The sunsu driver has been carrying a workaround for the infamous low_latency behaviour of tty_flip_buffer_push() by dropping and reacquiring the port lock in the interrupt handler since 2004. Since commit a9c3f68f3cd8 ("tty: Fix low_latency BUG"), tty_flip_buffer_push() always schedules a work item to push data to the line discipline and there's no need to keep any low_latency hacks around. Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> --- drivers/tty/serial/sunsu.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/tty/serial/sunsu.c b/drivers/tty/serial/sunsu.c index 319e5ceb6130..12c2468f2b0e 100644 --- a/drivers/tty/serial/sunsu.c +++ b/drivers/tty/serial/sunsu.c @@ -466,12 +466,8 @@ static irqreturn_t sunsu_serial_interrupt(int irq, void *dev_id) if (status & UART_LSR_THRE) transmit_chars(up); - spin_unlock_irqrestore(&up->port.lock, flags); - tty_flip_buffer_push(&up->port.state->port); - spin_lock_irqsave(&up->port.lock, flags); - } while (!(serial_in(up, UART_IIR) & UART_IIR_NO_INT)); spin_unlock_irqrestore(&up->port.lock, flags); -- 2.26.3