From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gerd Hoffmann <kraxel@redhat.com>
Subject: Re: Userspace MSR handling
Date: Mon, 25 May 2009 13:03:48 +0200
Message-ID: <4A1A7B14.5000205@redhat.com>
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Cc: Alexander Graf <agraf@suse.de>,
	Ed Swierk <eswierk@aristanetworks.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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On 05/24/09 14:07, Avi Kivity wrote:
> I agree however that the Xen hypercall page protocol has no business in
> kvm.ko. But can't we implement it in emu? Xenner conveniently places a
> ring 0 stub in the guest, we could trap the MSR there and emulate it
> entirely in the guest.

No.  The case where handling the msr writes is needed is the pv-on-hvm 
driver support.  For pv kernels it could be handled by emu if it would 
be needed, but pv kernels don't need the msr stuff in the first place. 
There should be a longish mail about that in the list archive ...

cheers,
   Gerd