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To: Steve Passe <smp@csn.net>
cc: smp@FreeBSD.ORG, current@FreeBSD.ORG
Subject: Re: self modifying kernel code 
In-reply-to: Your message of "Wed, 16 Jul 1997 18:33:22 MDT."
             <199707170033.SAA10984@Ilsa.StevesCafe.com> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Wed, 16 Jul 1997 17:40:42 -0700
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>>    Basically, we don't allow self-modifying code. There are many reasons, for
>> instance the kernel text is protect read-only to catch certain types of bad
>> pointer references, but the main reason is that it's considered bad programming
>> style, obscuring the operation of the code - usually with little or no gain.
>
>I expected this, how about during boot as oppossed to while running?

   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.

-DG

David Greenman
Core-team/Principal Architect, The FreeBSD Project