Re: IP Fragmentation

[Amit Kucheria <amitk@ittc.ku.edu>]

On Mon, 4 Feb 2002, A. Ramesh wrote:

>  I am not sure why the kernel allocates 15 more bytes when it creates a fragment packet. The piece of kernel code which does the memory allocated for the new fragment is as follows:
> 
>                  if ((skb2 = alloc_skb(len+hlen+dev->hard_header_len+15,GFP_ATOMIC)) == NULL) {
>                          NETDEBUG(printk(KERN_INFO "IP: frag: no memory for new fragment!\n"));
>                          err = -ENOMEM;
>                          goto fail;
>                  }
> 
> -Ramesh

Its for word (2-byte) alignment of skb i think. See alloc_skb()

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                  Amit Kucheria
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         University of Kansas @ Lawrence
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