n_tty: Ensure reader restarts worker for next reader
A departing reader must restart a flush_to_ldisc() worker _before_
the next reader enters the read loop; this is to avoid the new reader
concluding no more i/o is available and prematurely exiting, when the
old reader simply hasn't re-started the worker yet.
Cc: stable <stable@vger.kernel.org> # 3.12
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 7cdd1eb..a2b70c9 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -2243,6 +2243,9 @@
if (time)
timeout = time;
}
+ n_tty_set_room(tty);
+ up_read(&tty->termios_rwsem);
+
mutex_unlock(&ldata->atomic_read_lock);
remove_wait_queue(&tty->read_wait, &wait);
@@ -2253,8 +2256,6 @@
if (b - buf)
retval = b - buf;
- n_tty_set_room(tty);
- up_read(&tty->termios_rwsem);
return retval;
}