In my experience, if you want to pass a device through to the VM, the host driver has to be detached, in which case it'll show up in pciconf -l output as none@pci.... So I'm not sure how this can work.

The example is indeed incorrect, as the driver would have to be detached first. bhyve works by passing it a ppt driver, so none (although the script will still be able to fetch its bus/slot/func) isn't supposed to be used either.

https://wiki.freebsd.org/bhyve/pci_passthru

The example should say ppt0 instead of ehci0.

I'll fix this in another commit because there are multiple other instances of this.

Ah right, ok.

Can we please also preserve backward compatibility? That is, if the passthrough device is of the form a/b/c, avoid treating it as a device name?

I think you can replace this pipe with passno=$(pciconf -l | awk -F: '{print $2"/"$3"/"$4}').

Sure.

Thank you, definitely better this way

Sorry, I meant to write pciconf -l $pass| awk -F: '{print $2"/"$3"/"$4}'.

I'd also name the variable something more accurate, maybe "bsl" (bus slot function).

[0-9]* matches the empty string, but we don't want that.

Sorry, I meant to write "bsf".

Don't we need to preserve the domain as well?

Sorry, I meant to write "bsf".

I didn't think about it at all, thanks.

bhyve expects bus/slot/entry as input, so the domain field is not needed in this case.