[GLK] all tests - dmesg-warn / dmesg-fail/fail - *ERROR* CPU pipe [AB] FIFO underrun

Submitted by Tomi Sarvela @tsa

Assigned to Intel GFX Bugs mailing list

Link to original bug (#106538)

Description

FIFO underruns made an appearance on Gemini Lake NUCs. Examples of tests it hits:

https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_4182/shard-glk4/igt@kms_cursor_legacy@cursorb-vs-flipb-toggle.html

https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_4182/shard-glk4/igt@kms_cursor_legacy@flip-vs-cursor-crc-atomic.html

https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_4182/shard-glk4/igt@kms_busy@extended-pageflip-modeset-hang-oldfb-render-b.html

This might be residual issues from 4.17-rc5 pull, and happened only on one run on host, so we'll follow if it happens again.

Blocking

• Bug 105980