intel_immou=on gives DMAR: Allocating domain for dcdbas failed

[natten]

Trying to passthrough my nic with proxmox for a pfsense vm.
I tried to follow this: https://pve.proxmox.com/wiki/Pci_passthrough

But when i update grub with GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on" i get the error:
"DMAR: Allocating domain for dcdbas failed" and i lose access to the server.

Dell R710
2xL5640
Proxmox Virtual Environment 4.2-2/725d76f0
Linux 4.4.6-1-pve

 

[sourceminer]

Did you ever solve this? I am getting the same error. Although my passthough seems to be working ok my audio is having issues.

 

[fireon]

Same Error here on Dell T630.