tty: Convert termios_mutex to termios_rwsem
termios is commonly accessed unsafely (especially by N_TTY)
because the existing mutex forces exclusive access.
Convert existing usage.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index d159059..ab923bb2 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -1539,7 +1539,7 @@
* guaranteed that this function will not be re-entered or in progress
* when the ldisc is closed.
*
- * Locking: Caller holds tty->termios_mutex
+ * Locking: Caller holds tty->termios_rwsem
*/
static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)