From mboxrd@z Thu Jan  1 00:00:00 1970
From: "pelzflorian (Florian Pelz)" <pelzflorian@pelzflorian.de>
Subject: bug#40538: installer: Support uvesafb to install on machines without
 KMS.
Date: Tue, 14 Apr 2020 10:16:52 +0200
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To: Mathieu Othacehe <m.othacehe@gmail.com>
Cc: 40538@debbugs.gnu.org

On Tue, Apr 14, 2020 at 09:24:52AM +0200, Mathieu Othacehe wrote:
> 
> Hello Florian,
> 
> > Please try adding nomodeset to the kernel parameters.  I hope this
> > makes the Intel machine work fine.
> 
> Yes it works fine with nomodeset! Do you think we can do something about
> it, besides adding a few lines in the documentation to warn that old
> hardware may require this option?
> 
> Thanks,
> 
> Mathieu

That is good to hear!  The options I know of are:

1) Make the loading of the uvesafb kernel module by the installer
conditional.  For your GPU, don’t load uvesafb, if before it worked
without.

2) Add modprobe.blacklist=i915 to the default kernel parameters (or
whatever the kernel module for this GPU is), so this kind of GPU
always only uses uvesafb.

3) Add nomodeset to the default kernel parameters for the installer,
so all GPUs always use uvesafb.

I do not know if uvesafb works on all display technologies though.

uvesafb certainly is not supported on ARM (though maybe it works; the
README of uvesafb’s helper program v86d just says it is not supported).

Regards,
Florian