From a796ce4827fcbbb269f9e105f6b852b0dec85217 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Tue, 26 Mar 2013 10:49:55 +0800 Subject: [PATCH] USB: serial: fix hang when opening port commit eba0e3c3a0ba7b96f01cbe997680f6a4401a0bfc upstream. Johan's 'fix use-after-free in TIOCMIWAIT' patchset[1] introduces one bug which can cause kernel hang when opening port. This patch initialized the 'port->delta_msr_wait' waitqueue head to fix the bug which is introduced in 3.9-rc4. [1], http://marc.info/?l=linux-usb&m=136368139627876&w=2 Signed-off-by: Ming Lei Acked-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/usb/serial/usb-serial.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c index 2482d5edc670..850faa447000 100644 --- a/drivers/usb/serial/usb-serial.c +++ b/drivers/usb/serial/usb-serial.c @@ -905,6 +905,7 @@ int usb_serial_probe(struct usb_interface *interface, port->port.ops = &serial_port_ops; port->serial = serial; spin_lock_init(&port->lock); + init_waitqueue_head(&port->delta_msr_wait); /* Keep this for private driver use for the moment but should probably go away */ INIT_WORK(&port->work, usb_serial_port_work); -- 2.39.2