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From:   Kechen Lu <kechenl@nvidia.com>
To:     Greg KH <gregkh@linuxfoundation.org>
CC:     "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        "seanjc@google.com" <seanjc@google.com>,
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Subject: RE: [RFC PATCH v6 1/6] KVM: x86: only allow exits disable before
 vCPUs created
Thread-Topic: [RFC PATCH v6 1/6] KVM: x86: only allow exits disable before
 vCPUs created
Thread-Index: AQHZLT0752AEQSVew0mY9wO2FUfPXq6oeU0AgAExd+A=
Date:   Sun, 22 Jan 2023 01:48:35 +0000
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References: <20230121020738.2973-1-kechenl@nvidia.com>
 <20230121020738.2973-2-kechenl@nvidia.com> <Y8uUAFv9Qz7GvSei@kroah.com>
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Hi Greg,

> -----Original Message-----
> From: Greg KH <gregkh@linuxfoundation.org>
> Sent: Friday, January 20, 2023 11:28 PM
> To: Kechen Lu <kechenl@nvidia.com>
> Cc: kvm@vger.kernel.org; seanjc@google.com; pbonzini@redhat.com;
> zhi.wang.linux@gmail.com; chao.gao@intel.com; shaoqin.huang@intel.com;
> vkuznets@redhat.com; linux-kernel@vger.kernel.org;
> stable@vger.kernel.org
> Subject: Re: [RFC PATCH v6 1/6] KVM: x86: only allow exits disable before
> vCPUs created
>=20
> External email: Use caution opening links or attachments
>=20
>=20
> On Sat, Jan 21, 2023 at 02:07:33AM +0000, Kechen Lu wrote:
> > From: Sean Christopherson <seanjc@google.com>
> >
> > Since VMX and SVM both would never update the control bits if exits
> > are disable after vCPUs are created, only allow setting exits disable
> > flag before vCPU creation.
> >
> > Fixes: 4d5422cea3b6 ("KVM: X86: Provide a capability to disable MWAIT
> > intercepts")
> >
> > Signed-off-by: Sean Christopherson <seanjc@google.com>
>=20
> Nit, no blank line between fixes and signed-off-by please.

Ack.

>=20
> And an RFC on v6?  An RFC usually means "I don't think this is correct so=
 do
> not take it".  How can you do that for 6 versions?  And know that no one =
will
> take an RFC series for that reason (or at least I will
> not...)

Thanks for correcting this, this is my bad. The v2 to v4 revisions, there a=
re big changes=20
on the following patches after this prerequisite patch, so I still "RFC" fo=
r the design.
But I should drop the "RFC" starting from v5, there are already consensus o=
n the v5 design=20
options

Best Regards,
Kechen

>=20
> thanks,
>=20
> greg k-h