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

[Bronek Kozicki]

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.

-- 
  Bronek Kozicki
  brok at spamcop.net