diff --git a/net/netfilter/core.c b/net/netfilter/core.c
index 11a702065bab..ec65ee2953ac 100644
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@ -488,6 +488,9 @@ static void __nf_unregister_net_hook(struct net *net, int pf,
 	struct nf_hook_entries __rcu **pp;
 	struct nf_hook_entries *p;
 
+	if (reg->dev && dev_net(reg->dev) != net)
+		printk(KERN_INFO "%s: called for a device in different netns\n", __func__);
+
 	pp = nf_hook_entry_head(net, pf, reg->hooknum, reg->dev);
 	if (!pp)
 		return;