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Date: Fri, 25 Apr 2003 16:15:42 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
Organization: Zytor Communications
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To: "Martin J. Bligh" <mbligh@aracnet.com>
CC: Timothy Miller <miller@techsource.com>, linux-kernel@vger.kernel.org
Subject: Re: TASK_UNMAPPED_BASE & stack location
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Martin J. Bligh wrote:
>>>128Mb of it? The bottom page, or even a few Mb, sure ... 
>>>but 128Mb seems somewhat excessive ..
>>> 
>>>
>>
>>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.
> 

As far as I know, you're perfectly free to move the stack whereever you
feel like, as long as you map the space first, copy the contents and set
%esp.  mremap() is useful for this.

	-hpa