From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xensource.com>
Subject: Re: x86 swiotlb questions
Date: Tue, 19 Dec 2006 14:14:45 +0000
Message-ID: <C1ADA455.6525%keir@xensource.com>
References: <4587EDA3.76E4.0078.0@novell.com>
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On 19/12/06 12:48, "Jan Beulich" <jbeulich@novell.com> wrote:

>> Do we merge okay with lib/swiotlb.c then?
> 
> Not yet - because of the highmem handling needed for i386. I wonder, however,
> how native Linux gets away with not handling this through swiotlb, and why
> nevertheless Xen needs to special case this. Any ideas?

Probably because GFP_KERNEL and GFP_DMA allocations are guaranteed to be
DMAable by 30-bit-capable devices on native, but not on Xen.

 -- Keir