From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH v2] net: af_packet: don't call tpacket_destruct_skb()
 until the skb is sent out
Date: Sun, 12 Sep 2010 14:13:49 +0200
Message-ID: <20100912121349.GD22982@redhat.com>
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Cc: "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <eric.dumazet@gmail.com>,
	Oliver Hartkopp <socketcan@hartkopp.net>,
	netdev@vger.kernel.org
To: Changli Gao <xiaosuo@gmail.com>
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On Sat, Sep 11, 2010 at 11:23:23AM +0800, Changli Gao wrote:
> @@ -799,7 +806,9 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
>  
>  	memcpy((struct skb_shared_info *)(data + size),
>  	       skb_shinfo(skb),
> -	       offsetof(struct skb_shared_info, frags[skb_shinfo(skb)->nr_frags]));
> +	       offsetof(struct skb_shared_info,
> +			frags[skb_shinfo(skb)->nr_frags]));
> +	skb_shinfo(skb)->destructor = NULL;
>  
>  	/* Check if we can avoid taking references on fragments if we own
>  	 * the last reference on skb->head. (see skb_release_data())

So it looks like pskb_expand_head will prevent the shinfo desctructor
from being called, ever? If so, won't this break af_packet?

-- 
MST