From owner-freebsd-hackers  Mon Sep 24 18:14:54 2001
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To: Matt Dillon <dillon@earth.backplane.com>
Cc: Ian Dowse <iedowse@maths.tcd.ie>,
	Julian Elischer <julian@elischer.org>, hackers@FreeBSD.ORG
Subject: Re: VM Corruption - stumped, anyone have any ideas? 
In-reply-to: Your message of "Mon, 24 Sep 2001 17:27:27 PDT."
             <200109250027.f8P0RRk97980@earth.backplane.com> 
Date: Mon, 24 Sep 2001 18:14:34 -0700
From: Bakul Shah <bakul@bitblocks.com>
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FWIW, in a Unix port we did I remember putting the user
struct *above* the kernel stack.  The stack grew down so you
hit the red zone (the guard pages) without clobbering the
user struct.  Since struct user _ended_ on a page boundary,
its size was needed at locore.s assembly time but that was a
small price to pay for the added safety.

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