USB: serial: fix USB serial fix kfifo_len locking
This patch fix a possible race bug in drivers/usb/serial/generic with
the new kfifo API.
Please apply it to the 2.6.33-rc* tree.
Signed-off-by: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c
index f1ea3a3..5ce033a 100644
--- a/drivers/usb/serial/generic.c
+++ b/drivers/usb/serial/generic.c
@@ -386,12 +386,12 @@
dbg("%s - port %d", __func__, port->number);
- if (serial->type->max_in_flight_urbs) {
- spin_lock_irqsave(&port->lock, flags);
+ spin_lock_irqsave(&port->lock, flags);
+ if (serial->type->max_in_flight_urbs)
chars = port->tx_bytes_flight;
- spin_unlock_irqrestore(&port->lock, flags);
- } else if (serial->num_bulk_out)
+ else if (serial->num_bulk_out)
chars = kfifo_len(&port->write_fifo);
+ spin_unlock_irqrestore(&port->lock, flags);
dbg("%s - returns %d", __func__, chars);
return chars;