From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [RFC] about "net: orphan frags on receive" insanity
Date: Wed, 26 Jun 2013 22:22:02 +0300
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To: Eric Dumazet <eric.dumazet@gmail.com>
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On Wed, Jun 26, 2013 at 12:09:24PM -0700, Eric Dumazet wrote:
> On Wed, 2013-06-26 at 21:56 +0300, Michael S. Tsirkin wrote:
> 
> > Well we don't want to duplicate the whole RX path
> > to special-case that, right?
> 
> 
> Whats wrong using a helper ?
> 
> I_Should_cleanup_things(skb)
> {
> 	... // cleanup for these special users trying to reenter stack
> 
> 	netif_rx(skb);
> }
> 

The point is we don't know the final destination of the packet
until it's going through the stack.

We don't want to trigger a copy for all data we get from tun:
we only want to do this if the data has a chance to get
queued somewhere indefinitely.


-- 
MST