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Date: Sat, 20 Oct 2001 11:09:24 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
Organization: Zytor Communications
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To: landley@trommello.org
CC: Timur Tabi <ttabi@interactivesi.com>, linux-kernel@vger.kernel.org
Subject: Re: Allocating more than 890MB in the kernel?
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Rob Landley wrote:

> 
> Each user process has 32 bit pointers for memory.  This means they only have 
> 4 gigabytes of virtual address space, regardless of how many physical pages 
> the machine has.  The kernel doesn't use segment:offset addressing.  It just 
> uses the offset.  Flat memory model.
> 


And even if it did (on i386) it wouldn't help... the segment:offset is 
folded into a single 32-bit space before paging.

	-hpa


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