PCI passthrough without VT-d support


In an attempt to build another home Xen tower, I configured a Dom0 on an older tower. Problem was, PCI passthrough wouldn’t work, despite the CPU supporting VT-x.

From the Unix & Linux Stack Exchange:

Since version 3.0, Xen has provided PCI passthrough to a paravirtual (PV) guest without VT-d CPU/Motherboard extensions.

I’d noticed my PV instances not having this problem.

Xen cannot provide PCI passthrough to a HVM (fully virtualized) guest without VT-d.

And there’s the issue. My Core 2 Duo CPU has VT-x, but not VT-d. Bottom line, if we’re using PV, there may still be some life in our older towers. Otherwise, we’ll have to shell out for some newer hardware.

Still hard to believe a machine I built in the Core 2 Duo days is already considered old. The march of progress…

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