From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: [PATCH v11 2/3] x86, apicv: add virtual x2apic support
Date: Tue, 22 Jan 2013 11:42:44 +0200
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Cc: Yang Zhang <yang.z.zhang@intel.com>, kvm@vger.kernel.org,
	haitao.shan@intel.com, xiantao.zhang@intel.com,
	Kevin Tian <kevin.tian@intel.com>
To: Marcelo Tosatti <mtosatti@redhat.com>
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On Mon, Jan 21, 2013 at 08:16:18PM -0200, Marcelo Tosatti wrote:
> On Mon, Jan 21, 2013 at 11:34:20PM +0200, Gleb Natapov wrote:
> > On Mon, Jan 21, 2013 at 07:21:13PM -0200, Marcelo Tosatti wrote:
> > > On Mon, Jan 21, 2013 at 10:21:14PM +0200, Gleb Natapov wrote:
> > > > > >  	}
> > > > > > +
> > > > > > +	vcpu->arch.apic_base = value;
> > > > > 
> > > > > Simpler to have
> > > > > 
> > > > > if (apic_x2apic_mode(apic)) {
> > > > > 	...
> > > > > 	kvm_x86_ops->set_virtual_x2apic_mode(vcpu, true);
> > > > > } else {
> > > > > 	kvm_x86_ops->set_virtual_x2apic_mode(vcpu, false);
> > > > > }
> > > > > 
> > > > This will not work during cpu init. That was discussed on one of
> > > > the previous iterations of the patch. When this code is called during
> > > > vcpu init vmcs is not loaded yet so set_virtual_x2apic_mode() cannot
> > > > write into it.
> > > 
> > > Are you saying that the logic to write on bit value change is due to 
> > > ordering with cpu init or that the callback is at the wrong place?
> > > 
> > The logic is because of ordering with cpu init.
> 
> OK. Still must move this conditional callback after assignment of apic_base.
> 
Sure.

--
			Gleb.