Hi, can someone tell me what the path of an ip packet is after you call ip_send (skb)? The problem I am facing is: When i call ip_send to send out the packet, the function returns sucessfully, but soon after this, i get an skb_under_panic - some function down below is probably trying to push back the skb->data to attach the hardware header, and goes back beyond skb->head. How does ip_send return successfully, but then I get an error? I know that ip_send ultimately calls dev_queue_xmit, but I lost track after that. Does this function only queue up the packet for transmission and return? Am i right in assuming that the actual sending of the packet doesnt take place in the same "thread" of control? (happens sometime afterwards, asynchronously?) When is the packet scheduled for actual transission? Who builds the hardware header? - thats where the under panic is probably being caused. TIA Akshay __________________________________________________ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org