Return-path: Received: from he.sipsolutions.net ([78.46.109.217]:37900 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752775Ab0FIHhA (ORCPT ); Wed, 9 Jun 2010 03:37:00 -0400 Subject: Re: [RFC 3/3] mac80211: Store basic rates for bss when joining ibss network From: Johannes Berg To: Teemu Paasikivi Cc: "linville@tuxdriver.com" , "linux-wireless@vger.kernel.org" In-Reply-To: <1276058714.495.35.camel@paavo-desktop> References: <1276000459-1121-1-git-send-email-ext-teemu.3.paasikivi@nokia.com> <1276000459-1121-2-git-send-email-ext-teemu.3.paasikivi@nokia.com> <1276000459-1121-3-git-send-email-ext-teemu.3.paasikivi@nokia.com> <1276000459-1121-4-git-send-email-ext-teemu.3.paasikivi@nokia.com> <1276001318.3706.130.camel@jlt3.sipsolutions.net> <1276058714.495.35.camel@paavo-desktop> Content-Type: text/plain; charset="UTF-8" Date: Wed, 09 Jun 2010 09:36:56 +0200 Message-ID: <1276069016.3727.3.camel@jlt3.sipsolutions.net> Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, 2010-06-09 at 07:45 +0300, Teemu Paasikivi wrote: > > However this kinda confuses me. > > > > We had a long-standing TODO item on our list at > > http://wireless.kernel.org/en/developers/todo-list > > > > "when leaving an IBSS and we were the only member, remove it from > > cfg80211's BSS list" > > > > Maybe that would help here too? > > > > Yes, I think that would propably solve that issue where IBSS was > recreated and requested basic rates are changed. Want to take a look at it? It shouldn't be too hard -- just call cfg80211_unlink_bss() somewhere where we still have the BSS pointer. Actually we don't keep it as you saw with the update, so need to find it first and then unlink it. > > However I don't understand the scenario anyway. If you create an IBSS, > > you start beaconing and tell cfg80211 about it with a frame that > > includes the supported and basic rates. Then you leave, but the BSS > > stays around in cfg80211 for 15 seconds. If you re-join within those 15 > > seconds, the scan results will pick up the old IBSS that no longer > > exists, and we "join" it rather than creating it. > > > > However -- joining it will take the basic rates from it. So wouldn't you > > get the old basic rates which is fine? What do you mean by "left unset"? > > > > By "left unset" I mean that in the sniffer logs there's no rates marked > as basic rates in the beacons. No old ones or new ones. Ok that's what I thought. But ... are they marked in our TX beacons when we _first_ created the IBSS? > > What happens if you join an IBSS that already exists? > > > > It works, but I haven't captured what's in the air. That's one reason > why I sent these patches as RFC. I don't really see how the two scenarios differ, so that's odd... johannes