Subject: Re: Wine & NetBSD?
To: Chuck Cranor <>
From: Jason R Thorpe <>
List: tech-kern
Date: 11/21/2001 09:17:42
On Wed, Nov 21, 2001 at 10:28:46AM -0500, Chuck Cranor wrote:

 > i would like to know where this magic 0x08048000 number comes from
 > and what the ~128MB of address space before "start" is supposed to be 
 > used for now.  does anyone know?

It may be from historical practice in SVR4.  Certainly, ELF targets
in binutils have done this for a very long time.

Digital Unix does this, too, in their ECOFF-format executables, and
places the stack below the .text segment.  It grows down and hits the
natural guard page at 0x0.

 > on the one hand, it seems clear to me that what Wine is doing is 
 > bad form.   on the other hand, irrespective of Wine, it isn't clear
 > to me that UVM should make efforts protect that leading 128MB as 
 > part of the text/data area like it currently does.   but i'm not 
 > sure --- i don't even know why the 128MB gap was put there.

        -- Jason R. Thorpe <>