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Date: Mon, 23 Jan 2006 20:00:08 -0700 (MST)
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To: julian@elischer.org
From: "M. Warner Losh" <imp@bsdimp.com>
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Cc: freebsd-current@freebsd.org, rwatson@freebsd.org
Subject: Re: kernel thread as real threads..
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In message: <43D56E79.60504@elischer.org>
            Julian Elischer <julian@elischer.org> writes:
: > - fork (although davidxu is changing that)
: 
: well, the operation woudll continue for the parent only I woudl assume.
: 
: > (although davidxu is changing that) 
: 
: I'm not convinced that that multiple threads should be allowed to 
: proceed during a fork
: but I can see that not allowing it is more a "foot shooting avoidance" 
: than a requirement.
: it could be allowed that if you do a fork and allow multipel threads to 
: runat the same time
: and end up with an inconsistant address space in the child, then you get 
: what you deserve.
: :-)

Why not?  It is a race no matter what...  And if you do single thread
things, you can run into a bunch of different dead-lock scenarios.  I
helped to find one recently with nfs.

Warner