commit c0d64cb031c21f163a0ec15cf10844bcf0ceedcf
author Len Brown <len.brown@intel.com> Sat May 22 16:34:10 2010 -0400
committer Len Brown <len.brown@intel.com> Thu May 27 13:04:04 2010 -0400
tree ce65dc6b8cbda91e8c1f1c69753265618e8d9ae6
parent 6b2c676bf32be91f43215d5874c07c1becaba013

cpuidle: add cpuidle_unregister_driver() error check

Assure that cpuidle_unregister_driver() will not clobber
the registered driver if unregistered by somebody else.

Signed-off-by: Len Brown <len.brown@intel.com>

drivers/cpuidle/driver.c

diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index 2257004..826b5c0 100644
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -45,8 +45,11 @@
  */
 void cpuidle_unregister_driver(struct cpuidle_driver *drv)
 {
-	if (!drv)
+	if (drv != cpuidle_curr_driver) {
+		WARN(1, "invalid cpuidle_unregister_driver(%s)\n",
+			drv->name);
 		return;
+	}
 
 	spin_lock(&cpuidle_driver_lock);
 	cpuidle_curr_driver = NULL;