PM / devfreq: Add proper locking around list_del()

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>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 478006b7764a..66d3c7184a0f 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -594,17 +594,19 @@ struct devfreq *devfreq_add_device(struct device *dev,
         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_out:
         return ERR_PTR(err);