[PATCH 3.16 145/370] PM / devfreq: Add proper locking around list_del()

Ben Hutchings
2017-03-10T13:46:46Z

From: Axel Lin <axel.lin@ingics.com>

commit 0f376c9cd86c23f37312d37748b233660ef9d9af upstream.

Use devfreq_list_lock around list_del() to prevent list corruption.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/devfreq/devfreq.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -507,17 +507,19 @@ struct devfreq *devfreq_add_device(struc
if (devfreq->governor)
err = devfreq->governor->event_handler(devfreq,
DEVFREQ_GOV_START, NULL);
- mutex_unlock(&devfreq_list_lock);
if (err) {
dev_err(dev, "%s: Unable to start governor for the device\n",
__func__);
goto err_init;
}
+ mutex_unlock(&devfreq_list_lock);

return devfreq;

err_init:
list_del(&devfreq->node);
+ mutex_unlock(&devfreq_list_lock);
+
device_unregister(&devfreq->dev);
err_dev:
kfree(devfreq);