Currently the ESX driver doesn't output `<address type='pci'>` info. It could be useful for virt-v2v, like for decoding /dev/disk/by-path links for an offline VM. Some discussion: https://issues.redhat.com/browse/MTV-3672

There's some info about it here: https://knowledge.broadcom.com/external/article/311606/mapping-pci-slot-numbers-to-guestvisible.html

But it's definitely not complete. There's .vmx configs in libvirt's test suite, and in our vcenter instance, that have pciBridge devices without pciSlotNumbers defined. Maybe there are default values there if they aren't explicitly listed. And there's info elsewhere online about this being dependent on virtualHW.version.

virt-v2v probably doesn't need full PCI topology, like pcie-root-port etc controllers. Maybe that simplifies things.