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Subject: Re: Really good idea to allow mmap(0, FIXED)?
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Michael Buesch <mb@bu3sch.de>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
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Date: Thu, 05 Oct 2006 22:58:00 +0100
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Ar Iau, 2006-10-05 am 20:59 +0200, ysgrifennodd Michael Buesch:
> Is is really a good idea to allow processes to remap something
> to address 0?

It is very useful indeed. Consider for example dosemu.

> Besides that, I currently don't see a valid reason to mmap address 0.
> 
> Comments?

User zero is not neccessarily mapped at kernel zero so your argument
isn't portable either.