>>> Do you see the Xen boot messages on the screen ?
>>>
>>
>> No, the screen turns black right after the message:
>>
>> ```
>> Loading /netbsd-XEN3_DOM0.gz.../
Matthias there were two implicit components in the question. XEN boot
msg and dom0's kernel boot msg.
> this means that Xen doesn't know how to deal with the video adapter.
>
> I'm not sure Xen fully supports UEFI at this time (at last in Xen 4.13)
Last time I considered it, about one or two years ago, EFI and XEN was
still looking like a nightmare. I would recommend to switch to
legacy/CSM/BIOS mode if the machine supports it. It will make XEN
booting much easier. We can sure help if you want to go in that direction.
This issue of blank booting screen was common and happens on CentOS/RHEL
and Debian systems also. I guess it's indeed because it was sometimes
trying to spit on tty0 by default instead of vga.
I notice however that your `console=pc` setting which applies to XEN
micro-kernel may be wrong:try console=vga instead *1?
As for dom0's kernel boot msgs, there are surely ways to tune that also
specifically for NetBSD *2. Try to force it over there: maybe `consdev
pc`?
*1 https://xenbits.xen.org/docs/unstable/misc/xen-command-line.html#console
*2 https://man.netbsd.org/NetBSD-8.0/x86/boot.8
https://man.netbsd.org/NetBSD-8.0/x86/boot_console.8