From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christian Tramnitz <chris.ace@gmx.net>
Subject: Re: [PATCH] VT-d: prevent dom0 to use VT-d HW
Date: Tue, 08 Sep 2009 13:43:06 +0200
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Han, Weidong wrote:
> pv-ops dom0 contains Linux upstream VT-d driver, and will go to enable it when VT-d is set in kernel config file. It should not enable VT-d in dom0.
> 
> Currently it already zaps ACPI DMAR signature to prevents dom0 using VT-d HW when VT-d is enabled for Xen. But when VT-d is not enabled for Xen, and VT-d is set in pv-ops kernel config file, pv-ops dom0 will go to enable it. This will results in pv-ops dom0 booting failure. This patch prevents dom0 to use VT-d HW whether VT-d is enabled or disabled for Xen. 

Wouldn't be easier (and more likely to be adopted by upstream) to add a 
Kconfig dependency like "depends on !XEN_DOM0" to VT-d?


Best regards,
   Christian