Re: tun: Use netif_receive_skb instead of netif_rx

Herbert Xu
2010-05-20T05:21:19Z

On Thu, May 20, 2010 at 07:15:07AM +0200, Eric Dumazet wrote:
>
> I find this very biased, sorry.
>
> In fact, fd passing is just fine today, if we consider that we classify
> packets using the identity of the process *using* the fd, not the one
> that *created* it.
>
> Now your patch changes this, to the reverse, and you justify the caching
> effect on socket. Sorry, this must be too convoluted for me.

I'm sorry you find this convoluted, but using the sending process's
classid is inherently broken.

Here is why: consider a TCP socket shared by two processes with
different classids both writing data to it. Now suppose further
that each writes just one byte, which is then coalesced into a
single skb.

Whose classid should we use on the resulting skb?

Cheers,
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