From a1c33952b729eba4cedb8dbe54765921f2b3062f Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Wed, 7 Oct 2009 11:01:38 +0200 Subject: [PATCH] USB: serial: fix race between unthrottle and completion handler in visor usb:usbserial:visor: fix race between unthrottle and completion handler visor_unthrottle() mustn't resubmit the URB unconditionally as the URB may still be running. the same bug as opticon. Signed-off-by: Oliver Neukum Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/visor.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c index b9341f0..ad1f923 100644 --- a/drivers/usb/serial/visor.c +++ b/drivers/usb/serial/visor.c @@ -595,20 +595,23 @@ static void visor_unthrottle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct visor_private *priv = usb_get_serial_port_data(port); - int result; + int result, was_throttled; dbg("%s - port %d", __func__, port->number); spin_lock_irq(&priv->lock); priv->throttled = 0; + was_throttled = priv->actually_throttled; priv->actually_throttled = 0; spin_unlock_irq(&priv->lock); - port->read_urb->dev = port->serial->dev; - result = usb_submit_urb(port->read_urb, GFP_KERNEL); - if (result) - dev_err(&port->dev, - "%s - failed submitting read urb, error %d\n", + if (was_throttled) { + port->read_urb->dev = port->serial->dev; + result = usb_submit_urb(port->read_urb, GFP_KERNEL); + if (result) + dev_err(&port->dev, + "%s - failed submitting read urb, error %d\n", __func__, result); + } } static int palm_os_3_probe(struct usb_serial *serial, -- 2.7.4