Subject: Re: bug#76554: Laptop screen blank after kexec reboot

From: Simon Streit <[email-masked]>
Date: Tue, 06 May 2025 07:56:27 +0200

Ludovic Courtès <[email-masked]> writes:

> Simon Streit <[email-masked]> writes:
>
>> Maxim Cournoyer <[email-masked]> writes:
>>
>>> So just to make sure I got that right, it works correctly on Debian
>>> but incorrectly (black screen) on Guix System on the *same* hardware?
>>
>> correct.
>
> Actually we “just” need to set screen brightness at activation-time:
>
>   https://issues.guix.gnu.org/76554#5

Unfortunately it is not just the brightness at its lowest setting.  I
have no video signal on my machine to begin with.  If that would be the
case, then the back light of the screen is usually visible while powered
on.  Despite that, once the disk is unlocked and the boot process
completed the screen does activate at the lowest brightness level.

This might mean that on some machines the screen does go on, while on
others it doesn't.  Maybe there are others that can report on this
issue?

I currently don't have a different type of machine to test this
scenario.

Kind regards

-- 
Simon