> int kvm_s390_handle_diag(struct kvm_vcpu *vcpu)
> {
> int code = kvm_s390_get_base_disp_rs(vcpu, NULL) & 0xffff;
> @@ -254,6 +268,8 @@ int kvm_s390_handle_diag(struct kvm_vcpu *vcpu)
> return __diag_page_ref_service(vcpu);
> case 0x308:
> return __diag_ipl_functions(vcpu);
> + case 0x318:
> + return __diag_set_control_prog_name(vcpu);
> case 0x500:
> return __diag_virtio_hypercall(vcpu);
> default:
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index 91ad4a9..678c9cb 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -156,6 +156,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
> { "instruction_diag_9c", VCPU_STAT(diagnose_9c) },
> { "instruction_diag_258", VCPU_STAT(diagnose_258) },
> { "instruction_diag_308", VCPU_STAT(diagnose_308) },
> + { "instruction_diag_318", VCPU_STAT(diagnose_318) },
> { "instruction_diag_500", VCPU_STAT(diagnose_500) },
> { "instruction_diag_other", VCPU_STAT(diagnose_other) },
> { NULL }
> @@ -370,6 +371,10 @@ static void kvm_s390_cpu_feat_init(void)
>
> if (MACHINE_HAS_ESOP)
> allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP);
> +
> + /* Always allow diag318 for a guest */
> + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_DIAG318);
So DIAG 318 emulation can always be provided. But how are we to handle
if we have SIE support for CPNC or not? Shouldn't that also being taken
into account?
When do we have SIE support? Does that come with DIAG318 itself? How to
check?
Also, I guess we should not allow access to the cnpc value if we don't
have SIE support (read+write).
> +
> /*
> * We need SIE support, ESOP (PROT_READ protection for gmap_shadow),
> * 64bit SCAO (SCA passthrough) and IDTE (for gmap_shadow unshadowing).
> @@ -1140,6 +1145,72 @@ static int kvm_s390_get_tod(struct kvm *kvm, struct kvm_device_attr *attr)
> return ret;
> }
>
> +void kvm_s390_set_cpc(struct kvm *kvm, u64 cpc)
> +{
> + struct kvm_vcpu *vcpu;
> + int i;
> +
> + mutex_lock(&kvm->lock);
> + kvm->arch.cpnc = cpc >> 56;
> + kvm->arch.cpvc = cpc & 0x00ffffffffffffffUL;
> +
> + VM_EVENT(kvm, 3, "SET: CPNC: 0x%x CPVC: 0x%llx",
> + kvm->arch.cpnc, kvm->arch.cpvc);
> +
> + kvm_for_each_vcpu(i, vcpu, kvm) {
> + vcpu->arch.sie_block->cpnc = kvm->arch.cpnc;
> + }
I guess the right thing to do is a synchronous all-VCPU request. Let
them then update it themselves when handling the request. (this can
effectively be called while other VCPUs are already executing)
As an alternative, block/unblock all VCPUs, but I guess a request is the
easiest and cleanest way.
> + mutex_unlock(&kvm->lock);
> +}
> +
> +static int kvm_s390_set_misc(struct kvm *kvm, struct kvm_device_attr *attr)
> +{
> + int ret;
> + u64 cpc;
> +
> + switch (attr->attr) {
> + case KVM_S390_VM_MISC_CPC:
> + ret = -EFAULT;
> + if (get_user(cpc, (u64 __user *)attr->addr))
> + break;
> + kvm_s390_set_cpc(kvm, cpc);
> + ret = 0;
> + break;
> + default:
> + ret = -ENXIO;
> + break;
> + }
> + return ret;
> +}
--
Thanks,
David / dhildenb
