Re: black screen troubles trying to boot with Xen Hypervisor grub option

[Jamie Campbell <jamie@xxxxxxxx>]

Hello Elge,

I've attached the grub config prior to the xen metapackage and also the 
grub config after xen metapackage install.  The pre-xen config might not 
be relevant but I'm attaching it in case the diff does turn out to have 
relevance.  Comments scrubbed from both.
You mention serial console but in my case the computer has no physical 
serial port nor the virtual SOL approach.
While digging in to what's going on I also noticed that the base 
hypervisor entry has a conditional branch checking $grub_platform so I 
added an echo to figure out which branch it's picking, and it turns out 
that in my case $grub_platform isn't "pc" and isn't empty but rather is 
"efi" so it does the "no-real-mode edd=off" options.  When I read about 
them in the documentation says that no-real-mode should only be used for 
debugging because it prevents vga from working, and I got excited 
because I thought "and therefore black screen!" but when I force it to 
use no options, like the "pc" branch does, it still gets black screen.
-Jamie

On 2023-07-08 11:08 p.m., Pierre-Philipp Braun wrote:
> > (XEN) 3... 2... 1...
> Hello Jamie, so question is, what does your GRUB config look like 
> (without the comments please), so we can see if you are having serial 
> console specifics as for booting the linux kernel and userland.
> There are mainly three steps in booting a dom0:
>
> 1. xen micro-kernel
> 2. linux kernel (and eventually initramfs)
> 3. userland and getty
>
> all three can have different output.  Here's a few hints on how to 
> tackle grub.conf manually.
> https://pub.nethence.com/booting/grub
>
> -elge

Attachment: grub-before-xen--nocomments.cfg
Description: Text document

Attachment: grub-after-metapackage-xen-system-amd64--nocomments.cfg
Description: Text document