From: Jukka Rissanen Date: Tue, 28 Oct 2014 15:16:48 +0000 (+0200) Subject: Bluetooth: 6lowpan: Fix lockdep splats X-Git-Tag: v3.19-rc1~118^2~234^2~3^2~42 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=df092306d688438b39f7d433f24e091fa387afaf;p=karo-tx-linux.git Bluetooth: 6lowpan: Fix lockdep splats When a device ndo_start_xmit() calls again dev_queue_xmit(), lockdep can complain because dev_queue_xmit() is re-entered and the spinlocks protecting tx queues share a common lockdep class. Same issue was fixed for ieee802154 in commit "20e7c4e80dcd" Signed-off-by: Jukka Rissanen Signed-off-by: Marcel Holtmann --- diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c index a681247b0aee..7254bddaca2f 100644 --- a/net/bluetooth/6lowpan.c +++ b/net/bluetooth/6lowpan.c @@ -662,7 +662,26 @@ static netdev_tx_t bt_xmit(struct sk_buff *skb, struct net_device *netdev) return err < 0 ? NET_XMIT_DROP : err; } +static struct lock_class_key bt_tx_busylock; +static struct lock_class_key bt_netdev_xmit_lock_key; + +static void bt_set_lockdep_class_one(struct net_device *dev, + struct netdev_queue *txq, + void *_unused) +{ + lockdep_set_class(&txq->_xmit_lock, &bt_netdev_xmit_lock_key); +} + +static int bt_dev_init(struct net_device *dev) +{ + netdev_for_each_tx_queue(dev, bt_set_lockdep_class_one, NULL); + dev->qdisc_tx_busylock = &bt_tx_busylock; + + return 0; +} + static const struct net_device_ops netdev_ops = { + .ndo_init = bt_dev_init, .ndo_start_xmit = bt_xmit, };