USB devices with same vendor:product id

Pol Van Aubel libvirt at
Mon Feb 3 15:16:10 UTC 2020

Quoting Ján Tomko (2020-02-03 14:45:38)
> There has been a proposal (or two?) for addressing USB hostdevs by bus/port
> Sadly it never landed upstream.

Regarding that patch, as I mentioned in another reply, *USB* bus numbers
on Linux aren't stable -- see

("Each device's dev->devpath will be stable until USB is re-cabled, and hubs
are often labeled with these port numbers.  The name isn't as stable:
bus->busnum changes easily from modprobe order, cardbus or pci hotplugging, and
so on.")

So unless it uses PCI devpaths, which from a quick glance at the code I
don't think it does, that doesn't actually solve the problem of changing
*bus* numbers -- it only solves the problem of changing *device* numbers
under an assumed-to-be-but-not-actually stable bus.

-- Pol

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