Date: Wed, 7 Dec 2011 21:23:27 +0530
From: Vasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
To: Johannes Berg <johannes@sipsolutions.net>
CC: <linville@tuxdriver.com>, <linux-wireless@vger.kernel.org>
Subject: Re: [PATCH] cfg80211: Fix race in bss timeout
Message-ID: <20111207155325.GC12498@chvasanth-lnx> (sfid-20111207_165353_871819_CC9FCF85)
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On Wed, Dec 07, 2011 at 04:37:28PM +0100, Johannes Berg wrote:
> > 
> > These warnings are added in cfg80211_roamed().
> 
> But this can be called directly by the driver with a NULL BSS.
> 
> Ohh. I see what you did, you didn't allow drivers calling this now. I
> think you should export this function still since otherwise the race
> windows might get tiny, but isn't actually completely closed (the first
> get_bss() might find it, the next a millisecond later not)

I can understand the millisecond delay between cfg80211_get_bss() in driver and
__cfg80211_roamed() as there can be delay in event_work getting
scheduled. I don't understand the delay between driver and
cfg80211_roamed() as the later one is direct call. Or this can be
done later if experienced the delay?.

Vasanth