Dual monitor with amd 5700 causes system to,hang at startup (fwd from bugzilla) #forregzbot

[Thorsten Leemhuis <regressions@leemhuis.info>]

Lo! There is a regression dealt with in bugzilla I'd like to add to the
tracking:

#regzbot introduced: v5.15.8..v5.15.13
#regzbot link: https://bugzilla.kernel.org/show_bug.cgi?id=215511
#regzbot from: Jose Mestre <pmestre@gmail.com>
#regzbot title: drm: amdgpu: Dual monitor with amd 5700 causes system to
hang at startup.

Note: also present in 5.16.1

Quote:

> Hello, system mostly crashes (sometimes in different ways) when i
> start with more than one monitor attached.
> 
> If i switch off one monitor then system boots correctly (i don't need
> to detach the displayport cable, just to switch off the monitor).
> 
> 
> When both monitors are connected, most of the times it just crashes
> as the attached log, sometimes it boots but screen is flickering and
> with artifacts.
> 
> This happened with kernel 5.10 and 5.11, it was fixed i don't
> remember exactly when, and is happening again. For me it worked with
> kernel 5.15.8 and failed with 5.15.13. It is still failing with
> 5.16.1.
> 
> Kind regards and many thanks for your work in the most crucial
> open-source project.

Ciao, Thorsten

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