How to Fix Proxmox PCIe Passthrough on HP ProLiant G8 Servers #

Written 02/26/25
PROMPT: You are running into trouble while attempting to pass through a PCIe device to a VM in Proxmox running on a HP Proliant G8 Server (e.g. DL360p)

Resources: #

Killer129’s fix to the issue and deep dive of the problem
Request to add fix to kernel

Prerequisites: #

• Luckily for us this is a solved problem and only requires the fix to be enabled. The only requirement is to be running on Proxmox 8 or later. Older versions will still need the kernel patch applied manually.

Steps: #

1. Via the web Shell or direct console to the Proxmox host, run nano /etc/default/grub to modify the grub settings.
2. Update one of the options in GRUB_CMDLINE_LINUX_DEFAULT from intel_iommu=on to intel_iommu=on,relax_rmrr.
3. Write out and close nano, then run update-grub in the shell.
4. Reboot the Proxmox host.