IOMMU enabled but not detected

[leesteken]

This post is giving me some hope since I am running on the very same hardware Minisforum TH50 (cpu: i5-11320h).

The CPU supports VT-d but I don't know if the motherboard supports it (the link does not work and I cannot find TH50 on their website) or if it is enabled in the BIOS.

# cat /proc/cmdline

BOOT_IMAGE=/boot/vmlinuz-6.8.12-2-pve root=/dev/mapper/pve-root ro quiet intel_iommu=on

intel_iommu=on is no longer required; it is on by default since kernel version 6.8.

So, if i am following well, IOMMU groups are missing... but I have no clue how to get it.... HELP...

You need to enable IOMMU or VT-d in the motherboard BIOS (if it is supported by the motherboard).
Update to the latest BIOS? Enable the setting in the BIOS? Contact Minisforum about this?

 

[Steve_B]

It was my fear... but since theChosenSasquatch made it work, I assume that the hardware is supporting it.

Nevertheless, I sent an email to the support.

 

[Steve_B]

So the support answered that the machine is too old to update the firmware.

But no answer if it's compatible or not ...

Si I finally decided my self to dismount my only monitor from my office and go to the garage to check directly the bios and fount the VT-d settings and enable it..

Now I have the groups... and I will be able to pass my iGPU to my homeassistant VM in order to try tu use it within Frigate or more realistically setup a new LXC for Frigate and pass the iGPU to it

Thank you all for this post

 

[theChosenSasquatch]

Hey guys I'm back! With a solution!

backstory: I'm in the middle of trying to debug a packet loss issue between proxmox and an Opnsense VM. It occurs to me that it would be real nice if I could rule out virtual bridge shenanigans by passing though the NIC directly.

I get the usual "No IOMMU Detected" message in the proxmox UI, so I google "Minisforum TH50 iommu" and find a link to a forum post here. This forum post. My unresolved post.

Anyway I took another crack at it, and halfway through dumping the bios I see another thread about a different minisforum PC, where the advanced BIOS options are hidden behind a key combo.

To enable Vt-d IO passthrough on the Minisforum TH50:
Go to BIOS. Hit Alt+F5, then Okay. Save and exit, and enter BIOS again.

Now there is a (frankly overwhelming) "Advanced" and "Chipset" tab.
Under the "Chipset" tab, enter the first option group (forgot the name)
"Enable Vt-d" is in that page, near the top.

Reboot to proxmox, and blam! pass through all the PCIe devices you want