I think that's true outside of s390, but a standardized virtual device
interface should be able to work there as well. Interestingly, the
s390 channel I/O also uses two 16 bit numbers to identify a device
(type and model), just like PCI or USB, so in that light, we might
be able to use the same number space for something entirely different
depending on the virtual bus.
Arnd <><
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