From: Casey Leedom <leedom@chelsio.com>
Organization: Chelsio Communications, Inc.
To: Andy Gospodarek <andy@greyhouse.net>
Subject: Re: [PATCH net-next] sysfs: add entry to indicate network interfaces with random MAC address
Date: Wed, 21 Jul 2010 09:34:27 -0700
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Cc: Harald Hoyer <harald@redhat.com>, David Miller <davem@davemloft.net>,
        shemminger@vyatta.com, bhutchings@solarflare.com, sassmann@redhat.com,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org, gospo@redhat.com,
        gregory.v.rose@intel.com, alexander.h.duyck@intel.com
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| From: Andy Gospodarek <andy@greyhouse.net>
| Date: Wednesday, July 21, 2010 08:07 am
| 
| Agreed.  The subtle difference between a locally assigned address that
| is persistent and one that is random would be helpful.

  And just to point out that this case _does_ exist: the igb/igbvf drivers use 
random_ether_addr() to generate a random, locally assigned MAC address for the 
PCI-E SR-IOV Virtual Function MAC Addresses while the cxgb4/cxgb4vf drivers use 
a persistent, non-random locally assigned MAC Addresses.

  Note that I am neither arguing for nor against the proposal.  I'm just 
pointing out an existence case for the distinction.  And yes, bit 1 being set in 
the first octet of a MAC address for locally assigned MAC Addresses is part of 
the IEEE 802 specification just as bit 0 being set in the same octet indicates 
that it's a multi-station address.

Casey
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