[PATCH v1 1/2] s390x: KVM: accept STSI for CPU topology information

[Pierre Morel <pmorel@linux.ibm.com>]

STSI(15.1.x) gives information on the CPU configuration topology.
Let's accept the interception of STSI with the function code 15 and
let the userland part of the hypervisor handle it.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
---
 arch/s390/kvm/priv.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index 9928f785c677..4ab5f8b7780e 100644
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -856,7 +856,7 @@ static int handle_stsi(struct kvm_vcpu *vcpu)
 	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
 		return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
 
-	if (fc > 3) {
+	if (fc > 3 && fc != 15) {
 		kvm_s390_set_psw_cc(vcpu, 3);
 		return 0;
 	}
@@ -893,6 +893,15 @@ static int handle_stsi(struct kvm_vcpu *vcpu)
 			goto out_no_data;
 		handle_stsi_3_2_2(vcpu, (void *) mem);
 		break;
+	case 15:
+		if (sel1 != 1 || sel2 < 2 || sel2 > 6)
+			goto out_no_data;
+		if (vcpu->kvm->arch.user_stsi) {
+			insert_stsi_usr_data(vcpu, operand2, ar, fc, sel1, sel2);
+			return -EREMOTE;
+		}
+		kvm_s390_set_psw_cc(vcpu, 3);
+		return 0;
 	}
 	if (kvm_s390_pv_cpu_is_protected(vcpu)) {
 		memcpy((void *)sida_origin(vcpu->arch.sie_block), (void *)mem,
-- 
2.25.1