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Date: Wed, 26 Apr 1995 17:57:58 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199504260757.RAA10941@godzilla.zeta.org.au>
To: dufault@hda.com
Subject: Re: panic: pmap_zero_page: CMAP busy
Cc: current@freefall.cdrom.com
Sender: current-owner@FreeBSD.org
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>The panic is caused by the difference between these two lines in
>the config:

>>From GENERIC (works):
>> config		kernel	root on wd0 swap on wd0 and wd1 and wd2 and vn0 dumps on wd0

>>From DESMOND (panics):
>> config		kernel	root on wd0 swap on wd0 dumps on wd0

Maybe this has something to do with the bogus test for the end of
swdevt[] in i386/autoconf.c.  The array is terminated by device NODEV
but device 0 is tested for (the test for > 0 degenerates to == 0
because dev_t is unsigned).  Apparently there are usually 0's sufficiently
close to the end of swdevt[] for there to be no problems.

Bruce