On Fri, 10 Aug 2012, Huajun Li wrote: > With commit 0998d0631001288a5974afc0b2a5f568bcdecb4d, driver_data is > cleared after driver is unbound. > So from now on, it's not suitable to maintain serial port private data > by driver core, because some usb serial drivers, > such as usb_wwan, need retrieve port private data(in disconnect() and > release() callbacks ) even after the driver is unbound. > This will cause NULL pointer reference oops. > > Let usb_serial_port maintain port private data to fix the issue. Wouldn't it be better to fix the serial drivers instead? Some changes in this direction have already been proposed for usb_wwan. Alan Stern -- 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