Re: [PATCH v6 25/27] KVM: arm64: Add a capability to advertise SVE support

[Julien Thierry <julien.thierry@arm.com>]

Hi Dave,

On 19/03/2019 17:52, Dave Martin wrote:
> To provide a uniform way to check for KVM SVE support amongst other
> features, this patch adds a suitable capability KVM_CAP_ARM_SVE,
> and reports it as present when SVE is available.
> 
> Signed-off-by: Dave Martin <Dave.Martin@arm.com>
> 

Reviewed-by: Julien Thierry <julien.thierry@arm.com>

Cheers,

Julien

> ---
> 
> Changes since v5:
> 
>  * [Julien Thierry] Strip out has_vhe() sanity-check, which wasn't in
>    the most logical place, and anyway doesn't really belong in this
>    patch.
> 
>    Moved to KVM: arm64/sve: Allow userspace to enable SVE for vcpus
>    instead.
> ---
>  arch/arm64/kvm/reset.c   | 3 +++
>  include/uapi/linux/kvm.h | 1 +
>  2 files changed, 4 insertions(+)
> 
> diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
> index 4f04dbf..180d7a5 100644
> --- a/arch/arm64/kvm/reset.c
> +++ b/arch/arm64/kvm/reset.c
> @@ -98,6 +98,9 @@ int kvm_arch_vm_ioctl_check_extension(struct kvm *kvm, long ext)
>  	case KVM_CAP_ARM_VM_IPA_SIZE:
>  		r = kvm_ipa_limit;
>  		break;
> +	case KVM_CAP_ARM_SVE:
> +		r = system_supports_sve();
> +		break;
>  	default:
>  		r = 0;
>  	}
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index c3b8e7a..1d56444 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -988,6 +988,7 @@ struct kvm_ppc_resize_hpt {
>  #define KVM_CAP_ARM_VM_IPA_SIZE 165
>  #define KVM_CAP_MANUAL_DIRTY_LOG_PROTECT 166
>  #define KVM_CAP_HYPERV_CPUID 167
> +#define KVM_CAP_ARM_SVE 168
>  
>  #ifdef KVM_CAP_IRQ_ROUTING
>  
> 

-- 
Julien Thierry