetadp vboxnetflt vboxdrv kvm_intel kvm joydev hid_logitech ff_memless snd_hda_intel snd_hda_codec firewire_ohci snd_hwdep snd_pcm snd_seq_midi snd_rawmidi radeon snd_seq_midi_event snd_seq snd_timer snd_seq_device ttm drm_kms_helper snd serio_raw drm soundcore i2c_algo_bit snd_page_alloc lp parport usbhid hid ahci r8169 firewire_core libahci crc_itu_t pata_jmicron mii
Pid: 1190, comm: Xorg Not tainted 2.6.35-14-generic #20-Ubuntu
Call Trace:
 [<ffffffff8105f6df>] warn_slowpath_common+0x7f/0xc0
 [<ffffffff8105f7d6>] warn_slowpath_fmt+0x46/0x50
 [<ffffffffa0141575>] radeon_fence_wait+0x365/0x3d0 [radeon]
 [<ffffffff8107e490>] ? autoremove_wake_function+0x0/0x40
 [<ffffffffa0141d71>] radeon_sync_obj_wait+0x11/0x20 [radeon]
 [<ffffffffa00fe1a3>] ttm_bo_wait+0x103/0x1c0 [ttm]
 [<ffffffffa0102641>] ttm_bo_vm_fault+0x231/0x2f0 [ttm]
 [<ffffffffa00cc495>] ? drm_ioctl+0x495/0x4c0 [drm]
 [<ffffffffa0141d1b>] radeon_ttm_fault+0x5b/0x80 [radeon]
 [<ffffffff8111c874>] __do_fault+0x54/0x560
 [<ffffffff81588be5>] ? _raw_spin_lock_irq+0x15/0x20
 [<ffffffff81588be5>] ? _raw_spin_lock_irq+0x15/0x20
 [<ffffffff8111f7a9>] handle_mm_fault+0x1b9/0x440
 [<ffffffff811615ad>] ? vfs_ioctl+0x3d/0xd0
 [<ffffffff8158c8ba>] do_page_fault+0x12a/0x350
 [<ffffffff81589435>] page_fault+0x25/0x30
---[ end trace 80b3239c9abbcbc3 ]---