From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <ian.campbell@citrix.com>
Subject: Re: Xen PV IOMMU interface draft C
Date: Mon, 29 Jun 2015 16:36:02 +0100
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To: David Vrabel <david.vrabel@citrix.com>
Cc: Kevin Tian <kevin.tian@intel.com>, "Zhang, Yu C" <yu.c.zhang@intel.com>, Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>, Andrew Cooper <andrew.cooper3@citrix.com>, Julien Grall <julien.grall@citrix.com>, Paul Durrant <Paul.Durrant@citrix.com>, "Lv,
	Zhiyuan" <zhiyuan.lv@intel.com>, Jan Beulich <JBeulich@suse.com>, xen-devel <xen-devel@lists.xenproject.org>, Malcolm Crossley <malcolm.crossley@citrix.com>
List-Id: xen-devel@lists.xenproject.org

On Mon, 2015-06-29 at 16:24 +0100, David Vrabel wrote:
> On 29/06/15 15:52, Ian Campbell wrote:
> > On Mon, 2015-06-29 at 10:40 -0400, Konrad Rzeszutek Wilk wrote:
> >> On Fri, Jun 26, 2015 at 12:03:44PM +0100, Ian Campbell wrote:
> >>> +ARM devs.
> >>>
> >>> On Fri, 2015-06-26 at 11:23 +0100, Malcolm Crossley wrote:
> >>>> Hi All,
> >>>
> >>> I had a chat with Malcolm about this with respect to ARM.
> >>>
> >>> The upshot is that this does not help us to remove the dom0 1:1
> >>> workaround or associated swiotlb uses on systems without an SMMU, nor
> >>> does it allow us to sensibly do passthrough on systems which lack an
> >>> SMMU.
> >>
> >> What would?
> > 
> > This "Xen PV IOMMU interface".
> 
> I guess Konrad is asking if this PV IOMMU interface doesn't solve these
> problems, what (other possible interface) would?

Ah, I thought it was a response to the this in "... that this doest
not...".

> I guess the answer is a SMMU?

That's the only solution I've thought of, yes.

Ian.