Review/Test: Pseudo-device unit number management patch

[M. Warner Losh]

In message: <39796.1077013415 at critter.freebsd.dk>
            "Poul-Henning Kamp" <phk at phk.freebsd.dk> writes:
: Current our handing is that if it disappears, it's gone, if it comes
: back it's probably a new one anyway.

Yes.  If the hardware goes away and comes back, it can be very
difficult to know if you have the same hardware or different
hardware.  This is less true of network cards, but definitely true of
CF cards (which can easily be identical from inspection, but have
different contents).

Warner