Commit d2b39182 authored Sep 19, 2009 by Alan Cox Committed by Live-CD User Sep 19, 2009

tty: USB hangup is racy



The USB layer uses tty_hangup to deal with unplugs of the physical hardware
(analogous to loss of carrier) and then frees the resources. However the
tty_hangup is asynchronous. As the hangup can sleep we can use tty_vhangup
which is the non async version to avoid freeing resources too early.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

parent 9b80fee1

drivers/usb/serial/usb-serial.c

+1 −4

Original line number	Diff line number	Diff line
		@@ -1161,10 +1161,7 @@ void usb_serial_disconnect(struct usb_interface *interface)
		if (port) {
		struct tty_struct *tty = tty_port_tty_get(&port->port);
		if (tty) {
		/* The hangup will occur asynchronously but
		the object refcounts will sort out all the
		cleanup */
		tty_hangup(tty);
		tty_vhangup(tty);
		tty_kref_put(tty);
		}
		kill_traffic(port);