Merge remote-tracking branch 'lts/linux-4.4.y' into linux-linaro-lsk-v4.4

1 files changed, 16 insertions, 0 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 9efbdb3ff78a..de4ed2b5a221 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3722,6 +3722,22 @@ static inline struct sk_buff *handle_ing(struct sk_buff *skb,
 }
 
 /**
+ *	netdev_is_rx_handler_busy - check if receive handler is registered
+ *	@dev: device to check
+ *
+ *	Check if a receive handler is already registered for a given device.
+ *	Return true if there one.
+ *
+ *	The caller must hold the rtnl_mutex.
+ */
+bool netdev_is_rx_handler_busy(struct net_device *dev)
+{
+	ASSERT_RTNL();
+	return dev && rtnl_dereference(dev->rx_handler);
+}
+EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy);
+
+/**
  *	netdev_rx_handler_register - register receive handler
  *	@dev: device to register a handler for
  *	@rx_handler: receive handler to register