Replying to a message of Don Hills to Rich:

 >>   As for identifying compatible devices, mca lacks this mechanism. It's
 >> entirely a guessing game.  The PCI approach is that the device
 >> identifies with what it is compatible.

 DH> That wasn't allowed. The device driver had to recognise the adapter
 DH> ID. This ensured that the device driver had actually been tested with
 DH> the adapter and proven to work reliably. Mainframe mindset.

That 'mainframe mindset' has worked well for over half a century.  I have never
heard of an IBM mainframe OS crashing absent some hardware failure.  We did
manage to occasionally crash a Honeywell OS thirty years ago, though, but our
particular version of the OS was heavily patched and thus 'nonstandard'.

--- FleetStreet 1.19+