From mboxrd@z Thu Jan  1 00:00:00 1970
From: Simon Horman <horms@verge.net.au>
Subject: Re: [PATCH 19/25] mlx4: Randomizing mac addresses for slaves
Date: Fri, 6 Nov 2009 15:06:24 +1100
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Cc: Liran Liss <liranl@mellanox.co.il>,
	Or Gerlitz <or.gerlitz@gmail.com>,
	Yevgeny Petrilin <yevgenyp@mellanox.co.il>,
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	Tziporet Koren <tziporet@mellanox.co.il>
To: Roland Dreier <rdreier@cisco.com>
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On Thu, Nov 05, 2009 at 07:58:12AM -0800, Roland Dreier wrote:
> 
>  > This approach seems to be common practice now (e.g., drivers/net/igb/igb_main.c:1332).
>  > In any case, the user can change the randomized mac.
> 
> igb uses the full output of random_ether_addr().  I'd be fine with
> that.  However setting the OUI means you only get 24 bits of randomness
> which makes a collision a lot more likely.

IIRC that was precisely why the OUI isn't used for the igb driver.

Perhaps some infrastructure (by which I mean a random_mac() function)
is warranted so at least this discussion can be concentrated around that
rather than repeating it for each driver that needs random mac addresses.