From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jan Kiszka <jan.kiszka@siemens.com>
Subject: Re: Direct guest device access from nested guest
Date: Wed, 28 Aug 2013 20:18:21 +0200
Message-ID: <521E3EED.2080702@siemens.com>
References: <87sixtsxdj.fsf@fimbulvetr.bsc.es> <521E29F5.3070000@siemens.com> <87ppsxelbf.fsf@fimbulvetr.bsc.es>
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Cc: qemu-devel@nongnu.org, kvm <kvm@vger.kernel.org>
To: =?ISO-8859-15?Q?Llu=EDs_Vilanova?= <vilanova@ac.upc.edu>
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On 2013-08-28 20:12, Llu=EDs Vilanova wrote:
> Jan Kiszka writes:
> [...]
>>> Is it possible to give a nested guest direct access to a device on =
the guest?
>>> (more specifically, an AHCI controller).
>=20
>> Nope, we are lacking support for emulating or (securely) forwarding
>> VT-d/IOMMU features to the first level guest. Would be cool to have,
>> just not yet there. But I've talked to Intel people recently, and th=
ey
>> are considering to support some nested VT-d with KVM.
>=20
> Thanks a lot. I've been told there's some patches floating around to =
add such
> support, but I suppose they've been long outdated and only work as PO=
Cs.

I haven't seen anything in public.

Jan

PS: You have Mail-Followup-To set in your answers - people will drop yo=
u
from CC this way.

--=20
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