> > But if a driver does make the call, it should be careful to ensure that > > the call happens _after_ the driver is finished using the interface-data > > pointer. For example, after all outstanding URBs have completed, if the > > completion handlers will need to call usb_get_intfdata(). > > ACK. I understand that it should be called *after* the completion of > any ongoing task. What sometimes gets people is /sys, /proc. etc. A process can have such a file open when the device is unplugged. If the read needs to make use of your private data structure, you need to guarantee it still exists. Ideally the core needs to wait and not call the disconnect until all such files are closed. Probably the USB core does, it is such an obvious issue, but i have no knowledge of USB. Andrew
