From owner-freebsd-hackers  Tue Oct 28 01:07:21 1997
Return-Path: <owner-freebsd-hackers>
Received: (from root@localhost)
          by hub.freebsd.org (8.8.7/8.8.7) id BAA09091
          for hackers-outgoing; Tue, 28 Oct 1997 01:07:21 -0800 (PST)
          (envelope-from owner-freebsd-hackers)
Received: from Campino.Informatik.RWTH-Aachen.DE (campino.Informatik.RWTH-Aachen.DE [137.226.116.240])
          by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id BAA09084
          for <freebsd-hackers@freefall.FreeBSD.org>; Tue, 28 Oct 1997 01:07:12 -0800 (PST)
          (envelope-from kuku@gilberto.physik.RWTH-Aachen.DE)
Received: from gil.physik.rwth-aachen.de (gilberto.physik.rwth-aachen.de [137.226.30.2]) by Campino.Informatik.RWTH-Aachen.DE (8.8.7/RBI-Z14)
	with ESMTP id KAA02138; Tue, 28 Oct 1997 10:06:31 +0100 (MET)
Received: (from kuku@localhost) by gil.physik.rwth-aachen.de (8.8.5/8.6.9) id KAA08050; Tue, 28 Oct 1997 10:19:11 +0100 (MET)
Message-ID: <19971028101911.51533@gil.physik.rwth-aachen.de>
Date: Tue, 28 Oct 1997 10:19:11 +0100
From: Christoph Kukulies <kuku@gilberto.physik.RWTH-Aachen.DE>
To: Mike Smith <mike@smith.net.au>
Cc: Christoph Kukulies <kuku@gilberto.physik.RWTH-Aachen.DE>,
        Peter Dufault <dufault@hda.com>, freebsd-hackers@freefall.FreeBSD.org
Subject: Re: mmap/mlock problem
References: <19971028082704.21011@gil.physik.rwth-aachen.de> <199710280736.SAA01858@word.smith.net.au>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
X-Mailer: Mutt 0.81e
In-Reply-To: <199710280736.SAA01858@word.smith.net.au>; from Mike Smith on Tue, Oct 28, 1997 at 06:06:24PM +1030
Sender: owner-freebsd-hackers@FreeBSD.ORG
X-Loop: FreeBSD.org
Precedence: bulk

On Tue, Oct 28, 1997 at 06:06:24PM +1030, Mike Smith wrote:
> > 
> > The portion of code behaves correctly when executed in the
> > driver but executed in the user process (being root) it behaves
> > differently. (accessing the memory region mapped by the driver).
> 
> Ah, now I understand.  I think you said this before.

It works! I had to add a volatile to the memory pointer
in the user program (Jonas Olson already advised me to do so).

Thanks to all.

> 
> Can you show us how you are mapping, and then accessing the device?  
> It sounds like you've got something confused in either the driver or 
> the application, as the memory region itself is OK.
> 
> mike
> 

-- 
Chris Christoph P. U. Kukulies kuku@gil.physik.rwth-aachen.de