LF help passing through existing bare metal Windows installation to kvm/virt-manager

angryJellyBean · 07-01-2021, 01:30 AM

I am hoping someone can help me get an existing bare metal Windows 10 installation running properly in a kvm. I mostly followed the arch guide here https://wiki.archlinux.org/title/PCI...rough_via_OVMF to set up kvm/qemu/virt-manager.

I also saw posts such as https://www.reddit.com/r/VFIO/commen...stall_on_disk/ mentioning how to help avoid issues switching between baremetal and host. Although I got lost where he get's into the dmidecode stuff and where to add what, but he said that is not really needed.

Host is Debian Testing. Windows is on an nvme ssd in its own IOMMU group.

mobo: x570 Aorus Pro Wifi
cpu: Ryzen 9 5950x
ssd: Samsung Evo 970 Plus (x2)
gpu1: 6700xt
gpu2: 7750HD
ram: 32GB (2x16GB) G.Skill Ripjaws V Series 3200MHz
psu: Thermaltake Toughpower GF1 850w

I tried creating the vm in Virt-Manager with Create a New Virtual Machine > Manual Install > Followed prompts until the end, checking Customize before Install. I then set firmware to uefi, gave it 16 cores 16GB ram, and added the nvme controller via Add Hardware > PCI Host Device, and selecting the appropriate controller. I then click begin installation and it successfully starts windows.

However, this gives constant BSOD's. I can force them by performing most any actions. Try to install something, "Scan for Hardware Changes" in Device manager, open too many or too big of a program, or even just let it sit long enough.

Event Viewer shows Event IDs 41, 61, and 6008. The other info under the individual ID's suggest it is a power related issue, and Google searches also seem to suggest this, however, all of the posts I find seem to be running baremetal, not VM's. There is nothing captured Host side in the VM's log file.

I don't believe this is a power issue because baremetal Windows runs just fine, even under stress tests like 3DMark, PCMark, Unigine Heaven. And I have never had it bsod even during intense games like cyberpunk, gtav, or the witcher 3.

Does anyone have any idea what's causing this? Am I missing a step? Or possibly some different settings to try?

Thanks for any help, and of course I can provide any other needed info

angryJellyBean · 07-01-2021, 06:54 PM

I seem to have solved this by adding

Code:

<feature policy='require' name='topoext'/>

just before the closing </cpu> tag, to enable hyperthreading, which apparently isn't enabled by default for AMD CPU's. So you must set the TOPOEXT cpuid flag, as suggested in Improving Performance on AMD cpu's here https://wiki.archlinux.org/title/PCI...ce_on_AMD_CPUs.

I am now able to install programs, run benchmarks, etc as normal

Edit: Well that was shortlived. It's back to the usual bsod's