From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: macvtap: Limit packet queue length
Date: Thu, 22 Jul 2010 12:58:08 -0700 (PDT)
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From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Fri, 23 Jul 2010 00:07:31 +0800

> On Thu, Jul 22, 2010 at 08:59:58AM -0700, Shirley Ma wrote:
>> On Thu, 2010-07-22 at 14:41 +0800, Herbert Xu wrote:
>> >  {
>> >         struct macvtap_queue *q = macvtap_get_queue(dev, skb);
>> >         if (!q)
>> > -               return -ENOLINK;
>> > +               goto drop;
>> > +
>> > +       if (skb_queue_len(&q->sk.sk_receive_queue) >=
>> > dev->tx_queue_len)
>> > +               goto drop;
>> > 
>> 
>> Do we need to orphan skb here, just like tun?
> 
> We could, but that is orthogonal to the problem at hand so feel
> free to do that in another patch.

These days, the stack pre-orphans all packets sent to ->ndo_start_xmit()
in dev_hard_start_xmit() as long as socket based TX timestamping is not
active for the packet.