Re: [PATCH v14 07/10] arm64/kvm: Add hypercall service for kvm ptp.

From: Marc Zyngier
Date: Sat Sep 05 2020 - 07:04:19 EST


On Fri, 04 Sep 2020 10:27:41 +0100,
Jianyong Wu <jianyong.wu@xxxxxxx> 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@xxxxxxx>
> ---
> 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(-)
>

[...]

On top of what I said yesterday:

> 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 = ctxt->vcpu;
>

Why has this become global? I can't see a reason why we would want to
expose this purely KVM internal helper.

M.

--
Without deviation from the norm, progress is not possible.