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Date: Fri, 20 Apr 2007 21:01:01 +0200
From: Rene Herman <rene.herman@gmail.com>
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To: Bart Trojanowski <bart@jukie.net>
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Subject: Re: how to tell linux (on x86) to ignore 1M or memory
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On 04/19/2007 04:18 PM, Bart Trojanowski 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?

Note that real-mode can only access the first megabyte (*) and not the first 
16. 16MB is the 16-bit protected mode (286) limit.

(*) well, the first 1M + 64K - 16 bytes using segment FFFF assuming A20 is 
enabled and x > 1 in x86...

Rene.