From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [PATCH 5/5] Fix kdump under KVM.
Date: Fri, 30 Oct 2009 20:21:31 -0200
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Cc: Chris Lalancette <clalance@redhat.com>, kvm@vger.kernel.org,
	Avi Kivity <avi@redhat.com>
To: "David S. Ahern" <daahern@cisco.com>
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On Fri, Oct 30, 2009 at 12:03:20PM -0600, David S. Ahern wrote:
> 
> On 10/30/2009 09:28 AM, Chris Lalancette wrote:
> >>
> >> For VMX, the guests TSC's are now usually synchronized (which was not
> >> the case before, when this patch was written). For AMD, they start out
> >> of sync.
> >>
> >> Migration also causes them to be out of sync. So i'd prefer to postpone
> >> the removal of this limitation until there is a guarantee the TSCs 
> >> are synchronized across vcpus.
> > 
> > OK.  I'll try to get on an unsynchronized TSC machine and see if I can reproduce
> > there.
> 
> Perhaps Marcelo was referring to his patchset from December 2008
> targeting TSC synchronization?
> 
> http://www.mail-archive.com/kvm@vger.kernel.org/msg08071.html
> 
> David

Yes, unsynchronized TSCs in the guest perspective.