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Date: Fri, 25 Apr 2003 14:10:32 -0700
From: "Martin J. Bligh" <mbligh@aracnet.com>
To: "H. Peter Anvin" <hpa@zytor.com>, linux-kernel@vger.kernel.org
Subject: Re: TASK_UNMAPPED_BASE & stack location
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>> Is there any good reason we can't remove TASK_UNMAPPED_BASE, and just
>> shove libraries directly above the program text? Red Hat seems to have
>> patches to dynamically tune it on a per-processes basis anyway ...
>> 
>> Moreover, can we put the stack back where it's meant to be, below the
>> program text, in that wasted 128MB of virtual space? Who really wants 
>> > 128MB of stack anyway (and can't fix their app)?
> 
> That space is NULL pointer trap zone.  NULL pointer trapping -> good.

128Mb of it? The bottom page, or even a few Mb, sure ... 
but 128Mb seems somewhat excessive ...

M.