Proxmox VE 8.1: IOMMU not working after reinstallation

ReD1991

New Member
Apr 9, 2024
21
2
3
Hi all,

First of all, thanks for reading and thanks in advance for your help. I'm pretty new to proxmox, so I don't know if I'm being stupid by asking the obvious or if I'm having a real issue.

In my post this week: this weeks post I found out together with Dunuin that my SSD was failing and I was unable to recover the bootdrive.
So I had to reinstall Proxmox VE. I bought some new hardware to be more redundant and possibly prevent the same issue from happening again.

I bought 2 HDDs for Proxmox to be installed on (ZFS RAID1) and 2 SSDs for the VMs/ISOs (also ZFS RAID1). My motherboard is the MSI PRO B760-P DDR4 II, it has two m.2 NVME connectors. I checked the documentation the first m.2 connector is directly connected to the CPU and the other via Chipset. I tried to make a ZFS pool like this, the second SSD would show up in the UEFI but not under the ZFS function. Something extra strange is that the onboard Ethernet stops working when I install the second SSD in this slot.

So this morning I bought a PCIe to m.2 NVME converter card for the second SSD and was able to create the (ZFS RAID1). Now the real issue, I was able to reclaim my backups from the HDD I mentioned in "this weeks post", via the help of Dunuin from an older post: older post. (credit is, where credit is due).

Now I want to rebuild the VM of W11 that had GPU passthrough enabled, but when I want to add a PCI device the Proxmox popup gives. "No IOMMU detected, please activate it. See Documentation for further information." Nothing has changed in the UEFI however, so I'm puzzeled on what is wrong.

Could use some advice and help.

Kind regards,
ReD1991
 
Hi,

but when I want to add a PCI device the Proxmox popup gives. "No IOMMU detected, please activate it. See Documentation for further information.
since you say you reinstalled you Proxmox VE - have you also actually performed all the steps & checks necessary for PCI passthrough/IOMMU enablement, as laid out in our documentation? https://pve.proxmox.com/pve-docs/pve-admin-guide.html#qm_pci_passthrough

Can you post the output of dmesg | grep -e DMAR -e IOMMU -e AMD-Vi?
 

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