serial: 8250: lock port for stop_rx() in omap8250_irq()

[ Upstream commit ca73a892c5bec4b08a2fa22b3015e98ed905abb7 ]

The uarts_ops stop_rx() callback expects that the port->lock is
taken and interrupts are disabled.

Fixes: 1fe0e1fa3209 ("serial: 8250_omap: Handle optional overrun-throttle-ms property")
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20230525093159.223817-4-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 79bdf93..7ecd2d3 100644 (file)
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -641,7 +641,9 @@ static irqreturn_t omap8250_irq(int irq, void *dev_id)
 
                up->ier = port->serial_in(port, UART_IER);
                if (up->ier & (UART_IER_RLSI | UART_IER_RDI)) {
+                       spin_lock(&port->lock);
                        port->ops->stop_rx(port);
+                       spin_unlock(&port->lock);
                } else {
                        /* Keep restarting the timer until
                         * the input overrun subsides.