Configure Proxmox GPU Passthrough (Step-by-Step Tutorial)

This tutorial provides a comprehensive guide on installing and configuring GPU passthrough in Proxmox for use with a Windows 11 virtual machine. This step-by-step guide offers clear instructions and explanations to navigate the process smoothly. From understanding the basics of GPU passthrough to completing the installation, users will find all the necessary guidance here.

Step by Step tasks:

Step 1: Edit GRUB
Execute: nano /etc/default/grub
Change this line from
GRUB_CMDLINE_LINUX_DEFAULT="quiet"
to
GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on iommu=pt pcie_acs_override=downstream,multifunction nofb nomodeset video=vesafb:off,efifb:off"
Save file and exit the text editor

Step 2: Update GRUB
Execute the command: update-grub

Step 3: Edit the module files
Execute: nano /etc/modules
Add these lines:
vfio
vfio_iommu_type1
vfio_pci
vfio_virqfd
Save file and exit the text editor

Step 4: IOMMU remapping
a) Execute: nano /etc/modprobe.d/iommu_unsafe_interrupts.conf
Add this line:
options vfio_iommu_type1 allow_unsafe_interrupts=1
Save file and exit the text editor
b) Execute: nano /etc/modprobe.d/kvm.conf
Add this line:
options kvm ignore_msrs=1
Save file and exit the text editor

Step 5: Blacklist the GPU drivers
Execute: nano /etc/modprobe.d/blacklist.conf
Add these lines:
blacklist radeon
blacklist nouveau
blacklist nvidia
blacklist nvidiafb
Save file and exit the text editor

Step 6: Adding GPU to VFIO
a) Execute: lspci -v
Look for your GPU and take note of the first set of numbers
b) Execute: lspci -n -s (PCI card address)
This command gives you the GPU vendors number.
c) Execute: nano /etc/modprobe.d/vfio.conf
Add this line with your GPU number and Audio number:
options vfio-pci ids=(GPU number,Audio number) disable_vga=1
Save file and exit the text editor

Step 7: Command to update everything and Restart
a) Execute: update-initramfs -u
b) Then restart the your Proxmox Node



Additional information for Integrated GPU passthrough process:

*** Configuration for Intel Integrated GPU passthrough:

This example is for an Intel I5-7600 CPU with a HD Graphics 630 iGPU

VM should be configured the Machine type:
Windows: q35
Linux: Default(i440fx)

Execute: nano /etc/default/grub

Replace the current line by this one

GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on i915.enable_gvt=1 iommu=pt pcie_acs_override=downstream,multifunction video=efifb:off video=vesa:off vfio_iommu_type1.allow_unsafe_interrupts=1 kvm.ignore_msrs=1 modprobe.blacklist=radeon,nouveau,nvidia,nvidiafb,nvidia-gpu"

Execute: update-grub

Execute: nano /etc/modules

Add all these lines to the file:
vfio
vfio_iommu_type1
vfio_pci
vfio_virqfd
kvmgt

Execute: nano /etc/modprobe.d/vfio.conf
Include your iGPU number, you can specify multiple GPU separated with a coma
(ie:1882:61de,1882:bbf1,8086:5803)

options vfio-pci ids=(GPU number) disable_vga=1

Execute: update-initramfs -u -k all

Reboot your Proxmox Server Node

In the VM Hardware:
Uncheck All Function
Uncheck PCI-Express

Reboot your VM

Voila it should work!