Odyssey Blue X86J4125 and IOMMU

Products & Technology ODYSSEY Serials
#1

I’m trying to configure the Odyssey Blue X86J4125 to use IOMMU.
The latest firmware is installed dated 05/20/2022.
In the CMOS, CMS Support is enabled. It shows the CSM16 Module Version 07.82.
Network is the default UEFI

Under debian, when I run dmesg and search for IOMMU, I expect to see that it is enabled, but I get something else.

dmesg | grep IOMMU
[ 0.112007] DMAR-IR: IOAPIC id 1 under DRHD base 0xfed65000 IOMMU 1

In Proxmox-Hardware, when I try to add a PCI device I get
No IOMMU detected, please activate it.See Documentation for further information.

There are also configuration settings for a Network Stack Configuration, and the default is Disabled, are the defaults OK?

This board is the X86J4125 V1, is there a difference in IOMMU with V2?

In the big picture, I want to run Proxmox and either OpenWRT or pfSense but without IOMMU support this will not work.

Thanks

#2

Hello,

Since no one has answered this and I ran into the same issue, I’ll add my solution here.

I ran into a similar problem where I needed VMs to share PCI slots. I reached out to seeed tech support, and there is support in the BIOS under Advanced → CPU Configuration → VT-d (reference). Enabling the VT-d setting and saving the BIOS config enables IOMMU.

Since I already had that enabled, I went searching on the proxmox side, and found this Proxmox forum post, which after following the steps to update the GRUB configuration listed therein by leesteken and reboot, I was able to share single PCI devices into VMs:

Specifically, I:

  1. In /etc/default/grub, to GRUB_CMDLINE_LINUX I appended intel_iommu=on to any other options (there were none).
  2. Ran sudo update-grub
  3. Rebooted
  4. Ran cat /proc/cmdline to confirm that intel_iommu=on was amongst the other options.
  5. Loaded the Proxmox GUI, no longer received the IOMMU warning, and was able to add map PCI devices into VM configurations using Raw Device mode.

HTH.

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