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To: dg@root.com
Subject: Re: self modifying kernel code 
Cc: Steve Passe <smp@csn.net>, smp@freebsd.org, current@freebsd.org
In-reply-to: Your message of "Wed, 16 Jul 1997 17:40:42 PDT."
		<199707170040.RAA04953@implode.root.com> 
References: <199707170040.RAA04953@implode.root.com>  
Date: Wed, 16 Jul 1997 23:30:42 -0600
From: Warner Losh <imp@rover.village.org>
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In message <199707170040.RAA04953@implode.root.com> David Greenman writes:
:    I'd say that you'd get less resistence to it, but then at boot time there
: are probably other cleaner, slower, ways of accomplishing the same thing.

I know that the MIPS based OSes generally bcopy a routine into the
trap handler location based on what architecture it is running (MIPS I
or MIPS III) on.  The MIPS hardware wants this trap routine to be of a
certain size at a fixed location.  Since this is for TLB handling, and
there are a limited number of TLB slots, this routine generally is as
hand tweaked as you can get.

Warner