From: Peter Hurley <peter@hurleysoftware.com>
Date: Wed, 5 Nov 2014 18:11:44 +0000 (-0500)
Subject: serial: Take uart port lock for direct *_enable_ms()
X-Git-Tag: v3.19-rc1~79^2~71
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=d41510ce2f071c9ccb1903d7a5135443a57dbe4e;p=linux.git

serial: Take uart port lock for direct *_enable_ms()

Three UART drivers (8250, atmel & amba-pl010) directly call their
enable_ms() method; the uart port lock must be acquired before
any h/w programming.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 116b5a75f1af..f0f35e782bc3 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -2613,7 +2613,9 @@ serial8250_set_ldisc(struct uart_port *port, struct ktermios *termios)
 {
 	if (termios->c_line == N_PPS) {
 		port->flags |= UPF_HARDPPS_CD;
+		spin_lock_irq(&port->lock);
 		serial8250_enable_ms(port);
+		spin_unlock_irq(&port->lock);
 	} else
 		port->flags &= ~UPF_HARDPPS_CD;
 }
diff --git a/drivers/tty/serial/amba-pl010.c b/drivers/tty/serial/amba-pl010.c
index 230bc7a290d5..194108b0de84 100644
--- a/drivers/tty/serial/amba-pl010.c
+++ b/drivers/tty/serial/amba-pl010.c
@@ -483,7 +483,9 @@ static void pl010_set_ldisc(struct uart_port *port, struct ktermios *termios)
 {
 	if (termios->c_line == N_PPS) {
 		port->flags |= UPF_HARDPPS_CD;
+		spin_lock_irq(&port->lock);
 		pl010_enable_ms(port);
+		spin_unlock_irq(&port->lock);
 	} else
 		port->flags &= ~UPF_HARDPPS_CD;
 }
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 6a1d960e2e82..e67cb3831280 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -2060,7 +2060,9 @@ static void atmel_set_ldisc(struct uart_port *port, struct ktermios *termios)
 {
 	if (termios->c_line == N_PPS) {
 		port->flags |= UPF_HARDPPS_CD;
+		spin_lock_irq(&port->lock);
 		atmel_enable_ms(port);
+		spin_unlock_irq(&port->lock);
 	} else {
 		port->flags &= ~UPF_HARDPPS_CD;
 	}