1. 12 1月, 2017 1 次提交
  2. 29 10月, 2016 2 次提交
  3. 24 10月, 2016 1 次提交
    • C
      drm/i915: Move user fault tracking to a separate list · 275f039d
      Chris Wilson 提交于
      We want to decouple RPM and struct_mutex, but currently RPM has to walk
      the list of bound objects and remove userspace mmapping before we
      suspend (otherwise userspace may continue to access the GTT whilst it is
      powered down). This currently requires the struct_mutex to walk the
      bound_list, but if we move that to a separate list and lock we can take
      the first step towards removing the struct_mutex.
      
      v2: Split runtime suspend unmapping vs regular unmapping, to make the
      locking (and barriers) clearer. Add the object to the userfault_list
      prior to inserting the first PTE, the race between add/revoke depends
      upon struct_mutex for regular unmappings and rpm for runtime-suspend.
      Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
      Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> #v1
      Link: http://patchwork.freedesktop.org/patch/msgid/20161024124218.18252-1-chris@chris-wilson.co.uk
      275f039d
  4. 14 10月, 2016 1 次提交
    • A
      drm/i915: Allocate intel_engine_cs structure only for the enabled engines · 3b3f1650
      Akash Goel 提交于
      With the possibility of addition of many more number of rings in future,
      the drm_i915_private structure could bloat as an array, of type
      intel_engine_cs, is embedded inside it.
      	struct intel_engine_cs engine[I915_NUM_ENGINES];
      Though this is still fine as generally there is only a single instance of
      drm_i915_private structure used, but not all of the possible rings would be
      enabled or active on most of the platforms. Some memory can be saved by
      allocating intel_engine_cs structure only for the enabled/active engines.
      Currently the engine/ring ID is kept static and dev_priv->engine[] is simply
      indexed using the enums defined in intel_engine_id.
      To save memory and continue using the static engine/ring IDs, 'engine' is
      defined as an array of pointers.
      	struct intel_engine_cs *engine[I915_NUM_ENGINES];
      dev_priv->engine[engine_ID] will be NULL for disabled engine instances.
      
      There is a text size reduction of 928 bytes, from 1028200 to 1027272, for
      i915.o file (but for i915.ko file text size remain same as 1193131 bytes).
      
      v2:
      - Remove the engine iterator field added in drm_i915_private structure,
        instead pass a local iterator variable to the for_each_engine**
        macros. (Chris)
      - Do away with intel_engine_initialized() and instead directly use the
        NULL pointer check on engine pointer. (Chris)
      
      v3:
      - Remove for_each_engine_id() macro, as the updated macro for_each_engine()
        can be used in place of it. (Chris)
      - Protect the access to Render engine Fault register with a NULL check, as
        engine specific init is done later in Driver load sequence.
      
      v4:
      - Use !!dev_priv->engine[VCS] style for the engine check in getparam. (Chris)
      - Kill the superfluous init_engine_lists().
      
      v5:
      - Cleanup the intel_engines_init() & intel_engines_setup(), with respect to
        allocation of intel_engine_cs structure. (Chris)
      
      v6:
      - Rebase.
      
      v7:
      - Optimize the for_each_engine_masked() macro. (Chris)
      - Change the type of 'iter' local variable to enum intel_engine_id. (Chris)
      - Rebase.
      
      v8: Rebase.
      
      v9: Rebase.
      
      v10:
      - For index calculation use engine ID instead of pointer based arithmetic in
        intel_engine_sync_index() as engine pointers are not contiguous now (Chris)
      - For appropriateness, rename local enum variable 'iter' to 'id'. (Joonas)
      - Use for_each_engine macro for cleanup in intel_engines_init() and remove
        check for NULL engine pointer in cleanup() routines. (Joonas)
      
      v11: Rebase.
      
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Signed-off-by: NAkash Goel <akash.goel@intel.com>
      Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
      Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
      Link: http://patchwork.freedesktop.org/patch/msgid/1476378888-7372-1-git-send-email-akash.goel@intel.com
      3b3f1650
  5. 09 9月, 2016 2 次提交
  6. 19 8月, 2016 1 次提交
  7. 05 8月, 2016 5 次提交
  8. 04 8月, 2016 1 次提交
  9. 20 7月, 2016 2 次提交
  10. 16 7月, 2016 1 次提交
  11. 24 6月, 2016 2 次提交
  12. 09 5月, 2016 1 次提交
  13. 26 2月, 2016 1 次提交
  14. 09 12月, 2015 1 次提交
    • C
      drm/i915: Add soft-pinning API for execbuffer · 506a8e87
      Chris Wilson 提交于
      Userspace can pass in an offset that it presumes the object is located
      at. The kernel will then do its utmost to fit the object into that
      location. The assumption is that userspace is handling its own object
      locations (for example along with full-ppgtt) and that the kernel will
      rarely have to make space for the user's requests.
      Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
      
      v2: Fixed incorrect eviction found by Michal Winiarski - fix suggested by Chris
      Wilson.  Fixed incorrect error paths causing crash found by Michal Winiarski.
      (Not published externally)
      
      v3: Rebased because of trivial conflict in object_bind_to_vm.  Fixed eviction
      to allow eviction of soft-pinned objects when another soft-pinned object used
      by a subsequent execbuffer overlaps reported by Michal Winiarski.
      (Not published externally)
      
      v4: Moved soft-pinned objects to the front of ordered_vmas so that they are
      pinned first after an address conflict happens to avoid repeated conflicts in
      rare cases (Suggested by Chris Wilson).  Expanded comment on
      drm_i915_gem_exec_object2.offset to cover this new API.
      
      v5: Added I915_PARAM_HAS_EXEC_SOFTPIN parameter for detecting this capability
      (Kristian). Added check for multiple pinnings on eviction (Akash). Made sure
      buffers are not considered misplaced without the user specifying
      EXEC_OBJECT_SUPPORTS_48B_ADDRESS.  User must assume responsibility for any
      addressing workarounds.  Updated object2.offset field comment again to clarify
      NO_RELOC case (Chris).  checkpatch cleanup.
      
      v6: Trivial rebase on latest drm-intel-nightly
      
      v7: Catch attempts to pin above the max virtual address size and return
      EINVAL (Tvrtko). Decouple EXEC_OBJECT_SUPPORTS_48B_ADDRESS and
      EXEC_OBJECT_PINNED flags, user must pass both flags in any attempt to pin
      something at an offset above 4GB (Chris, Daniel Vetter).
      
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Akash Goel <akash.goel@intel.com>
      Cc: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
      Cc: Michal Winiarski <michal.winiarski@intel.com>
      Cc: Zou Nanhai <nanhai.zou@intel.com>
      Cc: Kristian Høgsberg <hoegsberg@gmail.com>
      Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
      Reviewed-by: NMichel Thierry <michel.thierry@intel.com>
      Acked-by: PDT
      Signed-off-by: NThomas Daniel <thomas.daniel@intel.com>
      Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
      Link: http://patchwork.freedesktop.org/patch/msgid/1449575707-20933-1-git-send-email-thomas.daniel@intel.com
      506a8e87
  15. 07 10月, 2015 1 次提交
  16. 20 3月, 2015 1 次提交
  17. 06 1月, 2015 2 次提交
  18. 19 9月, 2014 1 次提交
  19. 27 5月, 2014 1 次提交
    • C
      drm/i915: Prevent negative relocation deltas from wrapping · d23db88c
      Chris Wilson 提交于
      This is pure evil. Userspace, I'm looking at you SNA, repacks batch
      buffers on the fly after generation as they are being passed to the
      kernel for execution. These batches also contain self-referenced
      relocations as a single buffer encompasses the state commands, kernels,
      vertices and sampler. During generation the buffers are placed at known
      offsets within the full batch, and then the relocation deltas (as passed
      to the kernel) are tweaked as the batch is repacked into a smaller buffer.
      This means that userspace is passing negative relocations deltas, which
      subsequently wrap to large values if the batch is at a low address. The
      GPU hangs when it then tries to use the large value as a base for its
      address offsets, rather than wrapping back to the real value (as one
      would hope). As the GPU uses positive offsets from the base, we can
      treat the relocation address as the minimum address read by the GPU.
      For the upper bound, we trust that userspace will not read beyond the
      end of the buffer.
      
      So, how do we fix negative relocations from wrapping? We can either
      check that every relocation looks valid when we write it, and then
      position each object such that we prevent the offset wraparound, or we
      just special-case the self-referential behaviour of SNA and force all
      batches to be above 256k. Daniel prefers the latter approach.
      
      This fixes a GPU hang when it tries to use an address (relocation +
      offset) greater than the GTT size. The issue would occur quite easily
      with full-ppgtt as each fd gets its own VM space, so low offsets would
      often be handed out. However, with the rearrangement of the low GTT due
      to capturing the BIOS framebuffer, it is already affecting kernels 3.15
      onwards. I think only IVB+ is susceptible to this bug, but the workaround
      should only kick in rarely, so it seems sensible to always apply it.
      
      v3: Use a bias for batch buffers to prevent small negative delta relocations
      from wrapping.
      
      v4 from Daniel:
      - s/BIAS/BATCH_OFFSET_BIAS/
      - Extract eb_vma_misplaced/i915_vma_misplaced since the conditions
        were growing rather cumbersome.
      - Add a comment to eb_get_batch explaining why we do this.
      - Apply the batch offset bias everywhere but mention that we've only
        observed it on gen7 gpus.
      - Drop PIN_OFFSET_FIX for now, that slipped in from a feature patch.
      
      v5: Add static to eb_get_batch, spotted by 0-day tester.
      
      Testcase: igt/gem_bad_reloc
      Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=78533
      Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> (v3)
      Cc: stable@vger.kernel.org
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      d23db88c
  20. 31 3月, 2014 1 次提交
  21. 14 2月, 2014 1 次提交
    • D
      drm/i915: Consolidate binding parameters into flags · 1ec9e26d
      Daniel Vetter 提交于
      Anything more than just one bool parameter is just a pain to read,
      symbolic constants are much better.
      
      Split out from Chris' vma-binding rework patch.
      
      v2: Undo the behaviour change in object_pin that Chris spotted.
      
      v3: Split out misplaced hunk to handle set_cache_level errors,
      spotted by Jani.
      
      v4: Keep the current over-zealous binding logic in the execbuffer code
      working with a quick hack while the overall binding code gets shuffled
      around.
      
      v5: Reorder the PIN_ flags for more natural patch splitup.
      
      v6: Pull out the PIN_GLOBAL split-up again.
      
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Ben Widawsky <benjamin.widawsky@intel.com>
      Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      1ec9e26d
  22. 30 1月, 2014 2 次提交
  23. 22 1月, 2014 1 次提交
  24. 18 12月, 2013 1 次提交
  25. 10 12月, 2013 1 次提交
  26. 01 10月, 2013 1 次提交
  27. 13 9月, 2013 2 次提交
  28. 04 9月, 2013 1 次提交
    • D
      drm/i915: More vma fixups around unbind/destroy · b93dab6e
      Daniel Vetter 提交于
      The important bugfix here is that we must not unlink the vma when
      we keep it around as a placeholder for the execbuf code. Since then we
      won't find it again when execbuf gets interrupt and restarted and
      create a 2nd vma. And since the code as-is isn't fit yet to deal with
      more than one vma, hilarity ensues.
      
      Specifically the dma map/unmap of the sg table isn't adjusted for
      multiple vmas yet and will blow up like this:
      
      BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
      IP: [<ffffffffa008fb37>] i915_gem_gtt_finish_object+0x73/0xc8 [i915]
      PGD 56bb5067 PUD ad3dd067 PMD 0
      Oops: 0000 [#1] SMP
      Modules linked in: tcp_lp ppdev parport_pc lp parport ipv6 dm_mod dcdbas snd_hda_codec_hdmi pcspkr snd_hda_codec_realtek serio_raw i2c_i801 iTCO_wdt iTCO_vendor_support snd_hda_intel snd_hda_codec lpc_ich snd_hwdep mfd_core snd_pcm snd_page_alloc snd_timer snd soundcore acpi_cpufreq i915 video button drm_kms_helper drm mperf freq_table
      CPU: 1 PID: 16650 Comm: fbo-maxsize Not tainted 3.11.0-rc4_nightlytop_d93f59_debug_20130814_+ #6957
      Hardware name: Dell Inc. OptiPlex 9010/03JR84, BIOS A01 05/04/2012
      task: ffff8800563b3f00 ti: ffff88004bdf4000 task.ti: ffff88004bdf4000
      RIP: 0010:[<ffffffffa008fb37>]  [<ffffffffa008fb37>] i915_gem_gtt_finish_object+0x73/0xc8 [i915]
      RSP: 0018:ffff88004bdf5958  EFLAGS: 00010246
      RAX: 0000000000000000 RBX: ffff8801135e0000 RCX: ffff8800ad3bf8e0
      RDX: ffff8800ad3bf8e0 RSI: 0000000000000000 RDI: ffff8801007ee780
      RBP: ffff88004bdf5978 R08: ffff8800ad3bf8e0 R09: 0000000000000000
      R10: ffffffff86ca1810 R11: ffff880036a17101 R12: ffff8801007ee780
      R13: 0000000000018001 R14: ffff880118c4e000 R15: ffff8801007ee780
      FS:  00007f401a0ce740(0000) GS:ffff88011e280000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      CR2: 0000000000000008 CR3: 000000005635c000 CR4: 00000000001407e0
      Stack:
       ffff8801007ee780 ffff88005c253180 0000000000018000 ffff8801135e0000
       ffff88004bdf59a8 ffffffffa0088e55 0000000000000011 ffff8801007eec00
       0000000000018000 ffff880036a17101 ffff88004bdf5a08 ffffffffa0089026
      Call Trace:
       [<ffffffffa0088e55>] i915_vma_unbind+0xdf/0x1ab [i915]
       [<ffffffffa0089026>] __i915_gem_shrink+0x105/0x177 [i915]
       [<ffffffffa0089452>] i915_gem_object_get_pages_gtt+0x108/0x309 [i915]
       [<ffffffffa0085ba9>] i915_gem_object_get_pages+0x61/0x90 [i915]
       [<ffffffffa008f22b>] ? gen6_ppgtt_insert_entries+0x103/0x125 [i915]
       [<ffffffffa008a113>] i915_gem_object_pin+0x1fa/0x5df [i915]
       [<ffffffffa008cdfe>] i915_gem_execbuffer_reserve_object.isra.6+0x8d/0x1bc [i915]
       [<ffffffffa008d156>] i915_gem_execbuffer_reserve+0x229/0x367 [i915]
       [<ffffffffa008dbf6>] i915_gem_do_execbuffer.isra.12+0x4dc/0xf3a [i915]
       [<ffffffff810fc823>] ? might_fault+0x40/0x90
       [<ffffffffa008eb89>] i915_gem_execbuffer2+0x187/0x222 [i915]
       [<ffffffffa000971c>] drm_ioctl+0x308/0x442 [drm]
       [<ffffffffa008ea02>] ? i915_gem_execbuffer+0x3ae/0x3ae [i915]
       [<ffffffff817db156>] ? __do_page_fault+0x3dd/0x481
       [<ffffffff8112fdba>] vfs_ioctl+0x26/0x39
       [<ffffffff811306a2>] do_vfs_ioctl+0x40e/0x451
       [<ffffffff817deda7>] ? sysret_check+0x1b/0x56
       [<ffffffff8113073c>] SyS_ioctl+0x57/0x87
       [<ffffffff8135bbfe>] ? trace_hardirqs_on_thunk+0x3a/0x3f
       [<ffffffff817ded82>] system_call_fastpath+0x16/0x1b
      Code: 48 c7 c6 84 30 0e a0 31 c0 e8 d0 e9 f7 ff bf c6 a7 00 00 e8 07 af 2c e1 41 f6 84 24 03 01 00 00 10 75 44 49 8b 84 24 08 01 00 00 <8b> 50 08 48 8b 30 49 8b 86 b0 04 00 00 48 89 c7 48 81 c7 98 00
      RIP  [<ffffffffa008fb37>] i915_gem_gtt_finish_object+0x73/0xc8 [i915]
       RSP <ffff88004bdf5958>
      CR2: 0000000000000008
      
      As a consequence we need to change the "only one vma for now" check in
      vma_unbind - since vma_destroy isn't always called the obj->vma_list
      might not be empty. Instead check that the vma list is singular at the
      beginning of vma_unbind. This is also more symmetric with bind_to_vm.
      
      This fixes the igt/gem_evict_everything|alignment testcases.
      
      v2:
      - Add a paranoid WARN to mark_free in the eviction code to make sure
        we never try to evict a vma used by the execbuf code right now.
      - Move the check for a temporary execbuf vma into vma_destroy -
        otherwise the failure path cleanup in bind_to_vm will blow up.
      
      Our first attempting at fixing this was
      
      commit 1be81a2f2cfd8789a627401d470423358fba2d76
      Author: Chris Wilson <chris@chris-wilson.co.uk>
      Date:   Tue Aug 20 12:56:40 2013 +0100
      
          drm/i915: Don't destroy the vma placeholder during execbuffer reservation
      
      Squash with this when merging!
      
      v3: Improvements suggested in Chris' review:
      - Move the WARN_ON in vma_destroy that checks for vmas with an drm_mm
        allocation before the early return.
      - Bail out if we hit the WARN in mark_free to hopefully make the
        kernel survive for long enough to capture it.
      
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Cc: Ben Widawsky <ben@bwidawsk.net>
      Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=68298
      Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=68171
      Tested-by: lu hua <huax.lu@intel.com> (v2)
      Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      b93dab6e
  29. 23 8月, 2013 1 次提交
    • B
      drm/i915/vma: Correct use after free in eviction · 8637b407
      Ben Widawsky 提交于
      The vma will [possibly] be destroyed during unbind in eviction.
      Immediately after this, we try to delete the list entry.
      
      Chris and Ville did the debug on this before I woke up, I just get to
      take credit for the fix :p
      
      For future reference the Oops that Mika reported:
      
      [  403.472448] BUG: unable to handle kernel paging request at 6b6b6b6b
      [  403.472473] IP: [<c12c1500>] __list_del_entry+0x20/0xe0
      [  403.472514] *pdpt = 000000002e89c001 *pde = 0000000000000000
      [  403.472556] Oops: 0000 [#1] SMP
      [  403.472582] Modules linked in: mxm_wmi snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_seq_midi snd_rawmidi psmouse snd_seq_midi_event snd_seq serio_raw snd_timer snd_seq_device snd soundcore snd_page_alloc wmi bnep rfcomm bluetooth mac_hid parport_pc ppdev lp parport usbhid dm_crypt firewire_ohci firewire_core crc_itu_t i915 drm_kms_helper e1000e ptp drm i2c_algo_bit pps_core xhci_hcd video
      [  403.472895] CPU: 2 PID: 1940 Comm: Xorg Not tainted 3.11.0-rc2+ #827
      [  403.472938] Hardware name:                  /DZ77BH-55K, BIOS BHZ7710H.86A.0070.2012.0416.2117 04/16/2012
      [  403.473002] task: ec866c00 ti: ee6a2000 task.ti: ee6a2000
      [  403.473039] EIP: 0060:[<c12c1500>] EFLAGS: 00013202 CPU: 2
      [  403.473078] EIP is at __list_del_entry+0x20/0xe0
      [  403.473109] EAX: f016d9bc EBX: f016d9bc ECX: 6b6b6b6b EDX: 6b6b6b6b
      [  403.473151] ESI: 00000000 EDI: ee6a3c90 EBP: ee6a3c60 ESP: ee6a3c48
      [  403.473193]  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
      [  403.473230] CR0: 80050033 CR2: 6b6b6b6b CR3: 2ec43000 CR4: 001407f0
      [  403.473271] Stack:
      [  403.473285]  f63b2ff0 f61f98c0 f61f8000 f016d9bc 00000000 f016d9bc ee6a3cac f8519a4a
      [  403.473347]  00000000 00000000 10000000 f61f8000 0100a000 10000000 00000001 008ca000
      [  403.473410]  f64ee840 f61f98c0 f016d9bc f016dcec ee6a3c98 ee6a3c98 f61f98c0 dcc58f00
      [  403.473472] Call Trace:
      [  403.473509]  [<f8519a4a>] i915_gem_evict_something+0x17a/0x2d0 [i915]
      [  403.473567]  [<f8516ed1>] i915_gem_object_pin+0x271/0x660 [i915]
      [  403.473622]  [<f851c740>] ? i915_ggtt_clear_range+0x20/0x20 [i915]
      [  403.473676]  [<f8517afa>] i915_gem_object_pin_to_display_plane+0xda/0x190 [i915]
      [  403.473742]  [<f852d9fa>] intel_pin_and_fence_fb_obj+0xba/0x140 [i915]
      [  403.473800]  [<f852db40>] intel_gen7_queue_flip+0x30/0x1c0 [i915]
      [  403.473856]  [<f85337b0>] intel_crtc_page_flip+0x1a0/0x320 [i915]
      [  403.473911]  [<f847b549>] ? drm_framebuffer_reference+0x39/0x80 [drm]
      [  403.473965]  [<f847f9fb>] drm_mode_page_flip_ioctl+0x28b/0x320 [drm]
      [  403.474018]  [<f846fec8>] drm_ioctl+0x4b8/0x560 [drm]
      [  403.474064]  [<f847f770>] ? drm_mode_gamma_get_ioctl+0xd0/0xd0 [drm]
      [  403.474113]  [<c1140f8a>] ? do_sync_read+0x6a/0xa0
      [  403.474154]  [<f846fa10>] ? drm_copy_field+0x80/0x80 [drm]
      [  403.474193]  [<c115134c>] do_vfs_ioctl+0x7c/0x5b0
      [  403.474228]  [<c1141d2f>] ? vfs_read+0xef/0x160
      [  403.474263]  [<c108dcbb>] ? ktime_get_ts+0x4b/0x120
      [  403.474298]  [<c1151917>] SyS_ioctl+0x97/0xa0
      [  403.474330]  [<c1590bc1>] sysenter_do_call+0x12/0x22
      [  403.474364] Code: 55 f4 8b 45 f8 e9 75 ff ff ff 90 55 89 e5 53 83 ec 14 8b 08 8b 50 04 81 f9 00 01 10 00 74 24 81 fa 00 02 20 00 0f 84 8e 00 00 00 <8b> 1a 39 d8 75 62 8b 59 04 39 d8 75 35 89 51 04 89 0a 83 c4 14
      [  403.474566] EIP: [<c12c1500>] __list_del_entry+0x20/0xe0 SS:ESP 0068:ee6a3c48
      [  403.476513] CR2: 000000006b6b6b6b
      
      v2: Missed the drm_object_unreference use after free (Ville)
      Daniel Vetter <daniel@ffwll.ch> writes:
      Reported-by: NMika Kuoppala <mika.kuoppala@intel.com>
      Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
      Cc: Chris Wilson <chris@chris-wilson.co.uk>
      Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
      Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
      [danvet: Add the Oops from Mika to the commit message.]
      Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
      8637b407