kern/102766: geom panics when devices go away

[Poul-Henning Kamp]

In message <200609021024.k82AO8Sp025334 at freefall.freebsd.org>, Pawel Jakub Dawi
dek writes:

>Take this PR. I still think such situations should be handled in
>GEOM, not in every single GEOM class. ehh.

Only the classes know how to handle this, GEOM shouldn't try to
guess the internal logic of GEOM classes.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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