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Subject: Re: [PATCH] mac80211: Send deauth to STA's upon AP stop
To:     Johannes Berg <johannes@sipsolutions.net>,
        Shay Bar <Shay.Bar@celeno.com>
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From:   Ben Greear <greearb@candelatech.com>
Message-ID: <f0b038b4-fbd8-0b9b-2c2e-6337f0d408ea@candelatech.com>
Date:   Thu, 18 Jun 2020 08:26:51 -0700
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On 06/18/2020 07:48 AM, Johannes Berg wrote:
> On Thu, 2020-06-18 at 14:45 +0000, Shay Bar wrote:
>>> So... why would you ever do that? :)
>>> johannes
>>
>> :)
>> Is it illegal to do "ifconfig <if> down" or kill hostapd
>> while STA's are still associated?
>> There are some vendors/users that are doing that.
>
> It's not really *illegal* per se, but it would be weird if both did it
> ... But I do tend to think that if you're using hostapd or such to
> control it, you shouldn't do another out-of-band control.
>
>> Regarding Ben's proposal of using 11k/v, I couldn’t find such
>> "going down" single frame in the standard (although sounds trivial)
>
> Broadcast deauth :)

Or use k/v to tell STA that AP is going down immediately and here is (null, likely)
list of APs to associate with instead?

Another thing I notice:  In order to keep things from blocking for long periods (3+ seconds)
with rtnl held, I ended up doing a force flush in ath10k-ct, so at least when using that
driver, sending frames and then immediately doing flush will likely not put much on air.

I have hoped to one day add tx-completion call-backs handling to mac80211 instead of just calling a flush
for these types of station-down communication where flush is to be called shortly.

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com