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 <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index a681247..7254bdda 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -662,7 +662,26 @@
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,
};