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From: John Baldwin <jhb@freebsd.org>
To: Andriy Gapon <avg@freebsd.org>
Date: Wed, 11 Jan 2012 17:40:31 -0500
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	(bigwig.baldwin.cx); Thu, 12 Jan 2012 07:35:38 -0500 (EST)
Cc: freebsd-current@freebsd.org
Subject: Re: bus dma: a flag/quirk for page zero
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On Wednesday, January 11, 2012 2:56:47 pm Andriy Gapon wrote:
> on 11/01/2012 19:18 Andriy Gapon said the following:
> > Actually, I think that on x86 we don't have to do anything special for any memory
> > allocations that we do, including the bounce pages, as the page zero is excluded
> > from phys_avail and is not available for normal use.
> 
> After some additional thinking there is probably no reason to take advantage of
> this fact.  First, it would increase differences with other platforms.  Second,
> it would add a hidden dependency.  So it's better to be explicit here.

Agreed.

-- 
John Baldwin