Re: [PATCH v5 4/7] support user space to query RAS extension feature

[Christoffer Dall <cdall@linaro.org>]

On Fri, Aug 18, 2017 at 10:11:54PM +0800, Dongjiu Geng wrote:

You should put KVM and arm64 in the subject here.

> In armv8.2 RAS extension, it adds virtual SError exception
> syndrome registeri(VSESR_EL2), user space will specify that
> value. so user space will check whether CPU feature has RAS
> extension. if has, it will specify the virtual SError syndrome
> value. Otherwise, it will not set. This patch adds this support
> 
> Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
> ---
>  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 3256b9228e75..b7313ee028e9 100644
> --- a/arch/arm64/kvm/reset.c
> +++ b/arch/arm64/kvm/reset.c
> @@ -77,6 +77,9 @@ int kvm_arch_dev_ioctl_check_extension(struct kvm *kvm, long ext)
>  	case KVM_CAP_ARM_PMU_V3:
>  		r = kvm_arm_support_pmu_v3();
>  		break;
> +	case KVM_CAP_ARM_RAS_EXTENSION:
> +		r = cpus_have_const_cap(ARM64_HAS_RAS_EXTN);
> +		break;
>  	case KVM_CAP_SET_GUEST_DEBUG:
>  	case KVM_CAP_VCPU_ATTRIBUTES:
>  		r = 1;
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 6cd63c18708a..5a2a338cae57 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -929,6 +929,7 @@ struct kvm_ppc_resize_hpt {
>  #define KVM_CAP_PPC_SMT_POSSIBLE 147
>  #define KVM_CAP_HYPERV_SYNIC2 148
>  #define KVM_CAP_HYPERV_VP_INDEX 149
> +#define KVM_CAP_ARM_RAS_EXTENSION 150
>  
>  #ifdef KVM_CAP_IRQ_ROUTING
>  
> -- 
> 2.14.0
> 

Thanks,
-Christoffer