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Re: [Xen-devel] write_tsc in a PV domain?

To: Dan Magenheimer <dan.magenheimer@xxxxxxxxxx>
Subject: Re: [Xen-devel] write_tsc in a PV domain?
From: Chris Lalancette <clalance@xxxxxxxxxx>
Date: Thu, 27 Aug 2009 10:39:40 +0200
Cc: Jeremy Fitzhardinge <jeremy@xxxxxxxx>, "Xen-Devel \(E-mail\)" <xen-devel@xxxxxxxxxxxxxxxxxxx>, Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
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Dan Magenheimer wrote:
> In that case, are you saying it is an illegal instruction for a PV
> guest to execute?  If so, we should not ignore it, we should fail
> the guest.  But that would be unfortunate for the RHEL5-64bit
> PV guests that actually DO use it.

Wait, what?  Could you point out where this is in RHEL-5 64-bit PV?  The only
case of write_tsc() I see in the code is in arch/i386/kernel/smpboot.c, which is
not used by the Xen PV implementation in RHEL-5.  Where else in the PV
implementation does a write_tsc?

Chris Lalancette

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