[SOLVED] Can't passthrough 980 TI to Win 10 VM

[Squeeth]

I've been trying to configure a Windows 10 VM for the last two days to utilize my 980 TI, but I can not for the life of me get it to passthrough to the VM properly.

I've followed every video SpaceInvader One has out there about GPU passthrough, followed multiple suggestions on here about starting with VNC and trying to install drivers, letting that fail, shutdown, add GPU, and finish driver install, SeaBios and OVMF, Q35 and i440fx...but all to no successful outcomes.

I've done the XML edit for multifunction, stubbing the card, using a no VBIOS dump, untouched dump, modded dump per SIOs tutorials...I'm just at a loss here now. Wondering if anyone has a helping hand to try and help resolve this, or a current config similar with their setup that can point me in the right direction.

Thanks in advance!

ethan-unraid-diagnostics-20220116-2245.zip

Edited January 18, 2022 by Squeeth

[ghost82]

I assume the vm is 'Streaming VM'?

Set it multifunction:

    <hostdev mode='subsystem' type='pci' managed='yes'>
      <driver name='vfio'/>
      <source>
        <address domain='0x0000' bus='0x03' slot='0x00' function='0x0'/>
      </source>
      <rom file='/mnt/user/isos/NVIDA 980TI dump.rom'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0' multifunction='on'/>
    </hostdev>
    <hostdev mode='subsystem' type='pci' managed='yes'>
      <driver name='vfio'/>
      <source>
        <address domain='0x0000' bus='0x03' slot='0x00' function='0x1'/>
      </source>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x1'/>
    </hostdev>

 

Dump your own vbios.

 

Jan 16 21:15:11 ETHAN-UNRAID kernel: pci 0000:03:00.0: can't claim BAR 6 [mem 0xfff80000-0xffffffff pref]: no compatible bridge window

Probably in use by efifb

 

--> modify your syslinux config and add in the append line:

video=efifb:off

 

[Squeeth]

20 minutes ago, ghost82 said:

I assume the vm is 'Streaming VM'?

Set it multifunction:

    <hostdev mode='subsystem' type='pci' managed='yes'>
      <driver name='vfio'/>
      <source>
        <address domain='0x0000' bus='0x03' slot='0x00' function='0x0'/>
      </source>
      <rom file='/mnt/user/isos/NVIDA 980TI dump.rom'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0' multifunction='on'/>
    </hostdev>
    <hostdev mode='subsystem' type='pci' managed='yes'>
      <driver name='vfio'/>
      <source>
        <address domain='0x0000' bus='0x03' slot='0x00' function='0x1'/>
      </source>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x1'/>
    </hostdev>

 

Dump your own vbios.

 

Jan 16 21:15:11 ETHAN-UNRAID kernel: pci 0000:03:00.0: can't claim BAR 6 [mem 0xfff80000-0xffffffff pref]: no compatible bridge window

Probably in use by efifb

 

--> modify your syslinux config and add in the append line:

video=efifb:off

 

Thanks Ghost! Yes it is the Streaming VM and I'm excited to give it another shot. How you see everything is how I left it after my 6th or 7th attempt, hence why multifunction was off and my own vbios wasn't dumped.

 

Adding that into my syslinux config was something I didn't do, so hopefully that was the missing piece of the puzzle!

[Squeeth]

Moving to solved. Couldn't dump my cards VBios on my own, tried the old school and the SIO script...no joy.

Did add the video=efifb:off to the append line in syslinux, and switched my boards BIOS to boot Legacy. 980 TI successfully started working in passthrough after that.

[ghost82]

4 hours ago, Squeeth said:

and switched my boards BIOS to boot Legacy

With this change I think that video=efifb:off is not needed because with legacy bios boot efifb won't be used.