"find /sys/kernel/iommu_groups/ -type l" does not yield anything

[Murphi]

Hello,

I am stuck with PCIe Passthrough. I would appreciate every bit of help.

My system setup is:
CPU: 2x Intel Xeon E5-2680
MB: ASRock EP2C602-4L/D16
OS: PRoxmox VE 6.0 in UEFI

As far as I know the Hardware supports PCIe Passthrough.

I followed this guide: https://pve.proxmox.com/wiki/PCI(e)_Passthrough

I enabled VT / VT-d Support in the UEFI Setup
modified "/etc/kernel/cmdline" with "intel_iommu=on" in a new line
ran "pve-efiboot-tool refresh"
added all modules listed in the guide to "/etc/modules"
ran "update-initramfs -u -k all"
rebooted

Now the Part where I am stuck:
ran "find /sys/kernel/iommu_groups/ -type l" and i got no output
The Webinterface states "no iommu detected"

If anyone has an idea what the problem is I would appreciate a response. Thanks in advance.

 

[dcsapak]

what does 'cat /proc/cmdline' show ?

 

[Murphi]

what does 'cat /proc/cmdline' show ?

Thanks for the reply.

cat /proc/cmdline outputs:

initrd=\EFI\proxmox\5.3.10-1-pve\initrd.img-5.3.10-1-pve root=ZFS=rpool/ROOT/pve-1 boot=zfs

 

[dcsapak]

this shows that the 'intel_iommu=on' did not make it in the cmdline, thus is not activated

please see again the methods for this in our documentation[0] and check your bootloader config

0: https://pve.proxmox.com/wiki/Host_Bootloader#sysboot_edit_kernel_cmdline

 

[Murphi]

I have read that guide and applied it. The only problem: if I write following in /etc/kernel/cmdline :

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

Proxmox won`t boot anymore. Only into initramfs

I tried it with grub, but that didn't have any effect. cat /proc/cmdline showed:

initrd=\EFI\proxmox\5.3.10-1-pve\initrd.img-5.3.10-1-pve root=ZFS=rpool/ROOT/pve-1 boot=zfs

 

[KenRQ]

Did you run "pve-efiboot-tool refresh" after adding the entry into /etc/kernel/cmdline and re-boot? I was having the same issue as you with nothing listed in the /sys/kernel/iommu_groups directory until I did this.