------------[ cut here ]------------
WARNING: at /build/buildd/linux-2.6.38/drivers/gpu/drm/radeon/radeon_fence.c:248 radeon_fence_wait+0x2ea/0x350 [radeon]()
Hardware name: Aspire 5500                     
GPU lockup (waiting for 0x00000005 last fence id 0x00000001)
Modules linked in: michael_mic arc4 lib80211_crypt_tkip snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq binfmt_misc lm90 ipw2200 pcmcia snd_timer snd_seq_device libipw ppdev irda cfg80211 radeon ttm drm_kms_helper drm parport_pc snd yenta_socket pcmcia_rsrc crc_ccitt psmouse soundcore pcmcia_core i2c_algo_bit lib80211 video serio_raw snd_page_alloc lp parport usbhid hid firewire_ohci tg3 sdhci_pci firewire_core sdhci crc_itu_t
Pid: 1640, comm: Xorg Not tainted 2.6.38-8-generic #42-Ubuntu
Call Trace:
 [<c104f912>] ? warn_slowpath_common+0x72/0xa0
 [<f869b66a>] ? radeon_fence_wait+0x2ea/0x350 [radeon]
 [<f869b66a>] ? radeon_fence_wait+0x2ea/0x350 [radeon]
 [<c104f9e3>] ? warn_slowpath_fmt+0x33/0x40
 [<f869b66a>] ? radeon_fence_wait+0x2ea/0x350 [radeon]
 [<c106d370>] ? autoremove_wake_function+0x0/0x50
 [<f869bed1>] ? radeon_sync_obj_wait+0x11/0x20 [radeon]
 [<f81ee719>] ? ttm_bo_wait+0xd9/0x170 [ttm]
 [<f86b2d52>] ? radeon_gem_wait_idle_ioctl+0x82/0xe0 [radeon]
 [<f8536cd1>] ? drm_ioctl+0x1e1/0x470 [drm]
 [<f86b2cd0>] ? radeon_gem_wait_idle_ioctl+0x0/0xe0 [radeon]
 [<c100bde0>] ? restore_i387_xstate+0xf0/0x210
 [<c1105881>] ? do_mmap_pgoff+0x231/0x300
 [<f8536af0>] ? drm_ioctl+0x0/0x470 [drm]
 [<c11367cb>] ? do_vfs_ioctl+0x7b/0x2e0
 [<c100225e>] ? restore_sigcontext+0xbe/0xe0
 [<c1136ab7>] ? sys_ioctl+0x87/0x90
 [<c1509bf4>] ? syscall_call+0x7/0xb
---[ end trace b2c1adfe81cd0fb6 ]---