[dottedmag]

Author here. Thanks, I'll give it a whirl!

Not sure it will work though: I need to add an option to a `pcie-root-port` command-line argument managed by libvirt.

I can try skipping creating `pcie-root-port`s by libvirt completely, and add them manually using options passthrough, but I'm not sure the rest of libvirt won't throw a fit when it finds other devices that refer to these (unknown to libvirt) PCIe slots.