GPU Passthrough to Windows 10 is fine, but Linux pins first core at 100% and does not boot

[reporrted]

I have a Windows 10 guest up and running just fine. I want to add a Debian guest. It works OK with VNC graphics but as soon as I attach a GPU, Sound or USB devices it pins at 100% usage and does not boot. I feel like I am overlooking something simple here, or I have broken something in order to make the Windows 10 VM work that then in turn does not work with other VM's.

Can someone help direct me to where I should be looking to resolve this?

Thank you.

 

 

tower.lan-diagnostics-20220202-2132.zip

[reporrted]

Small update, but not fixed. It's the sound chipset I believe as I was able to get the gpu passed through.

 

[8086:a170] 00:1f.3 Audio device: Intel Corporation 100 Series/C230 Series Chipset Family HD Audio Controller (rev 31)

 

is in an iommu group with a few other devices, including a smbus and this appears to be the root cause.