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Subject: Re: [PATCH 02/10] wl12xx: AP-mode - fix race condition on sta
 connection
From: Johannes Berg <johannes@sipsolutions.net>
To: Arik Nemtsov <arik@wizery.com>
Cc: linux-wireless@vger.kernel.org, Luciano Coelho <coelho@ti.com>
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Date: Wed, 26 Jan 2011 22:54:17 +0100
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On Wed, 2011-01-26 at 23:44 +0200, Arik Nemtsov wrote:

> Well no it doesn't do that. But the FW takes some time to know its
> authenticated.
> The flow is this:
> 
> 1. hostapd sends auth complete (the FW doesn't know anything about this)

you mean assoc, right?

> 2. The STA transmits something
> 3. The AP FW deauths the STA
> 4. hostapd adds the station, causing mac80211 to call add_sta(), which
> causes the FW to add the sta
> 
> Then we have an endless loop of sta add/remove..

I'd wondered about that race condition before -- maybe hostapd should
add the station before sending the assoc complete. The race also exists
in practice with just mac80211, except it only leads to a dropped frame.

johannes