You found that you are using systemd, adding bits to GRUB will not work. Instead, follow these steps:
Open the /etc/kernel/cmdline file for editing:
nano /etc/kernel/cmdline
Add the following line for AMD CPUs:
root=ZFS=rpool/ROOT/pve-1 boot=zfs amd_iommu=on iommu=pt pcie_acs_override=downstream,multifunction
note: For intel, just replace amd
with intel
, like so: intel_iommu=on
After editing the /etc/kernel/cmdline
file, refresh the boot tool by running:
proxmox-boot-tool refresh
With these steps, you should have successfully enabled IOMMU and ACS patch using systemd for your Proxmox installation.