[PATCH 05/16] intel_idle: Fix dangling registration on error path.

[Tim Gardner]

From: Richard Cochran <rcochran at linutronix.de>

BugLink: http://bugs.launchpad.net/bugs/1591821

In the module_init() method, if the per-CPU allocation fails, then the
active cpuidle registration is not cleaned up.  This patch fixes the
issue by attempting the allocation before registration, and then
cleaning it up again on registration failure.

Signed-off-by: Richard Cochran <rcochran at linutronix.de>
Signed-off-by: Len Brown <len.brown at intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki at intel.com>
(cherry picked from commit e9df69ccd1322e87eee10f28036fad9e6c71f8dd)
Signed-off-by: Tim Gardner <tim.gardner at canonical.com>
---
 drivers/idle/intel_idle.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 4a1de3d..5dd741f 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -1210,19 +1210,20 @@ static int __init intel_idle_init(void)
 	if (retval)
 		return retval;
 
+	intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
+	if (intel_idle_cpuidle_devices == NULL)
+		return -ENOMEM;
+
 	intel_idle_cpuidle_driver_init();
 	retval = cpuidle_register_driver(&intel_idle_driver);
 	if (retval) {
 		struct cpuidle_driver *drv = cpuidle_get_driver();
 		printk(KERN_DEBUG PREFIX "intel_idle yielding to %s",
 			drv ? drv->name : "none");
+		free_percpu(intel_idle_cpuidle_devices);
 		return retval;
 	}
 
-	intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
-	if (intel_idle_cpuidle_devices == NULL)
-		return -ENOMEM;
-
 	cpu_notifier_register_begin();
 
 	for_each_online_cpu(i) {
-- 
2.7.4