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From: Gavin Atkinson <gavin@FreeBSD.org>
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To: Gleb Smirnoff <glebius@FreeBSD.org>
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Subject: Re: [head up!] WiFi drivers changes
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On Thu, 6 Aug 2015, Gleb Smirnoff wrote:
>   As part of the "opaque ifnet project" [1], all 802.11 (WiFi) drivers
> undergo change of not being an interface anymore. Historically in FreeBSD
> 802.11 stack, 802.11 devices called if_attach() and created an interface.
> Later this was generalized and real functioning interface is created by
> net80211 stack. However, remnant of parent interface remained. If you
> are running Intel Centrino wireless, then you got iwn0 interface and
> wlan0 interface. However, the former doesn't do anything. You can't
> assign addresses to it or modify any of it parameters. Or you can
> modify them, but that affects nothing.

You could, however, change the Ethernet address of the underlying 
interface before creating the wlanX interfaces, which woud then be used by 
the child interfaces.  This has traditionally been the only way you could 
change the Ethernet interface of a wifi device - changing it after 
creating the wlanX interface does not work.

How will this be done in the new world?

Thanks,

Gavin