On Wed, 29 Apr 2009, Alan Stern wrote: > Looks like the ftdi_sio driver doesn't use proper reference counting > for its private data structure. Does this patch help? Oops, I forgot to initialize the kref. Try this patch instead. Alan Stern Index: 2.6.30-rc3/drivers/usb/serial/ftdi_sio.c =================================================================== --- 2.6.30-rc3.orig/drivers/usb/serial/ftdi_sio.c +++ 2.6.30-rc3/drivers/usb/serial/ftdi_sio.c @@ -56,6 +56,7 @@ static __u16 vendor = FTDI_VID; static __u16 product; struct ftdi_private { + struct kref kref; ftdi_chip_type_t chip_type; /* type of device, either SIO or FT8U232AM */ int baud_base; /* baud base clock for divisor setting */ @@ -1352,6 +1353,7 @@ static int ftdi_sio_port_probe(struct us return -ENOMEM; } + kref_init(&priv->kref); spin_lock_init(&priv->rx_lock); spin_lock_init(&priv->tx_lock); init_waitqueue_head(&priv->delta_msr_wait); @@ -1468,6 +1470,13 @@ static void ftdi_shutdown(struct usb_ser dbg("%s", __func__); } +static void ftdi_sio_priv_release(struct kref *k) +{ + struct ftdi_private *priv = container_of(k, struct ftdi_private, kref); + + kfree(priv); +} + static int ftdi_sio_port_remove(struct usb_serial_port *port) { struct ftdi_private *priv = usb_get_serial_port_data(port); @@ -1482,7 +1491,7 @@ static int ftdi_sio_port_remove(struct u if (priv) { usb_set_serial_port_data(port, NULL); - kfree(priv); + kref_put(&priv->kref, ftdi_sio_priv_release); } return 0; @@ -1547,7 +1556,8 @@ static int ftdi_open(struct tty_struct * dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __func__, result); - + else + kref_get(&priv->kref); return result; } /* ftdi_open */ @@ -1589,11 +1599,11 @@ static void ftdi_close(struct tty_struct mutex_unlock(&port->serial->disc_mutex); /* cancel any scheduled reading */ - cancel_delayed_work(&priv->rx_work); - flush_scheduled_work(); + cancel_delayed_work_sync(&priv->rx_work); /* shutdown our bulk read */ usb_kill_urb(port->read_urb); + kref_put(&priv->kref, ftdi_sio_priv_release); } /* ftdi_close */ -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html