Subject: Re: [PATCH net-next] sysfs: add entry to indicate network interfaces with random MAC address

From: Harald Hoyer <[email-masked]>
Date: Wed, 21 Jul 2010 08:26:27 +0200

On 07/20/2010 11:20 PM, David Miller wrote:
> From: Stephen Hemminger<[email-masked]>
> Date: Tue, 20 Jul 2010 14:18:16 -0700
>
>> No one mentioned that the first octet of an Ethernet address already
>> indicates "software generated" Ethernet address. Per the standard,
>> if bit 1 is set it means address is locally assigned.
>>
>> static inline bool is_locally_assigned_ether(const u8 *addr)
>> {
>> 	return (addr[0]&  0x2) != 0;
>> }
>
> W00t!
>
> Indeed, can udev just use that?  :-)

It already does:
see /lib/udev/rules.d/75-persistent-net-generator.rules