1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/char/rtc.c b/drivers/char/rtc.c
index 909cac93fa2a..fa92a8af5a5a 100644
--- a/drivers/char/rtc.c
+++ b/drivers/char/rtc.c
@@ -73,6 +73,7 @@
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <linux/spinlock.h>
+#include <linux/smp_lock.h>
 #include <linux/sysctl.h>
 #include <linux/wait.h>
 #include <linux/bcd.h>
@@ -734,6 +735,7 @@ static int rtc_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
  * needed here. Or anywhere else in this driver. */
 static int rtc_open(struct inode *inode, struct file *file)
 {
+        lock_kernel();
         spin_lock_irq(&rtc_lock);
 
         if (rtc_status & RTC_IS_OPEN)
@@ -743,10 +745,12 @@ static int rtc_open(struct inode *inode, struct file *file)
 
         rtc_irq_data = 0;
         spin_unlock_irq(&rtc_lock);
+        unlock_kernel();
         return 0;
 
 out_busy:
         spin_unlock_irq(&rtc_lock);
+        unlock_kernel();
         return -EBUSY;
 }