From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?utf-8?Q?Llu=C3=ADs_Vilanova?= <vilanova@ac.upc.edu>
Subject: Re: Direct guest device access from nested guest
Date: Wed, 28 Aug 2013 21:12:36 +0300
Message-ID: <87ppsxelbf.fsf@fimbulvetr.bsc.es>
References: <87sixtsxdj.fsf@fimbulvetr.bsc.es> <521E29F5.3070000@siemens.com>
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Cc: qemu-devel@nongnu.org, kvm <kvm@vger.kernel.org>
To: Jan Kiszka <jan.kiszka@siemens.com>
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In-Reply-To: <521E29F5.3070000@siemens.com> (Jan Kiszka's message of "Wed, 28
	Aug 2013 18:48:53 +0200")
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Jan Kiszka writes:
[...]
>> Is it possible to give a nested guest direct access to a device on the guest?
>> (more specifically, an AHCI controller).

> 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 they
> are considering to support some nested VT-d with KVM.

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support, but I suppose they've been long outdated and only work as POCs.


Lluis

-- 
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