vga passthrough // questions about pci passthrough

From: Martin Wolf <mwolf@adiumentum.com>
To: kvm@vger.kernel.org
Subject: vga passthrough // questions about pci passthrough
Date: Wed, 18 Jul 2012 07:45:43 +0200	[thread overview]
Message-ID: <50064D87.2090809@adiumentum.com> (raw)

Hello,

i was able to passthrough an AMD 7870 videocard to my win7 guest machine.
my host is ubuntu 12.04 with stock kernel.
my system contains:
dq67sw q67 mainboard
i5-2400s cpu
sapphire 7870 amd videocard
xonar d2x (problems to passthrough)

for full functionality i just needed two options

- kernel : iommu=on
- kvm module: ignore_msrs=1
(if i would not set it the guest os would crash with a bluescreen)

the unigine benchmark ran flawlessly
also the benchmark included in windows gave my videocard
similar values (7.7) comparable with my native win7 (7.9)

now to my questions...
1. 	is it possible to reset the videocard properly to be able to
	reboot the vm?

2.	the xonar d2x is a very nice audio card, it would be very handy
	to be able to use it in the vm. in my oppinion the card is a
	d2 with a pci-e to pci bridge.
	i tried to passthrough the card alone and with the pci-bridge
	that was shown though lspci, but i had no success.
	maybe you guys here have an idea on that topic?

thank you for you great work ;)