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From:   Dexuan Cui <decui@microsoft.com>
To:     Thomas Gleixner <tglx@linutronix.de>
CC:     Haiyang Zhang <haiyangz@microsoft.com>,
        KY Srinivasan <kys@microsoft.com>,
        Stephen Hemminger <sthemmin@microsoft.com>,
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        Ingo Molnar <mingo@kernel.org>,
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        "apw@canonical.com" <apw@canonical.com>,
        "jasowang@redhat.com" <jasowang@redhat.com>
Subject: RE: [PATCH] x86/hyper-v: Zero out the VP assist page to fix CPU
 offlining
Thread-Topic: [PATCH] x86/hyper-v: Zero out the VP assist page to fix CPU
 offlining
Thread-Index: AdUyCb6p1/Ch6raqSV2uCwYf/NBGWgK6h7yAAAMgE9AADYqTAAAAYumQAAGMtAAAADPgAA==
Date:   Thu, 18 Jul 2019 08:04:38 +0000
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> From: Thomas Gleixner <tglx@linutronix.de>
> Sent: Thursday, July 18, 2019 12:56 AM
> To: Dexuan Cui <decui@microsoft.com>
>=20
> On Thu, 18 Jul 2019, Dexuan Cui wrote:
> >
> > The concept of the "overlay page" seems weird, and frankly speaking,
> > I don't really understand why the Hyper-V guys invented it, but as far
> > as this patch here is concerned, I think the patch is safe and it can
> > indeed fix the CPU offlining issue I described.
>=20
> Then this needs some really good explanation and in the change log becaus=
e
> that's really obscure behaviour.
>=20
> 	tglx

Agreed. I'll combine my replies into the changelog and post a v2 of
the one-line patch.

Thanks,
-- Dexuan