From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Roedel, Joerg" <Joerg.Roedel@amd.com>
Subject: Re: [PATCH v5] KVM: VMX: Execute WBINVD to keep data consistency
 with assigned devices
Date: Tue, 29 Jun 2010 14:32:32 +0200
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Cc: Jan Kiszka <jan.kiszka@siemens.com>,
	Sheng Yang <sheng@linux.intel.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	"Yaozu (Eddie) Dong" <eddie.dong@intel.com>
To: Avi Kivity <avi@redhat.com>
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On Tue, Jun 29, 2010 at 06:42:57AM -0400, Avi Kivity wrote:
> On 06/29/2010 01:32 PM, Jan Kiszka wrote:

> Correctness is more important than performance.  Since we don't know 
> whether the guest needs it or not, we have to enable it.  The user may 
> disable it if he likes.

Can't this code only be enabled if VT-d hardware is detected that does
not support the snoop force bit? So the user does not have to struggle
with configuration options that are hard to understand for a
non-developer.

	Joerg