1 files changed, 12 insertions, 9 deletions

diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index 17e8eb93a76c..69ffd1dc1de7 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -387,6 +387,7 @@ EXPORT_SYMBOL(acpi_bus_power_manageable);
 
 #ifdef CONFIG_PM
 static DEFINE_MUTEX(acpi_pm_notifier_lock);
+static DEFINE_MUTEX(acpi_pm_notifier_install_lock);
 
 void acpi_pm_wakeup_event(struct device *dev)
 {
@@ -443,24 +444,25 @@ acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
         if (!dev && !func)
                 return AE_BAD_PARAMETER;
 
-        mutex_lock(&acpi_pm_notifier_lock);
+        mutex_lock(&acpi_pm_notifier_install_lock);
 
         if (adev->wakeup.flags.notifier_present)
                 goto out;
 
-        adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev));
-        adev->wakeup.context.dev = dev;
-        adev->wakeup.context.func = func;
-
         status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
                                              acpi_pm_notify_handler, NULL);
         if (ACPI_FAILURE(status))
                 goto out;
 
+        mutex_lock(&acpi_pm_notifier_lock);
+        adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev));
+        adev->wakeup.context.dev = dev;
+        adev->wakeup.context.func = func;
         adev->wakeup.flags.notifier_present = true;
+        mutex_unlock(&acpi_pm_notifier_lock);
 
  out:
-        mutex_unlock(&acpi_pm_notifier_lock);
+        mutex_unlock(&acpi_pm_notifier_install_lock);
         return status;
 }
 
@@ -472,7 +474,7 @@ acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
 {
         acpi_status status = AE_BAD_PARAMETER;
 
-        mutex_lock(&acpi_pm_notifier_lock);
+        mutex_lock(&acpi_pm_notifier_install_lock);
 
         if (!adev->wakeup.flags.notifier_present)
                 goto out;
@@ -483,14 +485,15 @@ acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
         if (ACPI_FAILURE(status))
                 goto out;
 
+        mutex_lock(&acpi_pm_notifier_lock);
         adev->wakeup.context.func = NULL;
         adev->wakeup.context.dev = NULL;
         wakeup_source_unregister(adev->wakeup.ws);
-
         adev->wakeup.flags.notifier_present = false;
+        mutex_unlock(&acpi_pm_notifier_lock);
 
  out:
-        mutex_unlock(&acpi_pm_notifier_lock);
+        mutex_unlock(&acpi_pm_notifier_install_lock);
         return status;
 }