1 files changed, 6 insertions, 1 deletions

diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c
index 0afe32be4c85..8cb757026386 100644
--- a/kernel/pm_qos_params.c
+++ b/kernel/pm_qos_params.c
@@ -29,6 +29,7 @@
 
 #include <linux/pm_qos_params.h>
 #include <linux/sched.h>
+#include <linux/smp_lock.h>
 #include <linux/spinlock.h>
 #include <linux/slab.h>
 #include <linux/time.h>
@@ -358,15 +359,19 @@ static int pm_qos_power_open(struct inode *inode, struct file *filp)
         int ret;
         long pm_qos_class;
 
+        lock_kernel();
         pm_qos_class = find_pm_qos_object_by_minor(iminor(inode));
         if (pm_qos_class >= 0) {
                 filp->private_data = (void *)pm_qos_class;
                 sprintf(name, "process_%d", current->pid);
                 ret = pm_qos_add_requirement(pm_qos_class, name,
                                         PM_QOS_DEFAULT_VALUE);
-                if (ret >= 0)
+                if (ret >= 0) {
+                        unlock_kernel();
                         return 0;
+                }
         }
+        unlock_kernel();
 
         return -EPERM;
 }