From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next] gro: should aggregate frames without DF
Date: Fri, 31 May 2013 14:12:13 -0700
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Cc: David Miller <davem@davemloft.net>,
	netdev <netdev@vger.kernel.org>, Jerry Chu <hkchu@google.com>,
	Herbert Xu <herbert@gondor.apana.org.au>
To: Ben Hutchings <bhutchings@solarflare.com>
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On Fri, 2013-05-31 at 21:09 +0100, Ben Hutchings wrote:

> But this results in ignoring the actual offset bits of frag_off!
> We should allow merging only if all packets have frag_off == IP_DF or
> all have frag_off == 0.  The first assignment of flush therefore still
> needs to check the combined id/frag_off word, but using (id & ~IP_DF)
> instead of (id ^ IP_DF).

You're right, I guess I wanted too much getting rid of black magic in
this code ;)

I'll send a v2