6 files changed, 91 insertions, 5 deletions

diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index 147b87f..a0b586c 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -272,6 +272,8 @@ static int handle_external_interrupt(struct kvm_vcpu *vcpu)
 		irq.type = KVM_S390_INT_CPU_TIMER;
 		break;
 	case EXT_IRQ_EXTERNAL_CALL:
+		if (kvm_s390_si_ext_call_pending(vcpu))
+			return 0;
 		irq.type = KVM_S390_INT_EXTERNAL_CALL;
 		irq.parm = vcpu->arch.sie_block->extcpuaddr;
 		break;
@@ -323,6 +325,8 @@ static int handle_partial_execution(struct kvm_vcpu *vcpu)
 {
 	if (vcpu->arch.sie_block->ipa == 0xb254)	/* MVPG */
 		return handle_mvpg_pei(vcpu);
+	if (vcpu->arch.sie_block->ipa >> 8 == 0xae)	/* SIGP */
+		return kvm_s390_handle_sigp_pei(vcpu);
 
 	return -EOPNOTSUPP;
 }
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 75cd321..bf0d9bc 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -148,9 +148,8 @@ static void __unset_cpu_idle(struct kvm_vcpu *vcpu)
 
 static void __reset_intercept_indicators(struct kvm_vcpu *vcpu)
 {
-	atomic_clear_mask(CPUSTAT_ECALL_PEND |
-		CPUSTAT_IO_INT | CPUSTAT_EXT_INT | CPUSTAT_STOP_INT,
-		&vcpu->arch.sie_block->cpuflags);
+	atomic_clear_mask(CPUSTAT_IO_INT | CPUSTAT_EXT_INT | CPUSTAT_STOP_INT,
+			  &vcpu->arch.sie_block->cpuflags);
 	vcpu->arch.sie_block->lctl = 0x0000;
 	vcpu->arch.sie_block->ictl &= ~(ICTL_LPSW | ICTL_STCTL | ICTL_PINT);
 
@@ -524,6 +523,20 @@ static void deliver_ckc_interrupt(struct kvm_vcpu *vcpu)
 	}
 }
 
+/* Check whether SIGP interpretation facility has an external call pending */
+int kvm_s390_si_ext_call_pending(struct kvm_vcpu *vcpu)
+{
+	atomic_t *sigp_ctrl = &vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].ctrl;
+
+	if (!psw_extint_disabled(vcpu) &&
+	    (vcpu->arch.sie_block->gcr[0] & 0x2000ul) &&
+	    (atomic_read(sigp_ctrl) & SIGP_CTRL_C) &&
+	    (atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_ECALL_PEND))
+		return 1;
+
+	return 0;
+}
+
 int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
 {
 	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
@@ -554,6 +567,9 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
 	if (!rc && kvm_cpu_has_pending_timer(vcpu))
 		rc = 1;
 
+	if (!rc && kvm_s390_si_ext_call_pending(vcpu))
+		rc = 1;
+
 	return rc;
 }
 
@@ -610,7 +626,8 @@ no_timer:
 	while (list_empty(&vcpu->arch.local_int.list) &&
 		list_empty(&vcpu->arch.local_int.float_int->list) &&
 		(!vcpu->arch.local_int.timer_due) &&
-		!signal_pending(current)) {
+		!signal_pending(current) &&
+		!kvm_s390_si_ext_call_pending(vcpu)) {
 		set_current_state(TASK_INTERRUPTIBLE);
 		spin_unlock_bh(&vcpu->arch.local_int.lock);
 		spin_unlock(&vcpu->arch.local_int.float_int->lock);
@@ -667,6 +684,11 @@ void kvm_s390_clear_local_irqs(struct kvm_vcpu *vcpu)
 	}
 	atomic_set(&li->active, 0);
 	spin_unlock_bh(&li->lock);
+
+	/* clear pending external calls set by sigp interpretation facility */
+	atomic_clear_mask(CPUSTAT_ECALL_PEND, &vcpu->arch.sie_block->cpuflags);
+	atomic_clear_mask(SIGP_CTRL_C,
+			  &vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].ctrl);
 }
 
 void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index d91feb2..2c24312 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -633,7 +633,7 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
 		vcpu->arch.sie_block->ecb |= 0x10;
 
 	vcpu->arch.sie_block->ecb2  = 8;
-	vcpu->arch.sie_block->eca   = 0xC1002000U;
+	vcpu->arch.sie_block->eca   = 0xD1002000U;
 	if (sclp_has_siif())
 		vcpu->arch.sie_block->eca |= 1;
 	vcpu->arch.sie_block->fac   = (int) (long) vfacilities;
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index e489945..87edfc9 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -154,6 +154,7 @@ int kvm_s390_handle_eb(struct kvm_vcpu *vcpu);
 
 /* implemented in sigp.c */
 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu);
+int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu);
 
 /* implemented in kvm-s390.c */
 long kvm_arch_fault_in_page(struct kvm_vcpu *vcpu, gpa_t gpa, int writable);
@@ -214,6 +215,7 @@ static inline int kvm_s390_inject_prog_cond(struct kvm_vcpu *vcpu, int rc)
 int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu);
 int psw_extint_disabled(struct kvm_vcpu *vcpu);
 void kvm_s390_destroy_adapters(struct kvm *kvm);
+int kvm_s390_si_ext_call_pending(struct kvm_vcpu *vcpu);
 
 /* implemented in guestdbg.c */
 void kvm_s390_backup_guest_per_regs(struct kvm_vcpu *vcpu);
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index c0b99e0..d0341d2 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -458,3 +458,38 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 	kvm_s390_set_psw_cc(vcpu, rc);
 	return 0;
 }
+
+/*
+ * Handle SIGP partial execution interception.
+ *
+ * This interception will occur at the source cpu when a source cpu sends an
+ * external call to a target cpu and the target cpu has the WAIT bit set in
+ * its cpuflags. Interception will occurr after the interrupt indicator bits at
+ * the target cpu have been set. All error cases will lead to instruction
+ * interception, therefore nothing is to be checked or prepared.
+ */
+int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu)
+{
+	int r3 = vcpu->arch.sie_block->ipa & 0x000f;
+	u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
+	struct kvm_vcpu *dest_vcpu;
+	u8 order_code = kvm_s390_get_base_disp_rs(vcpu);
+
+	trace_kvm_s390_handle_sigp_pei(vcpu, order_code, cpu_addr);
+
+	if (order_code == SIGP_EXTERNAL_CALL) {
+		dest_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
+		BUG_ON(dest_vcpu == NULL);
+
+		spin_lock_bh(&dest_vcpu->arch.local_int.lock);
+		if (waitqueue_active(&dest_vcpu->wq))
+			wake_up_interruptible(&dest_vcpu->wq);
+		dest_vcpu->preempted = true;
+		spin_unlock_bh(&dest_vcpu->arch.local_int.lock);
+
+		kvm_s390_set_psw_cc(vcpu, SIGP_CC_ORDER_CODE_ACCEPTED);
+		return 0;
+	}
+
+	return -EOPNOTSUPP;
+}
diff --git a/arch/s390/kvm/trace.h b/arch/s390/kvm/trace.h
index 579b42a..916834d 100644
--- a/arch/s390/kvm/trace.h
+++ b/arch/s390/kvm/trace.h
@@ -239,6 +239,29 @@ TRACE_EVENT(kvm_s390_handle_sigp,
 			   __entry->cpu_addr, __entry->parameter)
 	);
 
+TRACE_EVENT(kvm_s390_handle_sigp_pei,
+	    TP_PROTO(VCPU_PROTO_COMMON, __u8 order_code, __u16 cpu_addr),
+	    TP_ARGS(VCPU_ARGS_COMMON, order_code, cpu_addr),
+
+	    TP_STRUCT__entry(
+		    VCPU_FIELD_COMMON
+		    __field(__u8, order_code)
+		    __field(__u16, cpu_addr)
+		    ),
+
+	    TP_fast_assign(
+		    VCPU_ASSIGN_COMMON
+		    __entry->order_code = order_code;
+		    __entry->cpu_addr = cpu_addr;
+		    ),
+
+	    VCPU_TP_PRINTK("handle sigp pei order %02x (%s), cpu address %04x",
+			   __entry->order_code,
+			   __print_symbolic(__entry->order_code,
+					    sigp_order_codes),
+			   __entry->cpu_addr)
+	);
+
 TRACE_EVENT(kvm_s390_handle_diag,
 	    TP_PROTO(VCPU_PROTO_COMMON, __u16 code),
 	    TP_ARGS(VCPU_ARGS_COMMON, code),