From: Thomas Petazzoni Date: Thu, 16 Jun 2016 14:48:52 +0000 (+0200) Subject: serial: mvebu-uart: free the IRQ in ->shutdown() X-Git-Tag: v4.6.7~7 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7fbb33362c693b6e991f9ff4d08cb162bae683d2;p=thirdparty%2Fkernel%2Fstable.git serial: mvebu-uart: free the IRQ in ->shutdown() commit c2c1659b4f8f9e19fe82a4fd06cca4b3d59090ce upstream. As suggested by the serial port infrastructure documentation, the IRQ is requested in ->startup(). However, it is never freed in the ->shutdown() hook. With simple systems that open the serial port once for all and always have at least one process that keep the serial port opened, there was no problem. But with a more complicated system (*cough* systemd *cough*), the serial port is opened/closed many times, which at some point no processes having the serial port open at all. Due to this ->startup() gets called again, tries to request_irq() again, which fails. Fixes: 30530791a7a0 ("serial: mvebu-uart: initial support for Armada-3700 serial port") Cc: Ofer Heifetz Signed-off-by: Thomas Petazzoni Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c index 0ff27818bb87d..25b9f178c8d36 100644 --- a/drivers/tty/serial/mvebu-uart.c +++ b/drivers/tty/serial/mvebu-uart.c @@ -299,6 +299,8 @@ static int mvebu_uart_startup(struct uart_port *port) static void mvebu_uart_shutdown(struct uart_port *port) { writel(0, port->membase + UART_CTRL); + + free_irq(port->irq, port); } static void mvebu_uart_set_termios(struct uart_port *port,