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From:   Jianyong Wu <Jianyong.Wu@arm.com>
To:     Marc Zyngier <maz@kernel.org>
CC:     "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
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        Mark Rutland <Mark.Rutland@arm.com>,
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        Suzuki Poulose <Suzuki.Poulose@arm.com>,
        Steven Price <Steven.Price@arm.com>,
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        Steve Capper <Steve.Capper@arm.com>,
        Justin He <Justin.He@arm.com>, nd <nd@arm.com>
Subject: RE: [PATCH v14 07/10] arm64/kvm: Add hypercall service for kvm ptp.
Thread-Topic: [PATCH v14 07/10] arm64/kvm: Add hypercall service for kvm ptp.
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Date:   Mon, 7 Sep 2020 08:13:11 +0000
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Hi Marc,

> -----Original Message-----
> From: Marc Zyngier <maz@kernel.org>
> Sent: Saturday, September 5, 2020 7:04 PM
> To: Jianyong Wu <Jianyong.Wu@arm.com>
> Cc: netdev@vger.kernel.org; yangbo.lu@nxp.com; john.stultz@linaro.org;
> tglx@linutronix.de; pbonzini@redhat.com; sean.j.christopherson@intel.com;
> richardcochran@gmail.com; Mark Rutland <Mark.Rutland@arm.com>;
> will@kernel.org; Suzuki Poulose <Suzuki.Poulose@arm.com>; Steven Price
> <Steven.Price@arm.com>; linux-kernel@vger.kernel.org; linux-arm-
> kernel@lists.infradead.org; kvmarm@lists.cs.columbia.edu;
> kvm@vger.kernel.org; Steve Capper <Steve.Capper@arm.com>; Justin He
> <Justin.He@arm.com>; nd <nd@arm.com>
> Subject: Re: [PATCH v14 07/10] arm64/kvm: Add hypercall service for kvm
> ptp.
>=20
> On Fri, 04 Sep 2020 10:27:41 +0100,
> Jianyong Wu <jianyong.wu@arm.com> wrote:
> >
> > ptp_kvm will get this service through smccc call.
> > The service offers wall time and counter cycle of host for guest.
> > caller must explicitly determines which cycle of virtual counter or
> > physical counter to return if it needs counter cycle.
> >
> > Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
> > ---
> >  arch/arm64/kvm/Kconfig       |  6 +++++
> >  arch/arm64/kvm/arch_timer.c  |  2 +-
> >  arch/arm64/kvm/hypercalls.c  | 49
> > ++++++++++++++++++++++++++++++++++++
> >  include/kvm/arm_arch_timer.h |  1 +
> >  include/linux/arm-smccc.h    | 16 ++++++++++++
> >  5 files changed, 73 insertions(+), 1 deletion(-)
> >
>=20
> [...]
>=20
> On top of what I said yesterday:
>=20
> > index 32ba6fbc3814..eb85f6701845 100644
> > --- a/arch/arm64/kvm/arch_timer.c
> > +++ b/arch/arm64/kvm/arch_timer.c
> > @@ -81,7 +81,7 @@ u64 timer_get_cval(struct arch_timer_context *ctxt)
> >  	}
> >  }
> >
> > -static u64 timer_get_offset(struct arch_timer_context *ctxt)
> > +u64 timer_get_offset(struct arch_timer_context *ctxt)
> >  {
> >  	struct kvm_vcpu *vcpu =3D ctxt->vcpu;
> >
>=20
> Why has this become global? I can't see a reason why we would want to
> expose this purely KVM internal helper.
>=20
Sorry to have forgotten remove this change.

Thanks
Jianyong=20
> 	M.
>=20
> --
> Without deviation from the norm, progress is not possible.