1 files changed, 3 insertions, 0 deletions

diff --git a/fs/proc/proc_tty.c b/fs/proc/proc_tty.c
index c1bbfbeb035e..b3a473b0a191 100644
--- a/fs/proc/proc_tty.c
+++ b/fs/proc/proc_tty.c
@@ -108,6 +108,8 @@ static void *t_start(struct seq_file *m, loff_t *pos)
 {
         struct list_head *p;
         loff_t l = *pos;
+
+        mutex_lock(&tty_mutex);
         list_for_each(p, &tty_drivers)
                 if (!l--)
                         return list_entry(p, struct tty_driver, tty_drivers);
@@ -124,6 +126,7 @@ static void *t_next(struct seq_file *m, void *v, loff_t *pos)
 
 static void t_stop(struct seq_file *m, void *v)
 {
+        mutex_unlock(&tty_mutex);
 }
 
 static struct seq_operations tty_drivers_op = {