Re: [patch net-next 1/4] net: introduce new priv_flag indicating iface capable of change mac when running

[Jiri Pirko <jpirko@redhat.com>]

Fri, Jun 29, 2012 at 12:17:34AM CEST, bhutchings@solarflare.com wrote:
>On Thu, 2012-06-28 at 16:10 +0200, Jiri Pirko wrote:
>> Introduce IFF_LIFE_ADDR_CHANGE priv_flag and use it to disable
>> netif_running() check in eth_mac_addr()
>>
>> Signed-off-by: Jiri Pirko <jpirko@redhat.com>
>> ---
>>  include/linux/if.h |    2 ++
>>  net/ethernet/eth.c |    2 +-
>>  2 files changed, 3 insertions(+), 1 deletion(-)
>> 
>> diff --git a/include/linux/if.h b/include/linux/if.h
>> index f995c66..fd9ee7c 100644
>> --- a/include/linux/if.h
>> +++ b/include/linux/if.h
>> @@ -81,6 +81,8 @@
>>  #define IFF_UNICAST_FLT	0x20000		/* Supports unicast filtering	*/
>>  #define IFF_TEAM_PORT	0x40000		/* device used as team port */
>>  #define IFF_SUPP_NOFCS	0x80000		/* device supports sending custom FCS */
>> +#define IFF_LIFE_ADDR_CHANGE 0x100000	/* device supports hardware address
>> +					 * change when it's running */
>[...]
>
>Any device that has IFF_UNICAST_FLT can update the unicast MAC filter
>while it's running; doesn't that go hand-in-hand with being able to
>handle changes to the primary MAC address?  Is the new flag really
>necessary at all?

Hmm, this makes sense. But, can you guarantee that all devices behave like this?

Also, there are many devices that does not support unicast filtering
and yet they support updating mac adress while running.

Jirka

>
>Ben.
>
>-- 
>Ben Hutchings, Staff Engineer, Solarflare
>Not speaking for my employer; that's the marketing department's job.
>They asked us to note that Solarflare product names are trademarked.
>