> What is the proper way to avoid a race with HUP in tty->ops->write, > chars_in_buffer, ntty_write_room and possibly others? You shouldn't need to do anything in those cases as tty and tty->driver_data won't be going anywhere. port->tty may go NULL and the IRQ handlers etc need to get the refs properly and keep refs when needed so the tty isn't freed under them, but that *should* be all that is needed if the logic is right. > I looked into the drivers, moxa tests tty->driver_data (why? [1]), mxser > does nothing as well as rocket and many others. What is the reference > driver I should look into? I think its a delusion from early drivers that never got sorted > > [1] Perhaps leftover from when moxa_shutdown used to NULL it. > > I don't see why the driver should care at all. It has a tty, > tty->driver_data and thus all the HW info. So it should ignore the race, > i.e. test nothing, right? Yes -- To unsubscribe from this list: send the line "unsubscribe linux-ppp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html