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Subject: Re: [Xen-devel] [PATCH][v9 4/6] xen/hvm: Xen PV extension of HVM
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From: Ian Campbell <Ian.Campbell@citrix.com>
To: Jeremy Fitzhardinge <jeremy@goop.org>
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On Tue, 2010-03-16 at 17:12 +0000, Jeremy Fitzhardinge wrote:
> If we need a new vcpuop to make it work 
> properly anyway (set tsc offset), then the presence of that should be
> a 
> good indicator.  In other words, make it depend on its actual fixed 
> pre-reqs, rather than a specific flag for the feature. 

I don't think a new hypercall is required. Xen should simply pre-account
for the TSC offset which HVM guests are subject to in
__update_vcpu_system_time.

Ian.