USB: fix errornous assumption in the usb serial framework revealed by iuu_phoenix
the iuu_phoenix driver submits another URB from a completion handler.
This dictates a certain order of calls to usb_kill_urb() in kill_traffic().
As other drivers may do it the other way round, we need to use both
orders in kill_traffic().
This patch does so and should be merged before iuu_phoenix is merged.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 9bf01a5..26e015c 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -578,6 +578,17 @@
{
usb_kill_urb(port->read_urb);
usb_kill_urb(port->write_urb);
+ /*
+ * This is tricky.
+ * Some drivers submit the read_urb in the
+ * handler for the write_urb or vice versa
+ * this order determines the order in which
+ * usb_kill_urb() must be used to reliably
+ * kill the URBs. As it is unknown here,
+ * both orders must be used in turn.
+ * The call below is not redundant.
+ */
+ usb_kill_urb(port->read_urb);
usb_kill_urb(port->interrupt_in_urb);
usb_kill_urb(port->interrupt_out_urb);
}