4 files changed, 44 insertions, 11 deletions

diff --git a/drivers/cpuidle/coupled.c b/drivers/cpuidle/coupled.c
index 7936dce4b878..344058f8501a 100644
--- a/drivers/cpuidle/coupled.c
+++ b/drivers/cpuidle/coupled.c
@@ -176,19 +176,39 @@ void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev, atomic_t *a)
 
 /**
  * cpuidle_state_is_coupled - check if a state is part of a coupled set
- * @dev: struct cpuidle_device for the current cpu
  * @drv: struct cpuidle_driver for the platform
  * @state: index of the target state in drv->states
  *
  * Returns true if the target state is coupled with cpus besides this one
  */
-bool cpuidle_state_is_coupled(struct cpuidle_device *dev,
-	struct cpuidle_driver *drv, int state)
+bool cpuidle_state_is_coupled(struct cpuidle_driver *drv, int state)
 {
 	return drv->states[state].flags & CPUIDLE_FLAG_COUPLED;
 }
 
 /**
+ * cpuidle_coupled_state_verify - check if the coupled states are correctly set.
+ * @drv: struct cpuidle_driver for the platform
+ *
+ * Returns 0 for valid state values, a negative error code otherwise:
+ *  * -EINVAL if any coupled state(safe_state_index) is wrongly set.
+ */
+int cpuidle_coupled_state_verify(struct cpuidle_driver *drv)
+{
+	int i;
+
+	for (i = drv->state_count - 1; i >= 0; i--) {
+		if (cpuidle_state_is_coupled(drv, i) &&
+		    (drv->safe_state_index == i ||
+		     drv->safe_state_index < 0 ||
+		     drv->safe_state_index >= drv->state_count))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
  * cpuidle_coupled_set_ready - mark a cpu as ready
  * @coupled: the struct coupled that contains the current cpu
  */
@@ -473,7 +493,7 @@ int cpuidle_enter_state_coupled(struct cpuidle_device *dev,
 			return entered_state;
 		}
 		entered_state = cpuidle_enter_state(dev, drv,
-			dev->safe_state_index);
+			drv->safe_state_index);
 		local_irq_disable();
 	}
 
@@ -521,7 +541,7 @@ retry:
 		}
 
 		entered_state = cpuidle_enter_state(dev, drv,
-			dev->safe_state_index);
+			drv->safe_state_index);
 		local_irq_disable();
 	}
 
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 48b7228563ad..17a6dc0e2111 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -123,6 +123,7 @@ static void enter_freeze_proper(struct cpuidle_driver *drv,
 	 * cpuidle mechanism enables interrupts and doing that with timekeeping
 	 * suspended is generally unsafe.
 	 */
+	stop_critical_timings();
 	drv->states[index].enter_freeze(dev, drv, index);
 	WARN_ON(!irqs_disabled());
 	/*
@@ -131,6 +132,7 @@ static void enter_freeze_proper(struct cpuidle_driver *drv,
 	 * critical sections, so tell RCU about that.
 	 */
 	RCU_NONIDLE(tick_unfreeze());
+	start_critical_timings();
 }
 
 /**
@@ -195,7 +197,9 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv,
 	trace_cpu_idle_rcuidle(index, dev->cpu);
 	time_start = ktime_get();
 
+	stop_critical_timings();
 	entered_state = target_state->enter(dev, drv, index);
+	start_critical_timings();
 
 	time_end = ktime_get();
 	trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu);
@@ -210,7 +214,7 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv,
 		tick_broadcast_exit();
 	}
 
-	if (!cpuidle_state_is_coupled(dev, drv, entered_state))
+	if (!cpuidle_state_is_coupled(drv, entered_state))
 		local_irq_enable();
 
 	diff = ktime_to_us(ktime_sub(time_end, time_start));
@@ -259,7 +263,7 @@ int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
 int cpuidle_enter(struct cpuidle_driver *drv, struct cpuidle_device *dev,
 		  int index)
 {
-	if (cpuidle_state_is_coupled(dev, drv, index))
+	if (cpuidle_state_is_coupled(drv, index))
 		return cpuidle_enter_state_coupled(dev, drv, index);
 	return cpuidle_enter_state(dev, drv, index);
 }
diff --git a/drivers/cpuidle/cpuidle.h b/drivers/cpuidle/cpuidle.h
index ee97e9672ecf..f87f399b0540 100644
--- a/drivers/cpuidle/cpuidle.h
+++ b/drivers/cpuidle/cpuidle.h
@@ -34,19 +34,24 @@ extern int cpuidle_add_sysfs(struct cpuidle_device *dev);
 extern void cpuidle_remove_sysfs(struct cpuidle_device *dev);
 
 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
-bool cpuidle_state_is_coupled(struct cpuidle_device *dev,
-		struct cpuidle_driver *drv, int state);
+bool cpuidle_state_is_coupled(struct cpuidle_driver *drv, int state);
+int cpuidle_coupled_state_verify(struct cpuidle_driver *drv);
 int cpuidle_enter_state_coupled(struct cpuidle_device *dev,
 		struct cpuidle_driver *drv, int next_state);
 int cpuidle_coupled_register_device(struct cpuidle_device *dev);
 void cpuidle_coupled_unregister_device(struct cpuidle_device *dev);
 #else
-static inline bool cpuidle_state_is_coupled(struct cpuidle_device *dev,
-		struct cpuidle_driver *drv, int state)
+static inline
+bool cpuidle_state_is_coupled(struct cpuidle_driver *drv, int state)
 {
 	return false;
 }
 
+static inline int cpuidle_coupled_state_verify(struct cpuidle_driver *drv)
+{
+	return 0;
+}
+
 static inline int cpuidle_enter_state_coupled(struct cpuidle_device *dev,
 		struct cpuidle_driver *drv, int next_state)
 {
diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index 5db147859b90..389ade4572be 100644
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -227,6 +227,10 @@ static int __cpuidle_register_driver(struct cpuidle_driver *drv)
 	if (!drv || !drv->state_count)
 		return -EINVAL;
 
+	ret = cpuidle_coupled_state_verify(drv);
+	if (ret)
+		return ret;
+
 	if (cpuidle_disabled())
 		return -ENODEV;