Message-ID: <1390478869.4142.11.camel@jlt4.sipsolutions.net> (sfid-20140123_130756_073560_1F679707)
Subject: Re: [PATCH 5/7] mac80211: improve CSA locking
From: Johannes Berg <johannes@sipsolutions.net>
To: Luca Coelho <luca@coelho.fi>
Cc: Michal Kazior <michal.kazior@tieto.com>,
	linux-wireless <linux-wireless@vger.kernel.org>
Date: Thu, 23 Jan 2014 13:07:49 +0100
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On Thu, 2014-01-23 at 08:35 +0200, Luca Coelho wrote:

> > I was thinking about it. This should work, mostly, as long as you're
> > able to submit CSA requests fast enough and you don't use count 0 or
> > 1, in which case it becomes racy.
> 
> CSA with count 0 or 1 are really tricky in many respects.  But still I
> don't see why it would get racy.  The interfaces will switch
> independently, making their own chanctx reservations and so on...

You keep forgetting that Michał is mostly concerned with the non-chanctx
case, in which you can't switch them independently.

johannes