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Subject: Re: [PATCH 2/2] mac80211: Support LIVE_ADDRESS_CHANGE feature
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Denis Kenzior <denkenz@gmail.com>,
        James Prestwood <prestwoj@gmail.com>,
        linux-wireless@vger.kernel.org
Date:   Tue, 08 Oct 2019 19:08:28 +0200
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> > > > No, this typically cannot be fixed, and it doesn't really make sense.
> > > > The NIC cannot possibly do two scans at a time since it has only a
> > > > single radio resource :-)
> > > 
> > > So why is the scan request not per phy then?  And should mac address
> > > even affect the ongoing scan?  Can we simply change it with the scan
> > > ongoing?
> > 
> > There are things that affect the scan from the interface, e.g.
> > capability overrides, (extended) capabilities, the MAC address is used
> > unless randomization is requested, etc.
> > 
> 
> But they shouldn't change due a mac address change?  I wonder if we can 
> further relax the requirements to allow mac change if 
> NL80211_SCAN_FLAG_RANDOM_ADDR was used?

No, at least with HW scan that would completely confuse the driver -
since from the driver's POV we'd remove the interface it's currently
managing the scan for.

johannes