From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shirley Ma <mashirle@us.ibm.com>
Subject: Re: [RFC PATCH 2/2] macvtap: TX zero copy between guest and host
 kernel
Date: Wed, 29 Sep 2010 07:31:29 -0700
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Cc: Arnd Bergmann <arnd@arndb.de>, Avi Kivity <avi@redhat.com>,
	"Xin, Xiaohui" <xiaohui.xin@intel.com>,
	David Miller <davem@davemloft.net>, netdev@vger.kernel.org,
	kvm@vger.kernel.org, linux-kernel@vger.kernel.org
To: "Michael S. Tsirkin" <mst@redhat.com>
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On Wed, 2010-09-29 at 10:16 +0200, Michael S. Tsirkin wrote:
> If you look at dev_hard_start_xmit you will see a call
> to skb_orphan_try which often calls the skb destructor.
> So I suspect this is almost equivalent to your original patch,
> and has the same correctness issue.

I forgot to mention, in skb_orphan_try, I still kept the skb->sk
reference to sk, I assign skb->sk to NULL when the DMA done.

Thanks
Shirley