Hi, I am extremely sorry to bother this group with this message. But I am really unable to understand the following. So it would be very kind of you if you clarify this. In 2.2.16, in the function alloc_skb(), atomic_set(skb_datarefp(skb),1) is there. Now skb_datarefp() returns skb->end casted in (atomic_t *) type. And atomic_set here setting it to 1. But before atomic_set() is called in alloc_skb(), skb->end is set to data+size. Now my question is what is the purpose of calling atomic_set()? regards sourav - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/