Re: [PATCH] LoongArch: KVM: Add some feature detection on host with 3C6000

[Yanteng Si <si.yanteng@linux.dev>]

在 7/7/25 11:51 AM, Bibo Mao 写道:
> With 3C6000 hardware platform, hardware page table walking and avec
> features are supported on host. Here add these two feature detection
> on KVM host.
> 
> Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Yanteng Si <siyanteng@cqsoftware.com.cn>

Thanks,
Yanteng
> ---
>   arch/loongarch/include/uapi/asm/kvm.h | 2 ++
>   arch/loongarch/kvm/vm.c               | 8 ++++++++
>   2 files changed, 10 insertions(+)
> 
> diff --git a/arch/loongarch/include/uapi/asm/kvm.h b/arch/loongarch/include/uapi/asm/kvm.h
> index 5f354f5c6847..0b9feb6c0d53 100644
> --- a/arch/loongarch/include/uapi/asm/kvm.h
> +++ b/arch/loongarch/include/uapi/asm/kvm.h
> @@ -103,6 +103,8 @@ struct kvm_fpu {
>   #define  KVM_LOONGARCH_VM_FEAT_PMU		5
>   #define  KVM_LOONGARCH_VM_FEAT_PV_IPI		6
>   #define  KVM_LOONGARCH_VM_FEAT_PV_STEALTIME	7
> +#define  KVM_LOONGARCH_VM_FEAT_PTW		8
> +#define  KVM_LOONGARCH_VM_FEAT_AVEC		9
>   
>   /* Device Control API on vcpu fd */
>   #define KVM_LOONGARCH_VCPU_CPUCFG	0
> diff --git a/arch/loongarch/kvm/vm.c b/arch/loongarch/kvm/vm.c
> index edccfc8c9cd8..728b24a62f1e 100644
> --- a/arch/loongarch/kvm/vm.c
> +++ b/arch/loongarch/kvm/vm.c
> @@ -146,6 +146,14 @@ static int kvm_vm_feature_has_attr(struct kvm *kvm, struct kvm_device_attr *attr
>   		if (kvm_pvtime_supported())
>   			return 0;
>   		return -ENXIO;
> +	case KVM_LOONGARCH_VM_FEAT_PTW:
> +		if (cpu_has_ptw)
> +			return 0;
> +		return -ENXIO;
> +	case KVM_LOONGARCH_VM_FEAT_AVEC:
> +		if (cpu_has_avecint)
> +			return 0;
> +		return -ENXIO;
>   	default:
>   		return -ENXIO;
>   	}