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Message-ID: <47aaaccf7d8fb58587f0cfbe38acd18e1420dc9a.camel@sipsolutions.net>
Subject: Re: [PATCH 1/2] nl80211: Add LIVE_ADDR_CHANGE feature
From:   Johannes Berg <johannes@sipsolutions.net>
To:     James Prestwood <prestwoj@gmail.com>,
        linux-wireless@vger.kernel.org
Date:   Fri, 13 Sep 2019 23:01:29 +0200
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On Fri, 2019-09-13 at 13:56 -0700, James Prestwood wrote:
> Hi,
> 
> On Fri, 2019-09-13 at 22:48 +0200, Johannes Berg wrote:
> > On Fri, 2019-09-13 at 12:59 -0700, James Prestwood wrote:
> > > Add a new feature bit signifying that the wireless hardware
> > > supports
> > > changing the mac address while the underlying net_device is
> > > UP.  Note
> > > that this is slightly different from IFF_LIVE_ADDR_CHANGE as
> > > additional
> > > restrictions might be imposed by the hardware.  Typical
> > > restrictions
> > > are:
> > > 	- No connection is active on this interface, e.g. carrier is
> > > off
> > > 	- No scan is in progress
> > > 	- No offchannel operation is in progress
> > 
> > Hmm, what do you need this patch for?
> > 
> > IFF_LIVE_ADDR_CHANGE should be sufficient to discover it?
> 
> Because userspace needs to know if this is supported?
> IFF_LIVE_ADDR_CHANGE is a private flag... AFAIK userspace has no way of
> obtaining this.

Oh, annoying.

But that doesn't really mean that nl80211 is an appropriate place to
advertise it, IMHO?

And in nl80211 you'd need the flag for if you actually have the "change
MAC address during connect" attribute.

johannes