From owner-freebsd-geom@FreeBSD.ORG  Tue Feb  1 19:18:40 2011
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Date: Tue, 01 Feb 2011 10:39:18 -0800
From: Matthew Jacob <mj@feral.com>
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Cc: 
Subject: setting a dump device as a side effect of getattr
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The current mechanism for setting a dump device is to run down the list 
of geoms and call set_dumper at the bottom layer.

Would anyone object to making the caller of the GETTATTR for 
GEOM::kerneldump responsible for calling set_dumper (if desired)?

This gives systems some flexibility in changing or extending dump 
devices w/o having to play games witth doing save of the current dumper, 
calling the GETATTR, restoring the current dumper and so on.