Re: Fwd: 6.1.23: 0fc6fea41c71 breaks GPD Pocket 3 modeset

["Linux regression tracking (Thorsten Leemhuis)" <regressions@leemhuis.info>]

[CCing the intel drm maintainers and the lists; also CCing the
regression list, as it should be in the loop for regressions:
https://docs.kernel.org/admin-guide/reporting-regressions.html]

[TLDR: I'm adding this report to the list of tracked Linux kernel
regressions; the text you find below is based on a few templates
paragraphs you might have encountered already in similar form.
See link in footer if these mails annoy you.]

On 29.04.23 23:38, Kurt Garloff wrote:
> Hi Ville,
> 
> (sorry for the resend, had forgotten that LKML still believes
> that multipart with an HTML version is evil)
> 
> While
> 0fc6fea41c71 drm/i915: Disable DC states for all commits
> (cherry picked from commit 41b4c7fe72b6105a4b49395eea9aa40cef94288d)

/me wonders if 6.3 is affected as well, but will treat it as stable
specific regression for now

> does look correct to me, it does break modesetting on the
> GPD Pocket 3, a i7-1195G7 laptop. I run the kernel with
> fbcon=rotate:1 video=DSI-1:panel_orientation=right_side_up \
>   mem_sleep_default=s2idle
> No special i915 parameters.
> 
> Hardware is described here:
> https://wiki.archlinux.org/title/GPD_Pocket_3
> 
> I disected this patch which was merged (backported) for 6.1.23.
> I currently run 6.1.26 with it reverted and life is good.
> 
> Without reverting it, when fbcon is switched to show the splash
> screen (GPD logo with Ubuntu added in on working kernels), the
> screen remains black (backlight on, but nothing displayed) and
> nothing happens any more. It looks like something more serious
> than just blackness, as SysRq or Ctrl-Alt-Del don't do anything.
> Deadlocking?

Thanks for the report. To be sure the issue doesn't fall through the
cracks unnoticed, I'm adding it to regzbot, the Linux kernel regression
tracking bot:

#regzbot ^introduced 0fc6fea41c71
#regzbot title drm: i915: GPD Pocket 3 modeset broken
#regzbot ignore-activity

This isn't a regression? This issue or a fix for it are already
discussed somewhere else? It was fixed already? You want to clarify when
the regression started to happen? Or point out I got the title or
something else totally wrong? Then just reply and tell me -- ideally
while also telling regzbot about it, as explained by the page listed in
the footer of this mail.

Developers: When fixing the issue, remember to add 'Link:' tags pointing
to the report (the parent of this mail). See page linked in footer for
details.

Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
--
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