The first amba port does not always have an attached tty, which will result in a crash if the work-around is activated. This seems to be the case for example on Snowball which has no modem hw, which seems to be the main use-case for this work-around. --- drivers/tty/serial/amba-pl011.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 6800f5f..c3ffbed 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1061,6 +1061,10 @@ static void pl011_lockup_wa(unsigned long data) int buf_empty_retries = 200; int loop; + /* Exit early if there is no tty */ + if (!tty) + return; + /* Stop HCI layer from submitting data for tx */ tty->hw_stopped = 1; while (!uart_circ_empty(xmit)) { -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html