2 files changed, 15 insertions, 4 deletions

diff --git a/drivers/rtc/rtc-dev.c b/drivers/rtc/rtc-dev.c
index 90dfa0df747a..0114a78b7cbb 100644
--- a/drivers/rtc/rtc-dev.c
+++ b/drivers/rtc/rtc-dev.c
@@ -13,6 +13,7 @@
 
 #include <linux/module.h>
 #include <linux/rtc.h>
+#include <linux/smp_lock.h>
 #include "rtc-core.h"
 
 static dev_t rtc_devt;
@@ -26,8 +27,11 @@ static int rtc_dev_open(struct inode *inode, struct file *file)
                                         struct rtc_device, char_dev);
         const struct rtc_class_ops *ops = rtc->ops;
 
-        if (test_and_set_bit_lock(RTC_DEV_BUSY, &rtc->flags))
-                return -EBUSY;
+        lock_kernel();
+        if (test_and_set_bit_lock(RTC_DEV_BUSY, &rtc->flags)) {
+                err = -EBUSY;
+                goto out;
+        }
 
         file->private_data = rtc;
 
@@ -37,11 +41,13 @@ static int rtc_dev_open(struct inode *inode, struct file *file)
                 rtc->irq_data = 0;
                 spin_unlock_irq(&rtc->irq_lock);
 
-                return 0;
+                goto out;
         }
 
         /* something has gone wrong */
         clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags);
+out:
+        unlock_kernel();
         return err;
 }
 
diff --git a/drivers/rtc/rtc-m41t80.c b/drivers/rtc/rtc-m41t80.c
index a3e0880b38fb..0a19c06019be 100644
--- a/drivers/rtc/rtc-m41t80.c
+++ b/drivers/rtc/rtc-m41t80.c
@@ -17,6 +17,7 @@
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/slab.h>
+#include <linux/smp_lock.h>
 #include <linux/string.h>
 #include <linux/i2c.h>
 #include <linux/rtc.h>
@@ -655,12 +656,16 @@ static int wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 static int wdt_open(struct inode *inode, struct file *file)
 {
         if (MINOR(inode->i_rdev) == WATCHDOG_MINOR) {
-                if (test_and_set_bit(0, &wdt_is_open))
+                lock_kernel();
+                if (test_and_set_bit(0, &wdt_is_open)) {
+                        unlock_kernel();
                         return -EBUSY;
+                }
                 /*
                  *      Activate
                  */
                 wdt_is_open = 1;
+                unlock_kernel();
                 return 0;
         }
         return -ENODEV;