[Intel-gfx] ✗ Fi.CI.BAT: failure for drm/i915: Improve DP link training further (rev4)

[Ville Syrjälä]

On Tue, Oct 05, 2021 at 12:49:53PM -0000, Patchwork wrote:
> == Series Details ==
> 
> Series: drm/i915: Improve DP link training further (rev4)
> URL   : https://patchwork.freedesktop.org/series/95405/
> State : failure
> 
> == Summary ==
> 
> CI Bug Log - changes from CI_DRM_10683 -> Patchwork_21247
> ====================================================
> 
> Summary
> -------
> 
>   **FAILURE**
> 
>   Serious unknown changes coming with Patchwork_21247 absolutely need to be
>   verified manually.
>   
>   If you think the reported changes have nothing to do with the changes
>   introduced in Patchwork_21247, please notify your bug team to allow them
>   to document this new failure mode, which will reduce false positives in CI.
> 
>   External URL: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_21247/index.html
> 
> Possible new issues
> -------------------
> 
>   Here are the unknown changes that may have been introduced in Patchwork_21247:
> 
> ### IGT changes ###
> 
> #### Possible regressions ####
> 
>   * igt at core_hotunplug@unbind-rebind:
>     - fi-tgl-u2:          NOTRUN -> [INCOMPLETE][1]
>    [1]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_21247/fi-tgl-u2/igt@core_hotunplug@unbind-rebind.html

That looks like a straight up race during unbind. We turn off
interrupts first, only then we cancel the hpd stuff (including the
modeset_retry work) which presuambly was already running and told
fb_helper that stuff happened, then the fb_helper proceeds to do
a modeset while interrupts are already off and we're in the middle
of tearing down the driver, and all hell breaks loose as a result.

Unrelated to these patches, I *think*. I'll hit retest anyway to
make sure.

-- 
Ville Syrjälä
Intel