From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-2.6] net: copy userspace buffers on device
 forwarding
Date: Thu, 15 Sep 2011 15:08:22 -0400 (EDT)
Message-ID: <20110915.150822.1432876015378023873.davem@davemloft.net>
References: <20110831180328.GA22016@redhat.com>
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Cc: herbert@gondor.hengli.com.au, eric.dumazet@gmail.com,
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From: "Michael S. Tsirkin" <mst@redhat.com>
Date: Wed, 31 Aug 2011 21:03:29 +0300

> dev_forward_skb loops an skb back into host networking
> stack which might hang on the memory indefinitely.
> In particular, this can happen in macvtap in bridged mode.
> Copy the userspace fragments to avoid blocking the
> sender in that case.
> 
> As this patch makes skb_copy_ubufs extern now,
> I also added some documentation and made it clear
> the SKBTX_DEV_ZEROCOPY flag automatically instead
> of doing it in all callers. This can be made into a separate
> patch if people feel it's worth it.
> 
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Applied.