Comment 36 for bug 968520

Still failing in 3.6-rc3. Every 5 seconds in X there's a freeze (except for the mouse pointer), and then re-rendering tainted areas of the screen is erratic.

dmesg says:

   56.148632] ------------[ cut here ]------------
[ 56.148660] WARNING: at /home/apw/COD/linux/drivers/gpu/drm/i915/intel_pm.c:4009 gen6_gt_check_fifodbg+0x3e/0x60 [i915]()
[ 56.148662] Hardware name: To Be Filled By O.E.M.
[ 56.148663] MMIO read or write has been dropped 2
[ 56.148664] Modules linked in: hidp ipt_MASQUERADE iptable_nat nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack iptable_filter ip_tables x_tables ipx p8022 psnap llc p8023 dm_crypt snd_hda_codec_hdmi snd_hda_codec_realtek bnep rfcomm parport_pc ppdev binfmt_misc nfsd nfs_acl nfsv4 auth_rpcgss nfs fscache lockd sunrpc joydev hid_generic btusb bluetooth coretemp kvm_intel kvm snd_hda_intel snd_hda_codec snd_hwdep psmouse microcode snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq snd_timer snd_seq_device serio_raw snd lpc_ich soundcore snd_page_alloc mac_hid mei lp parport uvesafb hid_apple aesni_intel ablk_helper cryptd aes_i586 usbhid hid i915 r8169 drm_kms_helper drm i2c_algo_bit video
[ 56.148692] Pid: 1392, comm: Xorg Tainted: G W 3.6.0-030600rc3-generic #201208221735
[ 56.148693] Call Trace:
[ 56.148699] [<c1049512>] warn_slowpath_common+0x72/0xa0
[ 56.148710] [<f859ba4e>] ? gen6_gt_check_fifodbg+0x3e/0x60 [i915]
[ 56.148719] [<f859ba4e>] ? gen6_gt_check_fifodbg+0x3e/0x60 [i915]
[ 56.148722] [<c10495e3>] warn_slowpath_fmt+0x33/0x40
[ 56.148731] [<f859ba4e>] gen6_gt_check_fifodbg+0x3e/0x60 [i915]
[ 56.148741] [<f859bac1>] __gen6_gt_force_wake_put+0x21/0x30 [i915]
[ 56.148747] [<f855dd40>] i915_read32+0x110/0x130 [i915]
[ 56.148757] [<f85a035c>] intel_ring_get_active_head+0x2c/0x30 [i915]
[ 56.148766] [<f85a0397>] gen6_ring_get_seqno+0x37/0x50 [i915]
[ 56.148773] [<f856eb6d>] i915_gem_retire_requests_ring+0x2d/0x250 [i915]
[ 56.148777] [<c15e0e40>] ? mutex_lock_interruptible+0x10/0x40
[ 56.148784] [<f856f7f6>] i915_gem_object_flush_active+0x66/0x70 [i915]
[ 56.148792] [<f8571fe3>] i915_gem_busy_ioctl+0x53/0xa0 [i915]
[ 56.148795] [<c12d75c2>] ? _copy_from_user+0x42/0x60
[ 56.148802] [<f8488e88>] drm_ioctl+0x408/0x470 [drm]
[ 56.148812] [<f8571f90>] ? i915_gem_unpin_ioctl+0xf0/0xf0 [i915]
[ 56.148815] [<c12d2a97>] ? timerqueue_del+0x27/0x70
[ 56.148817] [<c106e390>] ? __remove_hrtimer+0x40/0xa0
[ 56.148819] [<c106eba2>] ? hrtimer_try_to_cancel+0x42/0xb0
[ 56.148821] [<c105039b>] ? do_setitimer+0x13b/0x230
[ 56.148823] [<c12d74cf>] ? __copy_from_user_ll+0x1f/0x40
[ 56.148829] [<f8488a80>] ? drm_copy_field+0x80/0x80 [drm]
[ 56.148832] [<c1162d4f>] do_vfs_ioctl+0x7f/0x2f0
[ 56.148834] [<c12d73df>] ? __copy_to_user_ll+0x1f/0x40
[ 56.148836] [<c116302f>] sys_ioctl+0x6f/0x80
[ 56.148838] [<c15e9c9f>] sysenter_do_call+0x12/0x28
[ 56.148840] ---[ end trace 7ee6e6596296fef6 ]---
[ 62.163513] [drm:i915_hangcheck_hung] *ERROR* Hangcheck timer elapsed... GPU hung
[ 62.163516] [drm] capturing error event; look for more information in /debug/dri/0/i915_error_state