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Date: Sat, 27 Jul 1996 22:58:24 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199607271258.WAA11898@godzilla.zeta.org.au>
To: bde@zeta.org.au, se@zpr.uni-koeln.de
Subject: Re: ncr53c810 driver in stable/current
Cc: current@FreeBSD.org, scrappy@ki.net, stable@FreeBSD.org
Sender: owner-current@FreeBSD.org
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>As a work around to those people in need to have
>kernel dumps written to disk on a NCR system: Is
>it worth the effort to detect the special situation
>and have the driver ignore the memory hole in the 
>dump ?

It would have to fill the hole(s) with nulls or
something for compatibility (savecore and gdb don't
understand holes).  To handle this machine-independently,
xddump() should probably write a memory map and not dump
the holes; then savecore should fill the holes with
null blocks.  Otherwise /dev/mem would take more than
2^64 bytes of memory to map on 64-bit systems with
physical memory at high addresses.

Bruce