Return-path: Received: from mail-lb0-f181.google.com ([209.85.217.181]:37419 "EHLO mail-lb0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750732AbaCPEnG (ORCPT ); Sun, 16 Mar 2014 00:43:06 -0400 Received: by mail-lb0-f181.google.com with SMTP id c11so2757462lbj.26 for ; Sat, 15 Mar 2014 21:43:04 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <1393376982-28276-1-git-send-email-mcgrof@do-not-panic.com> <1393376982-28276-3-git-send-email-mcgrof@do-not-panic.com> <1393852248.10039.5.camel@jlt4.sipsolutions.net> From: "Luis R. Rodriguez" Date: Sat, 15 Mar 2014 21:42:43 -0700 Message-ID: (sfid-20140316_054335_689754_8978DBFD) Subject: Re: [PATCH 2/3] cfg80211: fix processing world regdomain when non modular To: Janusz Dziedzic Cc: Colleen T , Johannes Berg , linux-wireless , Sander Eikelenboom Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Sat, Mar 15, 2014 at 8:59 AM, Janusz Dziedzic wrote: > 2014-03-15 2:03 GMT+01:00 Luis R. Rodriguez : >> On Fri, Mar 14, 2014 at 3:12 PM, Colleen T wrote: >>> I'm on mac80211-next/master, sha is >>> 5a970df8990d173e7e4092952f2e3da1de69b27d >> >> I tried to reproduce by just merging the fixes in question onto Linus' >> tree and using radios=3 but no go. Can you provide the full kernel >> log, I'm particularly interested in what happened before. The >> COUNTRY=US on debian, which I believe you're on, should just trigger a >> regulatory domain setting to US upon initialization. Depending on how >> Debian does it this could either trigger as a module parameter or as a >> userspace event *after* the world regdom get set. >> >> The radios=3 alone would not do anything other than add new radios so >> I see no contention on the last_request by increasing or decreasing >> that. last_request is also protected by rtnl and although I was >> considering a possible race against processing the same last_request >> twice if you see how we call reg_process_pending_hints() on reg_todo() >> its protected by rtnl_lock() so I'm a bit puzzled as to how this is >> being triggered as those operations should be atomic. The other corner >> case I thought of was that for userspace requests which sets a >> timeout, but our when the timeout hits we also rtnl_lock() under >> reg_timeout_work(). >> >> The other corner I thought of was when we reset_regdomains() but all >> callers are rtnl_lock()'d. This is also the same for callers of >> set_regdom(). >> >> Do you get different results if you reduce the number of radios? If so >> where's the trigger point? >> > > Just guessing, try add this one if not included in mac80211-next yet. > > [PATCH 1/2] cfg80211: regulatory, reset regdomain in case of error - > this goes to 3.14 directly. Thanks for poingint that out Janusz, that patch is not in mac80211-next. Colleen it'd be curious if that fixes your issue but I don't see how given that I don't see how your situation would hit the error case. It is certainly worth trying. In any case please do provide the full kernel log and please try the other things I mentioned, the more detail the better. Luis