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Date: Wed, 24 Aug 2011 11:14:26 +0200
From: "Roedel, Joerg" <Joerg.Roedel@amd.com>
To: aafabbri <aafabbri@cisco.com>
Subject: Re: kvm PCI assignment & VFIO ramblings
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On Tue, Aug 23, 2011 at 12:54:27PM -0400, aafabbri wrote:
> On 8/23/11 4:04 AM, "Joerg Roedel" <joerg.roedel@amd.com> wrote:
> > That is makes uiommu basically the same as the meta-groups, right?
> 
> Yes, functionality seems the same, thus my suggestion to keep uiommu
> explicit.  Is there some need for group-groups besides defining sets of
> groups which share IOMMU resources?
> 
> I do all this stuff (bringing up sets of devices which may share IOMMU
> domain) dynamically from C applications.  I don't really want some static
> (boot-time or sysfs fiddling) supergroup config unless there is a good
> reason KVM/power needs it.
> 
> As you say in your next email, doing it all from ioctls is very easy,
> programmatically.

I don't see a reason to make this meta-grouping static. It would harm
flexibility on x86. I think it makes things easier on power but there
are options on that platform to get the dynamic solution too.

	Joerg

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