ACPI: thermal: Check whether cooling device exists before unregistering

OS should check whether the cooling device exists before it is unregistered.
If it doesn't exists, it is unnecessary to remove the sysfs link
and call the function of thermal_cooling_device_unregister.

http://bugzilla.kernel.org/show_bug.cgi?id=9982

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Tested-by    : Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 75ccf5d18bf4e3630e892dd0021a8c890a0fc0c2..697335c8423e3865e93ae906834c97386d358d24 100644 (file)
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -809,10 +809,12 @@ static int acpi_processor_remove(struct acpi_device *device, int type)
 
        acpi_processor_remove_fs(device);
 
-       sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
-       sysfs_remove_link(&pr->cdev->device.kobj, "device");
-       thermal_cooling_device_unregister(pr->cdev);
-       pr->cdev = NULL;
+       if (pr->cdev) {
+               sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
+               sysfs_remove_link(&pr->cdev->device.kobj, "device");
+               thermal_cooling_device_unregister(pr->cdev);
+               pr->cdev = NULL;
+       }
 
        processors[pr->id] = NULL;