Windows VM Wont Boot After Attaching GPU

rbeard.js

Member
Aug 11, 2022
53
2
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Hello there!
Its my first time setting up and learning proxmox and so far it has been great!
I have a windows virtual machine that im trying to pass a nvidia gpu to. I followed this guide in order to configure (https://www.reddit.com/r/homelab/comments/b5xpua/the_ultimate_beginners_guide_to_gpu_passthrough/).
I had to set the "Important Additional Commands" in my grub because without them, it was still saying my iommu was turned off when I went to attach my gpu.

Ive check all my settings multiple times but I cant get the machine to boot with the card attached. I had previously done this with an amd card on the same machine and that worked just fine.

Any ideas as to why this is happening?
Thank.you
 
nofb nomodeset video=vesafb:off,efifb:off doesn't really do anything (anymore). Try replacing all of that with initcall_blacklist=sysfb_init, which appears to be a necessary work-around for kernel 5.15 and higher.
I'm assuming a lot here but you give very little information. We can go through the whole process of questions and answer when this does not resolve your issue.
Didn't you have the problem of "saying my iommu was turned off" when doing the passthrough of the AMD GPU?
 
Im sorry Im mot trying to be vague, my server is shutdown so I couldnt access it to get the error log.
I didnt have to put that extra line for the amd card, it worked without it.
I can try that line you provided and report back! Thank you!
 
nofb nomodeset video=vesafb:off,efifb:off doesn't really do anything (anymore). Try replacing all of that with initcall_blacklist=sysfb_init, which appears to be a necessary work-around for kernel 5.15 and higher.
I'm assuming a lot here but you give very little information. We can go through the whole process of questions and answer when this does not resolve your issue.
Didn't you have the problem of "saying my iommu was turned off" when doing the passthrough of the AMD GPU?

So I added the changes to my grup.conf as you suggested and the Vm now boots but now Im dealing with code 43 in device manager.
I did some searching and added some args into the vm config but Im still having persisting issues. Im trying to passthrough a Nvidia Quadro NVS 510 which is probably adding to the issues. I can send over my configuration information this time:
GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on iommu=pt pcie_acs_override=downstream.multifunction initcall_blacklist=sysfb_init"

agent: 1
args: -cpu 'host,+pdpe1gb,+kvm_pv_unhalt,+kvm_pv_eoi,hv_spinlocks=0x1fff,hv_vapic,hv_time,hv_reset,hv_vpindex,hv_runtime,hv_relaxed,hv_synic,hv_stimer,hv_tlbflush,hv_ipi,kvm=off,hv_vendor_id=Nvidia43FIX'
bios: seabios
boot: order=virtio0;ide2;net0
cores: 2
cpu: host
hostpci0: 0000:03:00,pcie=1
ide2: none,media=cdrom
machine: pc-q35-6.1
memory: 8192
meta: creation-qemu=6.1.0,ctime=1659546766
name: *******
net0: virtio=MACADDRESSHERE,bridge=vmbr0,firewall=1
numa: 0
onboot: 1
ostype: win10
scsihw: virtio-scsi-pci
smbios1: uuid=12f1b12b-8aaa-48bc-8bb9-9f731e3b9484
sockets: 2
vga: virtio
virtio0: carbon:vm-102-disk-0,size=256G
vmgenid: c127b148-8557-4814-a41d-5df547092957
 
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I have no experience with NVidia or Windows. I would try removing the args: -cpu 'host,+pdpe1gb,+kvm_pv_unhalt,+kvm_pv_eoi,hv_spinlocks=0x1fff,hv_vapic,hv_time,hv_reset,hv_vpindex,hv_runtime,hv_relaxed,hv_synic,hv_stimer,hv_tlbflush,hv_ipi,kvm=off,hv_vendor_id=Nvidia43FIX' from the VM configuration. Usually enabling Primary GPU helps with NVidia consumer GPUs. I advise disabling automatic starting the VM on boot until it's stable to prevent infinite reboot loops when something goes wrong.
NVidia no longer actively blocks virtualization and for Quadro's this is a supported use case, but people don't like it when I suggest asking NVidia (directly via support or a forum or something). Maybe someone else has experience with your GPU on a Windows VM.
 
Enabling Primary GPU does cause the VM not to boot unfortunately.
I can absolutely remove that args bit as it doesnt seem to have changed anything for the worse of better.
I saw that too where they are supporting these use cases. Im using the most current drivers available.. maybe someone will come along that has more experience like you mentioned. I really do appreciate all the help though!
 

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