From ebe937f74b8a72cf3ceeae5c2194a160bb092901 Mon Sep 17 00:00:00 2001 From: Gianluca Anzolin Date: Mon, 29 Jul 2013 17:08:09 +0200 Subject: [PATCH] Bluetooth: Remove the device from the list in the destructor The current code removes the device from the device list in several places. Do it only in the destructor instead and in the error path of rfcomm_add_dev() if the device couldn't be initialized. Signed-off-by: Gianluca Anzolin Reviewed-by: Peter Hurley Signed-off-by: Gustavo Padovan --- net/bluetooth/rfcomm/tty.c | 27 ++++++--------------------- 1 file changed, 6 insertions(+), 21 deletions(-) diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c index cd7ff370be38..9c0e142041bd 100644 --- a/net/bluetooth/rfcomm/tty.c +++ b/net/bluetooth/rfcomm/tty.c @@ -76,13 +76,6 @@ static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig); /* ---- Device functions ---- */ -/* - * The reason this isn't actually a race, as you no doubt have a little voice - * screaming at you in your head, is that the refcount should never actually - * reach zero unless the device has already been taken off the list, in - * rfcomm_dev_del(). And if that's not true, we'll hit the BUG() in - * rfcomm_dev_destruct() anyway. - */ static void rfcomm_dev_destruct(struct tty_port *port) { struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port); @@ -90,10 +83,9 @@ static void rfcomm_dev_destruct(struct tty_port *port) BT_DBG("dev %p dlc %p", dev, dlc); - /* Refcount should only hit zero when called from rfcomm_dev_del() - which will have taken us off the list. Everything else are - refcounting bugs. */ - BUG_ON(!list_empty(&dev->list)); + spin_lock(&rfcomm_dev_lock); + list_del(&dev->list); + spin_unlock(&rfcomm_dev_lock); rfcomm_dlc_lock(dlc); /* Detach DLC if it's owned by this dev */ @@ -282,7 +274,9 @@ out: dev->id, NULL); if (IS_ERR(dev->tty_dev)) { err = PTR_ERR(dev->tty_dev); + spin_lock(&rfcomm_dev_lock); list_del(&dev->list); + spin_unlock(&rfcomm_dev_lock); goto free; } @@ -315,10 +309,6 @@ static void rfcomm_dev_del(struct rfcomm_dev *dev) } spin_unlock_irqrestore(&dev->port.lock, flags); - spin_lock(&rfcomm_dev_lock); - list_del_init(&dev->list); - spin_unlock(&rfcomm_dev_lock); - tty_port_put(&dev->port); } @@ -750,13 +740,8 @@ static void rfcomm_tty_close(struct tty_struct *tty, struct file *filp) dev->port.tty = NULL; rfcomm_dlc_unlock(dev->dlc); - if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags)) { - spin_lock(&rfcomm_dev_lock); - list_del_init(&dev->list); - spin_unlock(&rfcomm_dev_lock); - + if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags)) tty_port_put(&dev->port); - } } else spin_unlock_irqrestore(&dev->port.lock, flags); -- 2.30.2