IOMMU not activatable - UEFI systemd boot

[Vin]

Hello everybody,

I did read many threads on the forum and via google search, yet I cannot find any solution to my problem.

I have a Asrock Z790 Pro RS/D4 mainboard with vt-d enabled.

I installed Proxmox via UEFI and setup a ZFS Raid 0 NVMe Pool.

I used previously working GPU passhtrough guides, to enable IOMMU and pass my GPU to my VM, but since I didnt use legacy to install proxmox, I cant seem to enable IOMMU anymore.

I already tried following


GRUB - /etc/default/grub

• GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on iommu=pt initcall_blacklist=sysfb_init"
• update-initramfs -u -k all
• update-grub

Kernel - /etc/kernel/cmdline

• intel_iommu=on
• rootdelay=10
• pve-efiboot-tool refresh

cat /etc/kernel/cmdline returns following

• root=ZFS=rpool/ROOT/pve-1 boot=zfs
• intel_iommu=on
• rootdelay=10

 

[Stoiko Ivanov]

cat /etc/kernel/cmdline returns following

• root=ZFS=rpool/ROOT/pve-1 boot=zfs
• intel_iommu=on
• rootdelay=10

for systemd-boot you need to use /etc/kernel/cmdline - however all parameters need to go into one single line!

afterwards you need to run `proxmox-boot-tool refresh`

please use code-tags and paste the contents of the files as they are literally - makes analyzing the situation a bit easier.

I hope this helps!

 

[Vin]

Thank you so much for your answer!

for systemd-boot you need to use /etc/kernel/cmdline - however all parameters need to go into one single line!

That was the tip i needed, I can pass the GPU now

But the driver seems to crash at the login screen of windows 11, restart and then constantly glitch in various colours etc.

Are there any specific settings for UEFI boot I m missing?

I used following settings to passthrough the gpu

GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on iommu=pt initcall_blacklist=sysfb_init"

nano /etc/modules


vfio
vfio_iommu_type1
vfio_pci
vfio_virqfd

echo "blacklist radeon" >> /etc/modprobe.d/blacklist.conf
echo "blacklist nouveau" >> /etc/modprobe.d/blacklist.conf
echo "blacklist nvidia" >> /etc/modprobe.d/blacklist.conf

Also I use the GPU fix, since I dont have an intel IGPU via crontab

nano /fix_gpu_pass.sh
 
#!/bin/bash
echo 1 > /sys/bus/pci/devices/0000\:01\:00.0/remove
echo 1 > /sys/bus/pci/rescan

 

[Vin]

Can nobody help?

I get the dmesg terminal shown during windows boot and the driver seems to have issues like in the picture below, its flickering and crashing constantly.

Is there anything to fix this behaviour? I reinstalled Windows and Proxmox already a couple of times

 

[leesteken]

Check with cat /proc/cmdline if the boot GPU passthrough work-aaround initcall_blacklist=sysfb_init is active. Check according to the Proxmox manual which bootloader is used on your system. Change the right kernel parameters if necessary.