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To: kristyn@gnu.ai.mit.edu
cc: questions@freebsd.org (FreeBSD Questions)
Subject: Re: Help with CMAP error? 
In-reply-to: Your message of "Sun, 05 Jan 1997 22:54:05 EST."
             <199701060354.WAA10277@hill.gnu.ai.mit.edu> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Sun, 05 Jan 1997 22:08:52 -0800
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>  I got this this evening:
>	panic: pmap_zero_page: CMAP busy
>
>  I got this while I was using the IPFilter and NAT and browsing from a
>machine behind the gateway.  What does it mean?

   It usually means that a demand-zero page fault occurred at interrupt time
and while a demand-zero fault was being handled previous to the interrupt.
Page faults are not allowed at interrupt time for any reason, and this most
likely indicates a software bug - a bogus pointer dereference.

-DG

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