--- a/include/linux/netpoll.h	2012-09-18 13:25:15.575750004 -0700
+++ b/include/linux/netpoll.h	2012-09-18 13:29:16.245323347 -0700
@@ -66,10 +66,16 @@ static inline void netpoll_send_skb(stru
 
 
 #ifdef CONFIG_NETPOLL
+extern struct static_key netpoll_needed;
+
 static inline bool netpoll_rx_on(struct sk_buff *skb)
 {
-	struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo);
+	struct netpoll_info *npinfo;
+
+	if (static_key_true(&netpoll_needed))
+		return false;
 
+	npinfo = rcu_dereference_bh(skb->dev->npinfo);
 	return npinfo && (!list_empty(&npinfo->rx_np) || npinfo->rx_flags);
 }
 
@@ -79,12 +85,14 @@ static inline bool netpoll_rx(struct sk_
 	unsigned long flags;
 	bool ret = false;
 
-	local_irq_save(flags);
+	if (static_key_true(&netpoll_needed))
+		return false;
 
-	if (!netpoll_rx_on(skb))
+	local_irq_save(flags);
+	npinfo = rcu_dereference_bh(skb->dev->npinfo);
+	if (!npinfo || (list_empty(&npinfo->rx_np) && !npinfo->rx_flags))
 		goto out;
 
-	npinfo = rcu_dereference_bh(skb->dev->npinfo);
 	spin_lock(&npinfo->rx_lock);
 	/* check rx_flags again with the lock held */
 	if (npinfo->rx_flags && __netpoll_rx(skb, npinfo))
@@ -96,11 +104,15 @@ out:
 	return ret;
 }
 
-static inline int netpoll_receive_skb(struct sk_buff *skb)
+static inline bool netpoll_receive_skb(struct sk_buff *skb)
 {
+	if (static_key_true(&netpoll_needed))
+		return false;
+
 	if (!list_empty(&skb->dev->napi_list))
 		return netpoll_rx(skb);
-	return 0;
+
+	return false;
 }
 
 static inline void *netpoll_poll_lock(struct napi_struct *napi)
@@ -139,9 +151,9 @@ static inline bool netpoll_rx_on(struct
 {
 	return false;
 }
-static inline int netpoll_receive_skb(struct sk_buff *skb)
+static inline bool netpoll_receive_skb(struct sk_buff *skb)
 {
-	return 0;
+	return false;
 }
 static inline void *netpoll_poll_lock(struct napi_struct *napi)
 {
--- a/net/core/netpoll.c	2012-09-18 13:25:15.575750004 -0700
+++ b/net/core/netpoll.c	2012-09-18 13:26:44.330855089 -0700
@@ -67,6 +67,8 @@ module_param(carrier_timeout, uint, 0644
 #define np_notice(np, fmt, ...)				\
 	pr_notice("%s: " fmt, np->name, ##__VA_ARGS__)
 
+struct static_key netpoll_needed __read_mostly;
+
 static void queue_process(struct work_struct *work)
 {
 	struct netpoll_info *npinfo =
@@ -786,6 +788,8 @@ int __netpoll_setup(struct netpoll *np,
 		npinfo->rx_flags |= NETPOLL_RX_ENABLED;
 		list_add_tail(&np->rx, &npinfo->rx_np);
 		spin_unlock_irqrestore(&npinfo->rx_lock, flags);
+
+		static_key_slow_inc(&netpoll_needed);
 	}
 
 	/* last thing to do is link it to the net device structure */
@@ -926,8 +930,10 @@ void __netpoll_cleanup(struct netpoll *n
 	if (!list_empty(&npinfo->rx_np)) {
 		spin_lock_irqsave(&npinfo->rx_lock, flags);
 		list_del(&np->rx);
-		if (list_empty(&npinfo->rx_np))
+		if (list_empty(&npinfo->rx_np)) {
 			npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
+			static_key_slow_dec(&netpoll_needed);
+		}
 		spin_unlock_irqrestore(&npinfo->rx_lock, flags);
 	}