Subject: Re: [PATCH v16 9/9] arm64: Add kvm capability check extension for ptp_kvm

From: Marc Zyngier <[email-masked]>
Date: Tue, 02 Feb 2021 13:44:47 +0000

On 2020-12-09 06:09, Jianyong Wu wrote:
> Let userspace check if there is kvm ptp service in host.
> Before VMs migrate to another host, VMM may check if this
> cap is available to determine the next behavior.
> 
> Signed-off-by: Jianyong Wu <[email-masked]>
> Suggested-by: Marc Zyngier <[email-masked]>
> ---
>  arch/arm64/kvm/arm.c     | 1 +
>  include/uapi/linux/kvm.h | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
> index f60f4a5e1a22..1bb1f64f9bb5 100644
> --- a/arch/arm64/kvm/arm.c
> +++ b/arch/arm64/kvm/arm.c
> @@ -199,6 +199,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, 
> long ext)
>  	case KVM_CAP_ARM_INJECT_EXT_DABT:
>  	case KVM_CAP_SET_GUEST_DEBUG:
>  	case KVM_CAP_VCPU_ATTRIBUTES:
> +	case KVM_CAP_PTP_KVM:
>  		r = 1;
>  		break;
>  	case KVM_CAP_ARM_SET_DEVICE_ADDR:
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index ca41220b40b8..797c40bbc31f 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1053,6 +1053,7 @@ struct kvm_ppc_resize_hpt {
>  #define KVM_CAP_X86_USER_SPACE_MSR 188
>  #define KVM_CAP_X86_MSR_FILTER 189
>  #define KVM_CAP_ENFORCE_PV_FEATURE_CPUID 190
> +#define KVM_CAP_PTP_KVM 191
> 
>  #ifdef KVM_CAP_IRQ_ROUTING

This really should be squashed with the patch implementing
the hypercall.

Thanks,

         M.
-- 
Jazz is not dead. It just smells funny...