NETLINK_CB(skb).pid = 0; /* from kernel */
NETLINK_CB(skb).dst_group = 0; /* unicast */
netlink_unicast(sk, skb, pid, MSG_DONTWAIT);
NETLINK_CB(skb).pid = 0; /* from kernel */
NETLINK_CB(skb).dst_group = 0; /* unicast */
netlink_unicast(sk, skb, pid, MSG_DONTWAIT);