From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <ian.campbell@citrix.com>
Subject: Re: PCI Passthrough ARM Design : Draft1
Date: Fri, 12 Jun 2015 12:52:02 +0100
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To: Julien Grall <julien.grall@citrix.com>
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On Fri, 2015-06-12 at 07:41 -0400, Julien Grall wrote:

> I was suggesting to expose the host layout to the guest layout (similar 
> to e820).

We do this on x86 only as a workaround for broken hardware (essentially
magic system devices which bypass the IOMMU).

We shouldn't do this on ARM by default, but only as and when a similar
requirement arises.

> Although, this is not my preferred way and a non 1:1 mapping would be 
> the best.

Yes, a non-1:1 mapping is the right answer.

Ian.