From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [Qemu-devel] [PATCHv4 3/4] cpuid: disable pv eoi for 1.1 and
 older compat types
Date: Wed, 29 Aug 2012 13:31:13 +0300
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On Wed, Aug 29, 2012 at 01:23:24PM +0300, Michael S. Tsirkin wrote:
> > Michael, not migrating the PVEOI MSR actually crashes the guest?
> 
> 
> Not at all. migration currently simply disables PV EOI, so
> each EOI triggers exits after migration.

I would like to add: without this patch guest will crash.
But what will crash guest is *not* the fact
we do not migrate the PV EOI MSR.
It is the fact that PV EOI bit is set in CPUID.
If guest reads CPUID before migration and then
writes the MSR after migration, it will crash.

> -- 
> MST