Apparently, my earlier reply was lost, trying again: > 2. You must not do IO after returning from > disconnect
Does usb_kill_urb count as "IO"? Many drivers call it from their shutdown routines, which may be called after disconnect. > It is perfectly valid to do (in pseudocode) > > disconnect: > lock() > device->disconnect_flag = 1; > unlock() > rest() > put() > > io-method: > lock() > if (device->disconnect_flag) > goto err_no_dev; > io() > unlock() > Yes, this is similar to the mutex, which you added in your earlier patch. My concern is that calling external functions, such as shutdown, may cause a deadlock if any of them will synchronize with TTY stack. I think that safer way to use a lock or a mutex is to protect short pieces of code, such as usb_serial_get_by_index or get_free_serial. John __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
