[vfio-users] vga passthrough works but no grub screen for linux guest

[Christoph Willing]

On 30/6/19 11:07 pm, Bronek Kozicki wrote:
> On Sun, 30 Jun 2019, at 1:41 PM, Christoph Willing wrote:
>> I have vga passthrough working with a linux guest running in qemu-3.1.0
>> on a host with two Nvidia Quadro K600 cards and the nvidia binary driver
>> 430.26 installed. A dedicated keyboard & mouse is also passed through
>> successfully so, in general, I'm pretty happy with the setup but ...
>>
>> when I use OVMF and run the guest without passthrough (just a regular
>> qemu vm running on the host display) I see a grub screen to select a
>> particular kernel, followed by the usual console output during bootup
>> before X starts. However, when running with passthrough enabled, the
>> guest vm's monitor (Samsung U28D590) shows nothing until X starts -
>> there is no grub screen and no console output.
>>
>> Before I had the nvidia binary driver installed in the guest, I had some
>> console output while booting but still no grub screen.
>>
>> Is there some way I can see everything including the grub screen, or is
>> it normal not to see that in the guest?
> 
> It is normal on my Quadro M5000 - these cards are not supported as primary display with passthrough. This might be something to do with ROM, but I was not successful trying to investigate further. To compensate for this all my virtual machines have serial console, so I can do "virsh console"
> 
> 
> B.
> 

Thanks for the confirmation Bronek - it's good to know I'm not the only
one seeing this. I'll give it a try with serial console.

chris