Also seen on KBL:

https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_65/fi-kbl-7560u/igt@kms_plane@pixel-format-pipe-b-planes.html

Also seen on ICL: https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_94/fi-icl-u/igt@kms_plane@pixel-format-pipe-b-planes.html

https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_115/fi-skl-caroline/igt@kms_plane@pixel-format-pipe-b-planes.html

<3> [306.918597] [drm:drm_crtc_add_crc_entry] *ERROR* Overflow of CRC buffer, userspace reads too slow.

Not seen on ICL lately?

(In reply to Jani Saarinen from comment #4)
> Not seen on ICL lately?

Last seen in https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_117/fi-icl-u/igt@kms_plane@pixel-format-pipe-a-planes.html, after being seen every single drmtip run after drmtip_95 (introduction of ICL).

I guess this is sufficient to say that ICL is fixed.

If this error is not seen regularly, maybe we could pump up a bit the size of a ringbuffer. Now, we have DRM_CRC_ENTRIES_NR defined as 128, so maybe we could increase it to 256?

(In reply to Mika Kahola from comment #6)
> If this error is not seen regularly, maybe we could pump up a bit the size
> of a ringbuffer. Now, we have DRM_CRC_ENTRIES_NR defined as 128, so maybe we
> could increase it to 256?

Are the CRCs per pipe or global? If it is per-pipe, then 128 CRCs @ 60 Hz is more than 2 seconds of not reading the crc... I would think that this ought to be sufficient and if it is not, we really need to look into why we have such latency in the userspace, don't you think? :o

Also seen on BSW
https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_157/fi-bsw-n3050/igt@kms_plane@pixel-format-pipe-c-planes-source-clamping.html

https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_158/fi-bsw-n3050/igt@kms_plane@pixel-format-pipe-c-planes-source-clamping.html

(In reply to Martin Peres from comment #7)
> (In reply to Mika Kahola from comment #6)
> > If this error is not seen regularly, maybe we could pump up a bit the size
> > of a ringbuffer. Now, we have DRM_CRC_ENTRIES_NR defined as 128, so maybe we
> > could increase it to 256?
> 
> Are the CRCs per pipe or global? If it is per-pipe, then 128 CRCs @ 60 Hz is
> more than 2 seconds of not reading the crc... I would think that this ought
> to be sufficient and if it is not, we really need to look into why we have
> such latency in the userspace, don't you think? :o

The latency would be from the combination of things; IGT by default is compiled with no optimizations switched on, used framebuffer sizes are quite big (3840x2160 for example), and because lack of YUV support in cairo there's in IGT conversions back'n'forth RGB<->YUV..all this combined probably can build up to 2s wait.

One could try putting some "#pragma GCC optimize ("O3")" around those conversion functions "static void convert_XXX_to_XXX(struct fb_convert *cvt)" found in igt_fb.c, though I think this is just painting over the problem.

Other solution would be starting/stopping crc when crc is really needed but it would slow down tests in kms_plane even more.

https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_5313/shard-iclb7/igt@kms_plane@pixel-format-pipe-a-planes-source-clamping.html

Starting subtest: pixel-format-pipe-A-planes-source-clamping
(kms_plane:8972) igt_debugfs-CRITICAL: Test assertion failure function igt_assert_crc_equal, file ../lib/igt_debugfs.c:419:
(kms_plane:8972) igt_debugfs-CRITICAL: Failed assertion: !mismatch
Subtest pixel-format-pipe-A-planes-source-clamping failed.

<3> [1494.718728] [drm:drm_crtc_add_crc_entry] *ERROR* Overflow of CRC buffer, userspace reads too slow.
<3> [1519.117242] [drm:drm_crtc_add_crc_entry] *ERROR* Overflow of CRC buffer, userspace reads too slow.
<3> [1542.905928] [drm:drm_crtc_add_crc_entry] *ERROR* Overflow of CRC buffer, userspace reads too slow.

A CI Bug Log filter associated to this bug has been updated:

{- BSW SKL KBL GLK CNL ICL: igt@kms_plane@pixel-format-pipe-[abc]-planes.* - *ERROR* Overflow of CRC buffer, userspace reads too slow. -}
{+ BSW SKL KBL GLK CNL ICL: igt@kms_plane@pixel-format-pipe-[abc]-planes.*|kms_rotation_crc@primary-* - *ERROR* Overflow of CRC buffer, userspace reads too slow. +}

New failures caught by the filter:

* https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_221/fi-icl-u3/igt@kms_rotation_crc@primary-x-tiled-reflect-x-0.html
* https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_221/fi-icl-u3/igt@kms_rotation_crc@primary-yf-tiled-reflect-x-0.html
* https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_224/fi-icl-u3/igt@kms_rotation_crc@primary-y-tiled-reflect-x-270.html

https://patchwork.freedesktop.org/series/54364/

A CI Bug Log filter associated to this bug has been updated:

{- BSW SKL KBL GLK CNL ICL: igt@kms_plane@pixel-format-pipe-[abc]-planes.*|kms_rotation_crc@primary-* - *ERROR* Overflow of CRC buffer, userspace reads too slow. -}
{+ BSW SKL KBL GLK CNL ICL: igt@kms_plane@pixel-format-pipe-[abc]-planes.*|kms_rotation_crc@-* - *ERROR* Overflow of CRC buffer, userspace reads too slow. +}

New failures caught by the filter:

* https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_232/fi-icl-u3/igt@kms_rotation_crc@sprite-rotation-90.html

commit b25e06d6ddf2e42044cd9c93b613cbc7339a8c33
Author: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Date:   Thu Mar 7 12:54:11 2019 +0100

    tests/kms_plane: Reduce execution time by reducing source size and performing upscaling.

(In reply to Maarten Lankhorst from comment #14)
> commit b25e06d6ddf2e42044cd9c93b613cbc7339a8c33
> Author: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> Date:   Thu Mar 7 12:54:11 2019 +0100
> 
>     tests/kms_plane: Reduce execution time by reducing source size and
> performing upscaling.

Thanks! I am still re-opening because kms_rotation_crc has not been fixed yet.

On ICL we are updating newer BIOS that should help here. To be seen...

Not seen on ICL-U2/U3 lately that already has new BIOS

It's an IGT issue as we use inefficient ways of generating FBs which take too much time, while CRC machinery is up making us overflow the CRC buffer.

The impact on users is negligible - this is just dmesg warn telling our tests that we are too slow on readout, other than that the test is passing.

Requires test improvements.

The CI Bug Log issue associated to this bug has been updated.

### New filters associated

* ICL: igt@kms_rotation_crc@primary-rotation-90 - crash - *ERROR* Overflow of CRC buffer, userspace reads too slow.
  - https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_277/fi-icl-y/igt@kms_rotation_crc@primary-rotation-90.html

Also on ICL-Y BIOS update made to DMI: Intel Corporation Ice Lake Client Platform/IceLake Y LPDDR4x T4 RVP TLC, BIOS ICLSFWR1.R00.3162.A00.1904162000 04/16/2019

A CI Bug Log filter associated to this bug has been updated:

{- BSW SKL KBL GLK CNL ICL: igt@kms_plane@pixel-format-pipe-[abc]-planes.*|kms_rotation_crc@-* - *ERROR* Overflow of CRC buffer, userspace reads too slow. -}
{+ BSW APL SKL KBL GLK CNL ICL: igt@kms_plane@pixel-format-pipe-[abc]-planes.*|kms_rotation_crc@-*|igt@kms_plane_multiple@* - *ERROR* Overflow of CRC buffer, userspace reads too slow. +}

New failures caught by the filter:

  * https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_289/fi-apl-guc/igt@kms_plane_multiple@atomic-pipe-c-tiling-yf.html

A CI Bug Log filter associated to this bug has been updated:

{- BSW APL SKL KBL GLK CNL ICL: igt@kms_plane@pixel-format-pipe-[abc]-planes.*|kms_rotation_crc@-*|igt@kms_plane_multiple@* - *ERROR* Overflow of CRC buffer, userspace reads too slow. -}
{+ BYT BSW APL SKL KBL GLK CNL ICL: igt@kms_plane@pixel-format-pipe-[abc]-planes.*|kms_rotation_crc@-*|igt@kms_plane_multiple@* - *ERROR* Overflow of CRC buffer, userspace reads too slow. +}

New failures caught by the filter:

  * https://intel-gfx-ci.01.org/tree/drm-tip/drmtip_339/fi-byt-n2820/igt@kms_plane@pixel-format-pipe-a-planes-source-clamping.html

A CI Bug Log filter associated to this bug has been updated:

{- BYT BSW APL SKL KBL GLK CNL ICL: igt@kms_plane@pixel-format-pipe-[abc]-planes.*|kms_rotation_crc@-*|igt@kms_plane_multiple@* - *ERROR* Overflow of CRC buffer, userspace reads too slow. -}
{+ BYT BSW APL SKL KBL GLK CNL ICL TGL: igt@kms_*- *ERROR* Overflow of CRC buffer, userspace reads too slow. +}

New failures caught by the filter:

  * https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7104/re-tgl-u/igt@kms_plane_lowres@pipe-a-tiling-y.html

-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/drm/igt-gpu-tools/issues/6.

A CI Bug Log filter associated to this bug has been updated:

{- BYT BSW APL SKL KBL GLK CNL ICL TGL: igt@kms_*- *ERROR* Overflow of CRC buffer, userspace reads too slow. -}
{+ BYT BSW APL SKL KBL GLK CNL ICL TGL: igt@kms_*- *ERROR* Overflow of CRC buffer, userspace reads too slow. +}

New failures caught by the filter:

  * https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7299/shard-apl6/igt@kms_cursor_legacy@flip-vs-cursor-busy-crc-legacy.html

A CI Bug Log filter associated to this bug has been updated:

{- BYT BSW APL SKL KBL GLK CNL ICL TGL: igt@kms_*- *ERROR* Overflow of CRC buffer, userspace reads too slow. -}
{+ BYT BSW APL SKL KBL GLK CNL ICL TGL: igt@kms_*- *ERROR* Overflow of CRC buffer, userspace reads too slow. +}

New failures caught by the filter:

  * https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_7325/re-tgl-y/igt@kms_plane_multiple@atomic-pipe-d-tiling-y.html