From 72bad20e9316bf6203def57256a5ade158585558 Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Fri, 6 Jul 2018 11:08:36 +0200
Subject: [PATCH] serial: sh-sci: Stop RX FIFO timer during port shutdown

[ Upstream commit c5a9262fa8bfed0dddc7466ef10fcd292e2af61b ]

The RX FIFO timer may be armed when the port is shut down, hence the
timer function may still be called afterwards.

Fix this race condition by deleting the timer during port shutdown.

Fixes: 039403765e5da3c6 ("serial: sh-sci: SCIFA/B RX FIFO software timeout")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/tty/serial/sh-sci.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 8bc8fe2b75f7..37dba940d898 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -2060,6 +2060,8 @@ static void sci_shutdown(struct uart_port *port)
 	}
 #endif
 
+	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0)
+		del_timer_sync(&s->rx_fifo_timer);
 	sci_free_irq(s);
 	sci_free_dma(port);
 }