Message-ID: <4149D4C2.5070907@hp.com>
Date: Thu, 16 Sep 2004 14:00:34 -0400
From: Robert Picco <Robert.Picco@hp.com>
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To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Jesse Barnes <jbarnes@engr.sgi.com>, Bjorn Helgaas <bjorn.helgaas@hp.com>,
       Christoph Lameter <clameter@sgi.com>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       venkatesh.pallipadi@intel.com
Subject: Re: device driver for the SGI system clock, mmtimer
References: <200409161003.39258.bjorn.helgaas@hp.com>	 <200409160909.12840.jbarnes@engr.sgi.com> <1095349940.22739.34.camel@localhost.localdomain>
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Alan Cox wrote:

>On Iau, 2004-09-16 at 17:09, Jesse Barnes wrote:
>  
>
>>I think Christoph already looked at that.  And HPET doesn't provide mmap 
>>functionality, does it?  I.e. allow a userspace program to dereference the 
>>counter register directly?
>>    
>>
>
>It can do but that assumes nothing else is mapped into the same page
>that would be harmful or reveal information that should not be revealed
>etc..
>
>  
>
HPET driver does provide mmap for user programs. 

I agree with caution of other device registers in the same page. 
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