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Message-ID: <7f2722c9d30bb1a4715398b4f29309b1f383593b.camel@sipsolutions.net>
Subject: Re: [PATCH] mac80211: do not iterate active interfaces when in
 re-configure
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Ben Greear <greearb@candelatech.com>,
        linux-wireless@vger.kernel.org
Date:   Thu, 30 Jul 2020 15:13:42 +0200
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On Thu, 2020-07-30 at 06:05 -0700, Ben Greear wrote:

> > It might even be that this can only be done subject to driver choice.
> 
> I have tested this patch hard for many years with hundreds of station vifs on ath9k radios and
> 64 station vifs on ath10k radios, probably way harder than anyone else is testing
> this sort of thing.

Yeah, I'm sure!

> Possibly you are correct about iwlwifi, I've never tested it with multi-interface,
> and as you see, have had bad luck on ax200.

Right.

> If you'd accept a patch with a new driver flag check (which I can enable for
> ath10k and ath9k), then I'll respin it thus.

My order of preference would be something like

1. track per vif whether it was re-added, and skip before it is

If that works, I can certainly get behind it for semantic reasons (the
vif isn't yet active again), although even there I'm not sure how
iwlwifi would behave - but that's something I'd look into and perhaps
even consider a bug there since it shouldn't know about that interface
yet.

2. If for some reason that doesn't work, add an iteration flag that
controls this, rather than a per-device config?

johannes