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Date: Thu, 19 Apr 2007 16:30:07 +0200
From: Paolo Ornati <ornati@fastwebnet.it>
To: Bart Trojanowski <bart@jukie.net>
Cc: linux-kernel@vger.kernel.org
Subject: Re: how to tell linux (on x86) to ignore 1M or memory
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On Thu, 19 Apr 2007 10:18:04 -0400
Bart Trojanowski <bart@jukie.net> wrote:

> I need to preserve some state from the bios before entering protected
> mode.  For now I want to copy it into some ram accessible by real-mode,
> say the last megabyte visible in real-mode.
> 
> What's the easiest way to have linux ignore the megabyte starting at 15M?
> 

Documentation/kernel-parameters.txt:

        memmap=nn[KMG]$ss[KMG]
                        [KNL,ACPI] Mark specific memory as reserved.
                        Region of memory to be used, from ss to ss+nn.


So adding this to kernel boot parameters should do the trick:

	memmap=15M$1M

-- 
	Paolo Ornati
	Linux 2.6.21-rc7-CFS-v3-g6262cd9f on x86_64