From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Roedel, Joerg" <Joerg.Roedel@amd.com>
Subject: Re: [PATCH] kvm/fpu: Enable fully eager restore kvm FPU
Date: Mon, 20 Aug 2012 12:53:45 +0200
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Cc: "Hao, Xudong" <xudong.hao@intel.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	"Zhang, Xiantao" <xiantao.zhang@intel.com>
To: Avi Kivity <avi@redhat.com>
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On Mon, Aug 20, 2012 at 01:43:10PM +0300, Avi Kivity wrote:
> On 08/20/2012 01:14 PM, Roedel, Joerg wrote:
> > On Mon, Aug 20, 2012 at 01:08:14PM +0300, Avi Kivity wrote:
> >> On 08/20/2012 12:24 PM, Roedel, Joerg wrote:
> > 
> >> So it was broken all along?  Yikes.
> > 
> > There is no LWP support in the kernel and thus KVM can't expose it to
> > guests. So for now nothing should be broken, no?
> 
> Oh, we mask out xcr0 bits not supported by the host.
> 
> So it's broken in another way: it isn't exposed.  Pity, it's such a nice
> feature.

Right, that is very sad. We can support it in KVM even without Linux
host support, but there is no OS which enables this feature yet, so it
is rather useless to do it in KVM only.


	Joerg