serial: core: Use proper spinlock flavor in uart_close()

uart_close() runs in non-atomic context only; use
spin_lock/unlock_irq instead of saving the interrupt state (which
== on).

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Peter Hurley 2015-07-31 16:59:51 -04:00 committed by Greg Kroah-Hartman
parent 2a0e5ef6cf
commit 6fb98fb303

View File

@ -1377,7 +1377,6 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
struct uart_state *state = tty->driver_data;
struct tty_port *port;
struct uart_port *uport;
unsigned long flags;
if (!state) {
struct uart_driver *drv = tty->driver->driver_state;
@ -1403,10 +1402,9 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
* disable the receive line status interrupts.
*/
if (port->flags & ASYNC_INITIALIZED) {
unsigned long flags;
spin_lock_irqsave(&uport->lock, flags);
spin_lock_irq(&uport->lock);
uport->ops->stop_rx(uport);
spin_unlock_irqrestore(&uport->lock, flags);
spin_unlock_irq(&uport->lock);
/*
* Before we drop DTR, make sure the UART transmitter
* has completely drained; this is especially
@ -1419,17 +1417,17 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
uart_shutdown(tty, state);
tty_port_tty_set(port, NULL);
spin_lock_irqsave(&port->lock, flags);
spin_lock_irq(&port->lock);
if (port->blocked_open) {
spin_unlock_irqrestore(&port->lock, flags);
spin_unlock_irq(&port->lock);
if (port->close_delay)
msleep_interruptible(jiffies_to_msecs(port->close_delay));
spin_lock_irqsave(&port->lock, flags);
spin_lock_irq(&port->lock);
} else if (!uart_console(uport)) {
spin_unlock_irqrestore(&port->lock, flags);
spin_unlock_irq(&port->lock);
uart_change_pm(state, UART_PM_STATE_OFF);
spin_lock_irqsave(&port->lock, flags);
spin_lock_irq(&port->lock);
}
/*
@ -1437,7 +1435,7 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
*/
clear_bit(ASYNCB_NORMAL_ACTIVE, &port->flags);
clear_bit(ASYNCB_CLOSING, &port->flags);
spin_unlock_irqrestore(&port->lock, flags);
spin_unlock_irq(&port->lock);
wake_up_interruptible(&port->open_wait);
wake_up_interruptible(&port->close_wait);