Does SR-IOV require VT-d?

Question

I am trying to use SR-IOV on VMware vSphere 6 with Intel I350-T4 NIC (supports SR-IOV). The CPU does not support VT-d, can I still use SR-IOV?

What can I use to check if BIOS has enabled SR-IOV?

Answer 1

Seems not. I can answer you from linux side: I use SR-IOV on hosts without VT-d enabled in bios.

VT-d allows you only passthrough PCI-devices into guest that it will give it dedicated access to it. (host system will not see this device)

Without VT-d enabled, VFs can be probed on the host system. So you can assign IP and use it as usual device or assign it to another linux namespace if you use container virtualisation and use it inside container.

If you going to use qemu and full virtualisation you can also use virtio emulated bus for passtrough your VF into vm. But I think it will give you less perfomance than with using VT-d technology.

More information about that you can find in this article: 10G NIC performance: VFIO vs virtio - KVM

Answer 2

Yes you need VT-d enabled in BIOS. You are segregating PF into multiple VFs because you want to use VF with VMs. If VT-d is not enabled in bios you would never be configure VMs on OS. So Why are you creating VFs ? that's why you indirectly needed VT-d to be enabled in BIOS so you can assign VF to any VM.