iGPU passthrough on Proxmox VE 9.1.1 – VM freezes on boot

[MatHeb]

Hi everyone,


I’m trying to passthrough my Intel iGPU to a Linux VM on Proxmox VE 9.1.1, but the VM consistently freezes as soon as the iGPU is attached via hostpci0.

Here’s what I’ve tried:

• OVMF (UEFI) + q35 machine type
• iGPU bound to vfio-pci
• Kernel params: intel_iommu=on iommu=pt
• i915 blacklisted on the host
• Several tutorials and guides (Proxmox wiki, forum posts, external blogs)

Behavior:

• VM boots normally without the GPU passthrough line.
• When adding hostpci0, the VM freezes during start up.
• Reproduced with different configurations (x-vga, pcie=1, ROM-bar, etc.).

Question:
Is this a known issue or regression in Proxmox VE 9.x regarding iGPU passthrough?
Should I assume a bug and wait for a fix, or is there something obvious I might be missing?


Thanks for any insights!

 

[cheiss]

Hi,

did you check the journal/dmesg for any related messages?

Have you checked that your IOMMU groups are properly set up (pvesh get /nodes/localhost/hardware/pci --pci-class-blacklist "")?
Can you provide your complete VM configuration (qm config <vmid>)?

FYI:

Kernel params: intel_iommu=on iommu=pt

That's quite outdated information, these parameters (or at least, the first one) are not necessary anymore since 8.2, where they became default-on.

 

[chchia]

C

Thread 'Another solution for passthrough intel iGPU'

Nov 28, 2025

previously i shared a solution that to passthrough iGPU to linux vm with working HDMI output, using i915_vbt file method from host machine.

yesterday i found another interesting method, i tested on linux and it worked, and according to the original creator, it should be able to

OpROM/VBIOS for use with GVT-d iGPU passthrough on Proxmox/QEMU/KVM.
Support direct UEFI display output over HDMI, eDP, DVI, and DisplayPort.
Provides perfect display without screen...

• chchia
• Replies: 0
• Forum: Proxmox VE: Installation and configuration

• 

check this, and when you passthrough igpu, make sure your VM display set to none or it will hang.

 

[MatHeb]

Hi everyone,

thanks a lot for your helpful replies!
It turns out the issue was on my side: I hadn’t set the VM Display option to “none” when passing through the iGPU.
After changing that, the VM boots perfectly and the iGPU works as expected inside the guest.

A bit embarrassing that I overlooked such a simple detail, but your hints pointed me in the right direction — really appreciate the support!

Thanks again!
Matthias