------------[ cut here ]------------
WARNING: at /build/buildd/linux-2.6.35/lib/kref.c:34 kref_get+0x21/0x30()
Hardware name: Aspire 5720Z    
Modules linked in: binfmt_misc parport_pc ppdev vboxnetadp vboxnetflt vboxdrv snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_seq_midi i915 snd_rawmidi snd_seq_midi_event snd_seq joydev lib80211_crypt_tkip drm_kms_helper wl(P) snd_timer snd_seq_device r852 drm sm_common nand nand_ids nand_ecc mtd lirc_ene0100(+) i2c_algo_bit intel_agp lirc_dev video snd soundcore snd_page_alloc psmouse serio_raw lib80211 agpgart output lp parport usbhid hid usb_storage firewire_ohci ahci firewire_core sdhci_pci tg3 sdhci led_class crc_itu_t libahci
Pid: 1056, comm: Xorg Tainted: P      D     2.6.35-17-generic #23-Ubuntu
Call Trace:
 [<c014a812>] warn_slowpath_common+0x72/0xa0
 [<c03528f1>] ? kref_get+0x21/0x30
 [<c03528f1>] ? kref_get+0x21/0x30
 [<c014a862>] warn_slowpath_null+0x22/0x30
 [<c03528f1>] kref_get+0x21/0x30
 [<f81ce2a3>] drm_gem_handle_create+0x83/0xa0 [drm]
 [<c05c6199>] ? mutex_lock+0x19/0x40
 [<f82ea755>] intel_user_framebuffer_create_handle+0x15/0x20 [i915]
 [<f81d78c9>] drm_mode_getfb+0x69/0xa0 [drm]
 [<c01c64ad>] ? event_format_read+0xcd/0x280
 [<f81cc987>] drm_ioctl+0x1a7/0x400 [drm]
 [<c01c64ad>] ? event_format_read+0xcd/0x280
 [<f81d7860>] ? drm_mode_getfb+0x0/0xa0 [drm]
 [<c032e006>] ? apparmor_file_permission+0x16/0x20
 [<c03024d4>] ? security_file_permission+0x14/0x20
 [<c0218082>] ? rw_verify_area+0x62/0xd0
 [<c01c64ad>] ? event_format_read+0xcd/0x280
 [<c02260d2>] vfs_ioctl+0x32/0xb0
 [<f81cc7e0>] ? drm_ioctl+0x0/0x400 [drm]
 [<c0226969>] do_vfs_ioctl+0x79/0x2d0
 [<c0226c27>] sys_ioctl+0x67/0x80
 [<c01c64ad>] ? event_format_read+0xcd/0x280
 [<c05c78c4>] syscall_call+0x7/0xb
 [<c01c64ad>] ? event_format_read+0xcd/0x280
 [<c01c64ad>] ? event_format_read+0xcd/0x280
---[ end trace 4928562ce252ec86 ]---