diff options
| -rw-r--r-- | drivers/tty/serial/serial_core.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 487756947a96..89cebdd27841 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -643,7 +643,10 @@ static unsigned int uart_write_room(struct tty_struct *tty) unsigned int ret; port = uart_port_ref_lock(state, &flags); - ret = kfifo_avail(&state->port.xmit_fifo); + if (!state->port.xmit_buf) + ret = 0; + else + ret = kfifo_avail(&state->port.xmit_fifo); uart_port_unlock_deref(port, flags); return ret; } |