7 files changed, 133 insertions, 133 deletions

diff --git a/arch/s390/kvm/Kconfig b/arch/s390/kvm/Kconfig
index 10d529ac9821..646db9c467d1 100644
--- a/arch/s390/kvm/Kconfig
+++ b/arch/s390/kvm/Kconfig
@@ -26,6 +26,7 @@ config KVM
 	select KVM_ASYNC_PF
 	select KVM_ASYNC_PF_SYNC
 	select HAVE_KVM_IRQCHIP
+	select HAVE_KVM_IRQFD
 	select HAVE_KVM_IRQ_ROUTING
 	---help---
 	  Support hosting paravirtualized guest machines using the SIE
diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c
index 0161675878a2..59bd8f991b98 100644
--- a/arch/s390/kvm/diag.c
+++ b/arch/s390/kvm/diag.c
@@ -176,7 +176,8 @@ static int __diag_ipl_functions(struct kvm_vcpu *vcpu)
 		return -EOPNOTSUPP;
 	}
 
-	kvm_s390_vcpu_stop(vcpu);
+	if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm))
+		kvm_s390_vcpu_stop(vcpu);
 	vcpu->run->s390_reset_flags |= KVM_S390_RESET_SUBSYSTEM;
 	vcpu->run->s390_reset_flags |= KVM_S390_RESET_IPL;
 	vcpu->run->s390_reset_flags |= KVM_S390_RESET_CPU_INIT;
diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index a0b586c1913c..eaf46291d361 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -56,32 +56,26 @@ static int handle_noop(struct kvm_vcpu *vcpu)
 static int handle_stop(struct kvm_vcpu *vcpu)
 {
 	int rc = 0;
+	unsigned int action_bits;
 
 	vcpu->stat.exit_stop_request++;
-	spin_lock_bh(&vcpu->arch.local_int.lock);
-
 	trace_kvm_s390_stop_request(vcpu->arch.local_int.action_bits);
 
-	if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP) {
-		kvm_s390_vcpu_stop(vcpu);
-		vcpu->arch.local_int.action_bits &= ~ACTION_STOP_ON_STOP;
-		VCPU_EVENT(vcpu, 3, "%s", "cpu stopped");
-		rc = -EOPNOTSUPP;
-	}
+	action_bits = vcpu->arch.local_int.action_bits;
 
-	if (vcpu->arch.local_int.action_bits & ACTION_STORE_ON_STOP) {
-		vcpu->arch.local_int.action_bits &= ~ACTION_STORE_ON_STOP;
-		/* store status must be called unlocked. Since local_int.lock
-		 * only protects local_int.* and not guest memory we can give
-		 * up the lock here */
-		spin_unlock_bh(&vcpu->arch.local_int.lock);
+	if (!(action_bits & ACTION_STOP_ON_STOP))
+		return 0;
+
+	if (action_bits & ACTION_STORE_ON_STOP) {
 		rc = kvm_s390_vcpu_store_status(vcpu,
 						KVM_S390_STORE_STATUS_NOADDR);
-		if (rc >= 0)
-			rc = -EOPNOTSUPP;
-	} else
-		spin_unlock_bh(&vcpu->arch.local_int.lock);
-	return rc;
+		if (rc)
+			return rc;
+	}
+
+	if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm))
+		kvm_s390_vcpu_stop(vcpu);
+	return -EOPNOTSUPP;
 }
 
 static int handle_validity(struct kvm_vcpu *vcpu)
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 90c8de22a2a0..f4c819bfc193 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -158,6 +158,9 @@ static void __reset_intercept_indicators(struct kvm_vcpu *vcpu)
 					       LCTL_CR10 | LCTL_CR11);
 		vcpu->arch.sie_block->ictl |= (ICTL_STCTL | ICTL_PINT);
 	}
+
+	if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP)
+		atomic_set_mask(CPUSTAT_STOP_INT, &vcpu->arch.sie_block->cpuflags);
 }
 
 static void __set_cpuflag(struct kvm_vcpu *vcpu, u32 flag)
@@ -544,13 +547,13 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
 	int rc = 0;
 
 	if (atomic_read(&li->active)) {
-		spin_lock_bh(&li->lock);
+		spin_lock(&li->lock);
 		list_for_each_entry(inti, &li->list, list)
 			if (__interrupt_is_deliverable(vcpu, inti)) {
 				rc = 1;
 				break;
 			}
-		spin_unlock_bh(&li->lock);
+		spin_unlock(&li->lock);
 	}
 
 	if ((!rc) && atomic_read(&fi->active)) {
@@ -585,88 +588,56 @@ int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
 int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
 {
 	u64 now, sltime;
-	DECLARE_WAITQUEUE(wait, current);
 
 	vcpu->stat.exit_wait_state++;
-	if (kvm_cpu_has_interrupt(vcpu))
-		return 0;
 
-	__set_cpu_idle(vcpu);
-	spin_lock_bh(&vcpu->arch.local_int.lock);
-	vcpu->arch.local_int.timer_due = 0;
-	spin_unlock_bh(&vcpu->arch.local_int.lock);
+	/* fast path */
+	if (kvm_cpu_has_pending_timer(vcpu) || kvm_arch_vcpu_runnable(vcpu))
+		return 0;
 
 	if (psw_interrupts_disabled(vcpu)) {
 		VCPU_EVENT(vcpu, 3, "%s", "disabled wait");
-		__unset_cpu_idle(vcpu);
 		return -EOPNOTSUPP; /* disabled wait */
 	}
 
+	__set_cpu_idle(vcpu);
 	if (!ckc_interrupts_enabled(vcpu)) {
 		VCPU_EVENT(vcpu, 3, "%s", "enabled wait w/o timer");
 		goto no_timer;
 	}
 
 	now = get_tod_clock_fast() + vcpu->arch.sie_block->epoch;
-	if (vcpu->arch.sie_block->ckc < now) {
-		__unset_cpu_idle(vcpu);
-		return 0;
-	}
-
 	sltime = tod_to_ns(vcpu->arch.sie_block->ckc - now);
-
 	hrtimer_start(&vcpu->arch.ckc_timer, ktime_set (0, sltime) , HRTIMER_MODE_REL);
 	VCPU_EVENT(vcpu, 5, "enabled wait via clock comparator: %llx ns", sltime);
 no_timer:
 	srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx);
-	spin_lock(&vcpu->arch.local_int.float_int->lock);
-	spin_lock_bh(&vcpu->arch.local_int.lock);
-	add_wait_queue(&vcpu->wq, &wait);
-	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) &&
-		!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);
-		schedule();
-		spin_lock(&vcpu->arch.local_int.float_int->lock);
-		spin_lock_bh(&vcpu->arch.local_int.lock);
-	}
+	kvm_vcpu_block(vcpu);
 	__unset_cpu_idle(vcpu);
-	__set_current_state(TASK_RUNNING);
-	remove_wait_queue(&vcpu->wq, &wait);
-	spin_unlock_bh(&vcpu->arch.local_int.lock);
-	spin_unlock(&vcpu->arch.local_int.float_int->lock);
 	vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
 
 	hrtimer_try_to_cancel(&vcpu->arch.ckc_timer);
 	return 0;
 }
 
-void kvm_s390_tasklet(unsigned long parm)
+void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu)
 {
-	struct kvm_vcpu *vcpu = (struct kvm_vcpu *) parm;
-
-	spin_lock(&vcpu->arch.local_int.lock);
-	vcpu->arch.local_int.timer_due = 1;
-	if (waitqueue_active(&vcpu->wq))
+	if (waitqueue_active(&vcpu->wq)) {
+		/*
+		 * The vcpu gave up the cpu voluntarily, mark it as a good
+		 * yield-candidate.
+		 */
+		vcpu->preempted = true;
 		wake_up_interruptible(&vcpu->wq);
-	spin_unlock(&vcpu->arch.local_int.lock);
+	}
 }
 
-/*
- * low level hrtimer wake routine. Because this runs in hardirq context
- * we schedule a tasklet to do the real work.
- */
 enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer)
 {
 	struct kvm_vcpu *vcpu;
 
 	vcpu = container_of(timer, struct kvm_vcpu, arch.ckc_timer);
-	vcpu->preempted = true;
-	tasklet_schedule(&vcpu->arch.tasklet);
+	kvm_s390_vcpu_wakeup(vcpu);
 
 	return HRTIMER_NORESTART;
 }
@@ -676,13 +647,13 @@ void kvm_s390_clear_local_irqs(struct kvm_vcpu *vcpu)
 	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 	struct kvm_s390_interrupt_info  *n, *inti = NULL;
 
-	spin_lock_bh(&li->lock);
+	spin_lock(&li->lock);
 	list_for_each_entry_safe(inti, n, &li->list, list) {
 		list_del(&inti->list);
 		kfree(inti);
 	}
 	atomic_set(&li->active, 0);
-	spin_unlock_bh(&li->lock);
+	spin_unlock(&li->lock);
 
 	/* clear pending external calls set by sigp interpretation facility */
 	atomic_clear_mask(CPUSTAT_ECALL_PEND, &vcpu->arch.sie_block->cpuflags);
@@ -701,7 +672,7 @@ void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
 	if (atomic_read(&li->active)) {
 		do {
 			deliver = 0;
-			spin_lock_bh(&li->lock);
+			spin_lock(&li->lock);
 			list_for_each_entry_safe(inti, n, &li->list, list) {
 				if (__interrupt_is_deliverable(vcpu, inti)) {
 					list_del(&inti->list);
@@ -712,7 +683,7 @@ void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
 			}
 			if (list_empty(&li->list))
 				atomic_set(&li->active, 0);
-			spin_unlock_bh(&li->lock);
+			spin_unlock(&li->lock);
 			if (deliver) {
 				__do_deliver_interrupt(vcpu, inti);
 				kfree(inti);
@@ -758,7 +729,7 @@ void kvm_s390_deliver_pending_machine_checks(struct kvm_vcpu *vcpu)
 	if (atomic_read(&li->active)) {
 		do {
 			deliver = 0;
-			spin_lock_bh(&li->lock);
+			spin_lock(&li->lock);
 			list_for_each_entry_safe(inti, n, &li->list, list) {
 				if ((inti->type == KVM_S390_MCHK) &&
 				    __interrupt_is_deliverable(vcpu, inti)) {
@@ -770,7 +741,7 @@ void kvm_s390_deliver_pending_machine_checks(struct kvm_vcpu *vcpu)
 			}
 			if (list_empty(&li->list))
 				atomic_set(&li->active, 0);
-			spin_unlock_bh(&li->lock);
+			spin_unlock(&li->lock);
 			if (deliver) {
 				__do_deliver_interrupt(vcpu, inti);
 				kfree(inti);
@@ -817,11 +788,11 @@ int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code)
 
 	VCPU_EVENT(vcpu, 3, "inject: program check %d (from kernel)", code);
 	trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, inti->type, code, 0, 1);
-	spin_lock_bh(&li->lock);
+	spin_lock(&li->lock);
 	list_add(&inti->list, &li->list);
 	atomic_set(&li->active, 1);
 	BUG_ON(waitqueue_active(li->wq));
-	spin_unlock_bh(&li->lock);
+	spin_unlock(&li->lock);
 	return 0;
 }
 
@@ -842,11 +813,11 @@ int kvm_s390_inject_prog_irq(struct kvm_vcpu *vcpu,
 
 	inti->type = KVM_S390_PROGRAM_INT;
 	memcpy(&inti->pgm, pgm_info, sizeof(inti->pgm));
-	spin_lock_bh(&li->lock);
+	spin_lock(&li->lock);
 	list_add(&inti->list, &li->list);
 	atomic_set(&li->active, 1);
 	BUG_ON(waitqueue_active(li->wq));
-	spin_unlock_bh(&li->lock);
+	spin_unlock(&li->lock);
 	return 0;
 }
 
@@ -934,12 +905,10 @@ static int __inject_vm(struct kvm *kvm, struct kvm_s390_interrupt_info *inti)
 	}
 	dst_vcpu = kvm_get_vcpu(kvm, sigcpu);
 	li = &dst_vcpu->arch.local_int;
-	spin_lock_bh(&li->lock);
+	spin_lock(&li->lock);
 	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
-	if (waitqueue_active(li->wq))
-		wake_up_interruptible(li->wq);
-	kvm_get_vcpu(kvm, sigcpu)->preempted = true;
-	spin_unlock_bh(&li->lock);
+	spin_unlock(&li->lock);
+	kvm_s390_vcpu_wakeup(kvm_get_vcpu(kvm, sigcpu));
 unlock_fi:
 	spin_unlock(&fi->lock);
 	mutex_unlock(&kvm->lock);
@@ -1081,7 +1050,7 @@ int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
 
 	mutex_lock(&vcpu->kvm->lock);
 	li = &vcpu->arch.local_int;
-	spin_lock_bh(&li->lock);
+	spin_lock(&li->lock);
 	if (inti->type == KVM_S390_PROGRAM_INT)
 		list_add(&inti->list, &li->list);
 	else
@@ -1090,11 +1059,9 @@ int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
 	if (inti->type == KVM_S390_SIGP_STOP)
 		li->action_bits |= ACTION_STOP_ON_STOP;
 	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
-	if (waitqueue_active(&vcpu->wq))
-		wake_up_interruptible(&vcpu->wq);
-	vcpu->preempted = true;
-	spin_unlock_bh(&li->lock);
+	spin_unlock(&li->lock);
 	mutex_unlock(&vcpu->kvm->lock);
+	kvm_s390_vcpu_wakeup(vcpu);
 	return 0;
 }
 
@@ -1589,8 +1556,7 @@ static int set_adapter_int(struct kvm_kernel_irq_routing_entry *e,
 	return ret;
 }
 
-int kvm_set_routing_entry(struct kvm_irq_routing_table *rt,
-			  struct kvm_kernel_irq_routing_entry *e,
+int kvm_set_routing_entry(struct kvm_kernel_irq_routing_entry *e,
 			  const struct kvm_irq_routing_entry *ue)
 {
 	int ret;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 2f3e14fe91a4..ce81eb2ab76a 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -146,7 +146,7 @@ long kvm_arch_dev_ioctl(struct file *filp,
 	return -EINVAL;
 }
 
-int kvm_dev_ioctl_check_extension(long ext)
+int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 {
 	int r;
 
@@ -166,7 +166,9 @@ int kvm_dev_ioctl_check_extension(long ext)
 	case KVM_CAP_IOEVENTFD:
 	case KVM_CAP_DEVICE_CTRL:
 	case KVM_CAP_ENABLE_CAP_VM:
+	case KVM_CAP_S390_IRQCHIP:
 	case KVM_CAP_VM_ATTRIBUTES:
+	case KVM_CAP_MP_STATE:
 		r = 1;
 		break;
 	case KVM_CAP_NR_VCPUS:
@@ -595,7 +597,8 @@ static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu)
 	vcpu->arch.sie_block->pp = 0;
 	vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
 	kvm_clear_async_pf_completion_queue(vcpu);
-	kvm_s390_vcpu_stop(vcpu);
+	if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm))
+		kvm_s390_vcpu_stop(vcpu);
 	kvm_s390_clear_local_irqs(vcpu);
 }
 
@@ -647,8 +650,6 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
 			return rc;
 	}
 	hrtimer_init(&vcpu->arch.ckc_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
-	tasklet_init(&vcpu->arch.tasklet, kvm_s390_tasklet,
-		     (unsigned long) vcpu);
 	vcpu->arch.ckc_timer.function = kvm_s390_idle_wakeup;
 	get_cpu_id(&vcpu->arch.cpu_id);
 	vcpu->arch.cpu_id.version = 0xff;
@@ -926,7 +927,7 @@ static int kvm_arch_vcpu_ioctl_set_initial_psw(struct kvm_vcpu *vcpu, psw_t psw)
 {
 	int rc = 0;
 
-	if (!(atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOPPED))
+	if (!is_vcpu_stopped(vcpu))
 		rc = -EBUSY;
 	else {
 		vcpu->run->psw_mask = psw.mask;
@@ -980,13 +981,34 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
 				    struct kvm_mp_state *mp_state)
 {
-	return -EINVAL; /* not implemented yet */
+	/* CHECK_STOP and LOAD are not supported yet */
+	return is_vcpu_stopped(vcpu) ? KVM_MP_STATE_STOPPED :
+				       KVM_MP_STATE_OPERATING;
 }
 
 int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
 				    struct kvm_mp_state *mp_state)
 {
-	return -EINVAL; /* not implemented yet */
+	int rc = 0;
+
+	/* user space knows about this interface - let it control the state */
+	vcpu->kvm->arch.user_cpu_state_ctrl = 1;
+
+	switch (mp_state->mp_state) {
+	case KVM_MP_STATE_STOPPED:
+		kvm_s390_vcpu_stop(vcpu);
+		break;
+	case KVM_MP_STATE_OPERATING:
+		kvm_s390_vcpu_start(vcpu);
+		break;
+	case KVM_MP_STATE_LOAD:
+	case KVM_MP_STATE_CHECK_STOP:
+		/* fall through - CHECK_STOP and LOAD are not supported yet */
+	default:
+		rc = -ENXIO;
+	}
+
+	return rc;
 }
 
 bool kvm_s390_cmma_enabled(struct kvm *kvm)
@@ -1045,6 +1067,9 @@ retry:
 		goto retry;
 	}
 
+	/* nothing to do, just clear the request */
+	clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
+
 	return 0;
 }
 
@@ -1284,7 +1309,13 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 	if (vcpu->sigset_active)
 		sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
 
-	kvm_s390_vcpu_start(vcpu);
+	if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) {
+		kvm_s390_vcpu_start(vcpu);
+	} else if (is_vcpu_stopped(vcpu)) {
+		pr_err_ratelimited("kvm-s390: can't run stopped vcpu %d\n",
+				   vcpu->vcpu_id);
+		return -EINVAL;
+	}
 
 	switch (kvm_run->exit_reason) {
 	case KVM_EXIT_S390_SIEIC:
@@ -1413,11 +1444,6 @@ int kvm_s390_vcpu_store_status(struct kvm_vcpu *vcpu, unsigned long addr)
 	return kvm_s390_store_status_unloaded(vcpu, addr);
 }
 
-static inline int is_vcpu_stopped(struct kvm_vcpu *vcpu)
-{
-	return atomic_read(&(vcpu)->arch.sie_block->cpuflags) & CPUSTAT_STOPPED;
-}
-
 static void __disable_ibs_on_vcpu(struct kvm_vcpu *vcpu)
 {
 	kvm_check_request(KVM_REQ_ENABLE_IBS, vcpu);
@@ -1451,7 +1477,7 @@ void kvm_s390_vcpu_start(struct kvm_vcpu *vcpu)
 
 	trace_kvm_s390_vcpu_start_stop(vcpu->vcpu_id, 1);
 	/* Only one cpu at a time may enter/leave the STOPPED state. */
-	spin_lock_bh(&vcpu->kvm->arch.start_stop_lock);
+	spin_lock(&vcpu->kvm->arch.start_stop_lock);
 	online_vcpus = atomic_read(&vcpu->kvm->online_vcpus);
 
 	for (i = 0; i < online_vcpus; i++) {
@@ -1477,7 +1503,7 @@ void kvm_s390_vcpu_start(struct kvm_vcpu *vcpu)
 	 * Let's play safe and flush the VCPU at startup.
 	 */
 	vcpu->arch.sie_block->ihcpu  = 0xffff;
-	spin_unlock_bh(&vcpu->kvm->arch.start_stop_lock);
+	spin_unlock(&vcpu->kvm->arch.start_stop_lock);
 	return;
 }
 
@@ -1491,10 +1517,18 @@ void kvm_s390_vcpu_stop(struct kvm_vcpu *vcpu)
 
 	trace_kvm_s390_vcpu_start_stop(vcpu->vcpu_id, 0);
 	/* Only one cpu at a time may enter/leave the STOPPED state. */
-	spin_lock_bh(&vcpu->kvm->arch.start_stop_lock);
+	spin_lock(&vcpu->kvm->arch.start_stop_lock);
 	online_vcpus = atomic_read(&vcpu->kvm->online_vcpus);
 
+	/* Need to lock access to action_bits to avoid a SIGP race condition */
+	spin_lock(&vcpu->arch.local_int.lock);
 	atomic_set_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
+
+	/* SIGP STOP and SIGP STOP AND STORE STATUS has been fully processed */
+	vcpu->arch.local_int.action_bits &=
+				 ~(ACTION_STOP_ON_STOP | ACTION_STORE_ON_STOP);
+	spin_unlock(&vcpu->arch.local_int.lock);
+
 	__disable_ibs_on_vcpu(vcpu);
 
 	for (i = 0; i < online_vcpus; i++) {
@@ -1512,7 +1546,7 @@ void kvm_s390_vcpu_stop(struct kvm_vcpu *vcpu)
 		__enable_ibs_on_vcpu(started_vcpu);
 	}
 
-	spin_unlock_bh(&vcpu->kvm->arch.start_stop_lock);
+	spin_unlock(&vcpu->kvm->arch.start_stop_lock);
 	return;
 }
 
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index a8655ed31616..3862fa2cefe0 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -45,9 +45,9 @@ do { \
 	  d_args); \
 } while (0)
 
-static inline int __cpu_is_stopped(struct kvm_vcpu *vcpu)
+static inline int is_vcpu_stopped(struct kvm_vcpu *vcpu)
 {
-	return atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOP_INT;
+	return atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOPPED;
 }
 
 static inline int kvm_is_ucontrol(struct kvm *kvm)
@@ -129,9 +129,15 @@ static inline void kvm_s390_set_psw_cc(struct kvm_vcpu *vcpu, unsigned long cc)
 	vcpu->arch.sie_block->gpsw.mask |= cc << 44;
 }
 
+/* are cpu states controlled by user space */
+static inline int kvm_s390_user_cpu_state_ctrl(struct kvm *kvm)
+{
+	return kvm->arch.user_cpu_state_ctrl != 0;
+}
+
 int kvm_s390_handle_wait(struct kvm_vcpu *vcpu);
+void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu);
 enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer);
-void kvm_s390_tasklet(unsigned long parm);
 void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu);
 void kvm_s390_deliver_pending_machine_checks(struct kvm_vcpu *vcpu);
 void kvm_s390_clear_local_irqs(struct kvm_vcpu *vcpu);
diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c
index 43079a48cc98..cf243ba3d50f 100644
--- a/arch/s390/kvm/sigp.c
+++ b/arch/s390/kvm/sigp.c
@@ -125,8 +125,9 @@ static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
 	return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED;
 }
 
-static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
+static int __inject_sigp_stop(struct kvm_vcpu *dst_vcpu, int action)
 {
+	struct kvm_s390_local_interrupt *li = &dst_vcpu->arch.local_int;
 	struct kvm_s390_interrupt_info *inti;
 	int rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 
@@ -135,7 +136,13 @@ static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
 		return -ENOMEM;
 	inti->type = KVM_S390_SIGP_STOP;
 
-	spin_lock_bh(&li->lock);
+	spin_lock(&li->lock);
+	if (li->action_bits & ACTION_STOP_ON_STOP) {
+		/* another SIGP STOP is pending */
+		kfree(inti);
+		rc = SIGP_CC_BUSY;
+		goto out;
+	}
 	if ((atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 		kfree(inti);
 		if ((action & ACTION_STORE_ON_STOP) != 0)
@@ -144,19 +151,17 @@ static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
 	}
 	list_add_tail(&inti->list, &li->list);
 	atomic_set(&li->active, 1);
-	atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
 	li->action_bits |= action;
-	if (waitqueue_active(li->wq))
-		wake_up_interruptible(li->wq);
+	atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
+	kvm_s390_vcpu_wakeup(dst_vcpu);
 out:
-	spin_unlock_bh(&li->lock);
+	spin_unlock(&li->lock);
 
 	return rc;
 }
 
 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
 {
-	struct kvm_s390_local_interrupt *li;
 	struct kvm_vcpu *dst_vcpu = NULL;
 	int rc;
 
@@ -166,9 +171,8 @@ static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
 	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;
-	li = &dst_vcpu->arch.local_int;
 
-	rc = __inject_sigp_stop(li, action);
+	rc = __inject_sigp_stop(dst_vcpu, action);
 
 	VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
 
@@ -238,7 +242,7 @@ static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 	if (!inti)
 		return SIGP_CC_BUSY;
 
-	spin_lock_bh(&li->lock);
+	spin_lock(&li->lock);
 	/* cpu must be in stopped state */
 	if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 		*reg &= 0xffffffff00000000UL;
@@ -253,13 +257,12 @@ static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 
 	list_add_tail(&inti->list, &li->list);
 	atomic_set(&li->active, 1);
-	if (waitqueue_active(li->wq))
-		wake_up_interruptible(li->wq);
+	kvm_s390_vcpu_wakeup(dst_vcpu);
 	rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 
 	VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
 out_li:
-	spin_unlock_bh(&li->lock);
+	spin_unlock(&li->lock);
 	return rc;
 }
 
@@ -275,9 +278,9 @@ static int __sigp_store_status_at_addr(struct kvm_vcpu *vcpu, u16 cpu_id,
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;
 
-	spin_lock_bh(&dst_vcpu->arch.local_int.lock);
+	spin_lock(&dst_vcpu->arch.local_int.lock);
 	flags = atomic_read(dst_vcpu->arch.local_int.cpuflags);
-	spin_unlock_bh(&dst_vcpu->arch.local_int.lock);
+	spin_unlock(&dst_vcpu->arch.local_int.lock);
 	if (!(flags & CPUSTAT_STOPPED)) {
 		*reg &= 0xffffffff00000000UL;
 		*reg |= SIGP_STATUS_INCORRECT_STATE;
@@ -338,10 +341,10 @@ static int sigp_check_callable(struct kvm_vcpu *vcpu, u16 cpu_addr)
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;
 	li = &dst_vcpu->arch.local_int;
-	spin_lock_bh(&li->lock);
+	spin_lock(&li->lock);
 	if (li->action_bits & ACTION_STOP_ON_STOP)
 		rc = SIGP_CC_BUSY;
-	spin_unlock_bh(&li->lock);
+	spin_unlock(&li->lock);
 
 	return rc;
 }
@@ -461,12 +464,7 @@ int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu)
 		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_vcpu_wakeup(dest_vcpu);
 		kvm_s390_set_psw_cc(vcpu, SIGP_CC_ORDER_CODE_ACCEPTED);
 		return 0;
 	}