Return-path: Received: from mail-bk0-f52.google.com ([209.85.214.52]:47946 "EHLO mail-bk0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932263AbaAaOTe convert rfc822-to-8bit (ORCPT ); Fri, 31 Jan 2014 09:19:34 -0500 Received: by mail-bk0-f52.google.com with SMTP id e11so2167888bkh.11 for ; Fri, 31 Jan 2014 06:19:33 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1391176316.4141.16.camel@jlt4.sipsolutions.net> References: <1391001747-9442-1-git-send-email-michal.kazior@tieto.com> <1391176316.4141.16.camel@jlt4.sipsolutions.net> Date: Fri, 31 Jan 2014 15:13:36 +0100 Message-ID: (sfid-20140131_151947_235894_CBC0D474) Subject: Re: [PATCH] cfg80211: consider existing DFS interfaces From: Michal Kazior To: Johannes Berg Cc: linux-wireless Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On 31 January 2014 14:51, Johannes Berg wrote: > On Wed, 2014-01-29 at 14:22 +0100, Michal Kazior wrote: >> It was possible to break interface combinations in >> the following way: >> >> combo 1: iftype = AP, num_ifaces = 2, num_chans = 2, >> combo 2: iftype = AP, num_ifaces = 1, num_chans = 1, radar = HT20 >> >> With the above interface combinations it was >> possible to: >> >> step 1. start AP on DFS channel by matching combo 2 >> step 2. start AP on non-DFS channel by matching combo 1 >> >> This was possible beacuse (step 2) did not consider >> if other interfaces require radar detection. >> >> The patch changes how cfg80211 tracks channels - >> instead of channel itself now a complete chandef >> is stored. > > Applied. > > Do you also want to take this a little further and actually check > compatibility when checking for channel availability in > cfg80211_can_use_iftype_chan()? Right now it only checks the channel, > but cfg80211_get_chan_state() should really not have a channel argument > but a chandef instead. I briefly looked at the issue and have seen challenges. Although I'm not actively implementing it I may end up doing it at some point. Michał