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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Tue, 20 Aug 2013 19:13:17 +1000
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Subject: Re: [Qemu-devel] [PATCH] powerpc iommu: enable multiple TCE requests
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>, Alexander Graf <agraf@suse.de>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, "qemu-ppc@nongnu.org" <qemu-ppc@nongnu.org>, Paul Mackerras <paulus@samba.org>, David Gibson <david@gibson.dropbear.id.au>

On Tue, 2013-08-20 at 11:09 +0200, Paolo Bonzini wrote:
> > Sorry if I miss anything, but is not it what the patch already
> does? :)
> 
> No, you need to expose multitce unconditionally in the device tree.

If I'm not mistaken the multitce kernel side patches are still not
upstream so I disagree. Exposing it will make Linux use it which means
that anything running on 3.10 or 3.11 will become very slow.

So no, multitce should not be exposed if KVM doesn't support it.

Cheers,
Ben.