Freeze during reboot of Windows 10

[frevan]

Hello,

 

I configured some virtual machines with Windows 10 and GPU passthrough and they work very well so far. There's only one problem at this point, but it's a bit annoying: when I reboot Windows, it shuts down, I see the POST screen and then I get a black screen with just a text cursor (which doesn't blink) on it. I then have to force stop the VM and start it again, which works fine.

 

Has anyone seen this problem before? Is there a solution? I did search the forum, but I didn't find anything so far.

 

Some information about the system:

- Gigabyte motherboard with Z170 chipset

- Skylake Pentium cpu (cheapest I could find, because I'm just testing at this point)

- tried GeForce GT610, Radeon R9 270X and Quadro M2000 cards

 

I tried with and without breaking up the IOMMU groups and with just one and two cards in the system.

[frevan]

I forgot to mention I'm using the latest 6.2 beta.

[saarg]

What happens if you safely remove the graphics card before rebooting?

It's done the same way as you safely remove a USB drive.

[frevan]

I didn't know that was possible. I'm not sure what happens in this case, as I don't see anything on the screen.

 

This is what I do and what (seems to) happen:

1. I initiate a delayed reboot with the command "shutdown /r /t 10" (and click away the warning message that appears)

2. I safely remove the graphics card (but not the corresponding soundcard, if that matters)

3. the screen goes black

4. the computer's hdd has some activity for a bit, so I assume it's rebooting

5. the screen never comes back on

[frevan]

I tried with Remote Desktop now and it looks like the computer crashes when I remove the GPU (the RDP connection is lost and can't be restored).

[frevan]

It seems to reboot fine with SeaBIOS instead of OVMF. I'll have to try it a bit more to be certain, but it looks good so far.

 

Does anyone know if this would be a bug in OVMF or something I did wrong?

[bungee91]

It seems to reboot fine with SeaBIOS instead of OVMF. I'll have to try it a bit more to be certain, but it looks good so far.

 

Does anyone know if this would be a bug in OVMF or something I did wrong?

 

There have been reports of users with certain hardware having better results with OVMF or SeaBios, so just choose the one that works best for you if it makes a difference.

SeaBIOS will unfortunately kill any console VGA output if you happen to rely on this for your server.

Performance wise they should be identical once VGA arbitration is completed, and you are within the OS.

 

[bigjme]

I agree with bungee, I have 1 machine that will boot in seabios but not in ovmf. I also have another vm that will run under both but performs better using ovmf

 

It's a case of try and see which is better. Luckily as your on the latest beta you can load up the system logs within the unraid screen and use those while the seabios runs.

 

I recommend even if the output is not connected that you open the unraid log full screen in the Linux environment, it has saved me a few times with system locks etc.

[frevan]

Thanks for the replies. The loss of the console doesn't matter to me, I'll just run a couple of Windows VMs.

[joohn]

I can confirm that switching from OVMF to SeaBios fixed the same problem for me. I didn't use GPU pass through at all, just regular Windows 10 installation. Problem was the same - not blinking cursor on a black screen, just before restart. After force stop, machine started ok.

 

I have also tried switching from fx440 to Q35, but no luck. SeaBios did the trick.