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Date: Fri, 25 Apr 2003 22:15:56 -0700
From: "Martin J. Bligh" <mbligh@aracnet.com>
To: Hugh Dickins <hugh@veritas.com>
cc: Timothy Miller <miller@techsource.com>, "H. Peter Anvin" <hpa@zytor.com>,
       linux-kernel@vger.kernel.org
Subject: Re: TASK_UNMAPPED_BASE & stack location
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>> >> 128Mb of it? The bottom page, or even a few Mb, sure ... 
>> >> but 128Mb seems somewhat excessive ..
> 
> Yes.
> 
>> > Considering that your process space is 4gig, and that that 128Mb
>> > doesn't really exist anywhere (no RAM, no page table entries,
>> > nothing), it's really not excessive.  
>> 
>> I need the virtual space.
> 
> Plus you would (very often) get more physical.  i386 ELF text typically
> begins at 0x08048000: putting stack just below text in many cases shares
> page table between stack+text+data, and saves the page table at top of
> user address space.

A fine point - I hadn't thought of that. 
It just seems tidier all around ....

M.