[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20220607180317.482354-14-sashal@kernel.org>
Date: Tue, 7 Jun 2022 14:03:09 -0400
From: Sasha Levin <sashal@...nel.org>
To: linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc: John Ogness <john.ogness@...utronix.de>,
Marek Szyprowski <m.szyprowski@...sung.com>,
Petr Mladek <pmladek@...e.com>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Sasha Levin <sashal@...nel.org>, agross@...nel.org,
bjorn.andersson@...aro.org, jirislaby@...nel.org,
linux-arm-msm@...r.kernel.org, linux-serial@...r.kernel.org
Subject: [PATCH AUTOSEL 4.9 14/19] serial: msm_serial: disable interrupts in __msm_console_write()
From: John Ogness <john.ogness@...utronix.de>
[ Upstream commit aabdbb1b7a5819e18c403334a31fb0cc2c06ad41 ]
__msm_console_write() assumes that interrupts are disabled, but
with threaded console printers it is possible that the write()
callback of the console is called with interrupts enabled.
Explicitly disable interrupts using local_irq_save() to preserve
the assumed context.
Reported-by: Marek Szyprowski <m.szyprowski@...sung.com>
Reviewed-by: Petr Mladek <pmladek@...e.com>
Signed-off-by: John Ogness <john.ogness@...utronix.de>
Link: https://lore.kernel.org/r/20220506213324.470461-1-john.ogness@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
drivers/tty/serial/msm_serial.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
index c284e61ed4fc..33d035f9fded 100644
--- a/drivers/tty/serial/msm_serial.c
+++ b/drivers/tty/serial/msm_serial.c
@@ -1578,6 +1578,7 @@ static inline struct uart_port *msm_get_port_from_line(unsigned int line)
static void __msm_console_write(struct uart_port *port, const char *s,
unsigned int count, bool is_uartdm)
{
+ unsigned long flags;
int i;
int num_newlines = 0;
bool replaced = false;
@@ -1595,6 +1596,8 @@ static void __msm_console_write(struct uart_port *port, const char *s,
num_newlines++;
count += num_newlines;
+ local_irq_save(flags);
+
if (port->sysrq)
locked = 0;
else if (oops_in_progress)
@@ -1640,6 +1643,8 @@ static void __msm_console_write(struct uart_port *port, const char *s,
if (locked)
spin_unlock(&port->lock);
+
+ local_irq_restore(flags);
}
static void msm_console_write(struct console *co, const char *s,
--
2.35.1
Powered by blists - more mailing lists