In serial8250_rx_chars(), max_count is set to 256. Due to the post-decrement operator used in the while() condition, the maximum number of iterations actually 257. This is not a problem, but it is mildly surprising if you're debugging. Use pre-decrement instead. Signed-off-by: Frans Klaver <frans.klaver@xxxxxxxxx> --- drivers/tty/serial/8250/8250_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index a06084d..cc9f1a8 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -1485,7 +1485,7 @@ serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr) ignore_char: lsr = serial_in(up, UART_LSR); - } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0)); + } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (--max_count > 0)); spin_unlock(&port->lock); tty_flip_buffer_push(&port->state->port); spin_lock(&port->lock); -- 2.1.0 -- 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