From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next] store complete hash type information in socket
 buffer...
Date: Wed, 17 Feb 2016 22:30:01 +0100
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	 <20160217.154432.788293606088459412.davem@davemloft.net>
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	tom@herbertland.com
To: David Miller <davem@davemloft.net>
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On mer., 2016-02-17 at 15:44 -0500, David Miller wrote:
> From: Paul Durrant <paul.durrant@citrix.com>
> Date: Mon, 15 Feb 2016 08:32:08 +0000
> 
> > ...rather than a boolean merely indicating a canonical L4 hash.
> > 
> > skb_set_hash() takes a hash type (from enum pkt_hash_types) as an
> > argument but information is lost since only a single bit in the skb
> > stores whether that hash type is PKT_HASH_TYPE_L4 or not. By using
> > two bits it's possible to store the complete hash type information.
> > 
> > Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
> 
> Tom and/or Eric, please have a look at this.

I guess my question is simply 'why do we need this' ?

Consuming a bit in our precious sk_buff is not something we want for
some obscure feature.