1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 5d405a1bfbe3..7710a6a77d97 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -3770,7 +3770,9 @@ int tty_register_driver(struct tty_driver *driver)
         if (!driver->put_char)
                 driver->put_char = tty_default_put_char;
         
+        mutex_lock(&tty_mutex);
         list_add(&driver->tty_drivers, &tty_drivers);
+        mutex_unlock(&tty_mutex);
         
         if ( !(driver->flags & TTY_DRIVER_DYNAMIC_DEV) ) {
                 for(i = 0; i < driver->num; i++)
@@ -3796,8 +3798,9 @@ int tty_unregister_driver(struct tty_driver *driver)
 
         unregister_chrdev_region(MKDEV(driver->major, driver->minor_start),
                                 driver->num);
-
+        mutex_lock(&tty_mutex);
         list_del(&driver->tty_drivers);
+        mutex_unlock(&tty_mutex);
 
         /*
          * Free the termios and termios_locked structures because