Re: [PATCH v2 29/30] KVM: s390: introduce CPU feature for zPCI Interpretation

[Pierre Morel]

On 1/14/22 21:31, Matthew Rosato wrote:
> KVM_S390_VM_CPU_FEAT_ZPCI_INTERP relays whether zPCI interpretive
> execution is possible based on the available hardware facilities.
>
> Signed-off-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
> ---
>   arch/s390/include/uapi/asm/kvm.h | 1 +
>   arch/s390/kvm/kvm-s390.c         | 4 ++++
>   2 files changed, 5 insertions(+)
>
> diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
> index 7a6b14874d65..ed06458a871f 100644
> --- a/arch/s390/include/uapi/asm/kvm.h
> +++ b/arch/s390/include/uapi/asm/kvm.h
> @@ -130,6 +130,7 @@ struct kvm_s390_vm_cpu_machine {
>   #define KVM_S390_VM_CPU_FEAT_PFMFI	11
>   #define KVM_S390_VM_CPU_FEAT_SIGPIF	12
>   #define KVM_S390_VM_CPU_FEAT_KSS	13
> +#define KVM_S390_VM_CPU_FEAT_ZPCI_INTERP 14
>   struct kvm_s390_vm_cpu_feat {
>   	__u64 feat[16];
>   };
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index b6c32fc3b272..3ed59fe512dd 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -434,6 +434,10 @@ static void kvm_s390_cpu_feat_init(void)
>   	if (test_facility(151)) /* DFLTCC */
>   		__insn32_query(INSN_DFLTCC, kvm_s390_available_subfunc.dfltcc);
>   
> +	if (test_facility(69) && test_facility(70) && test_facility(71) &&
> +	    test_facility(72)) /* zPCI Interpretation */
> +		allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ZPCI_INTERP);
> +

Don't we want to start the support of ZPCI interpretation starting with 
Z14 ?

>   	if (MACHINE_HAS_ESOP)
>   		allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP);
>   	/*

--
Pierre Morel
IBM Lab Boeblingen