Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752398AbZG1OlM (ORCPT ); Tue, 28 Jul 2009 10:41:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752063AbZG1OlM (ORCPT ); Tue, 28 Jul 2009 10:41:12 -0400 Received: from fias.uni-frankfurt.de ([141.2.248.1]:60092 "EHLO fias.uni-frankfurt.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752098AbZG1OlK (ORCPT ); Tue, 28 Jul 2009 10:41:10 -0400 From: Jan Scholz To: Johannes Berg Cc: Jan Scholz , "Rafael J. Wysocki" , Linux Kernel Mailing List , Kernel Testers List , Tomas Janousek , "John W. Linville" Subject: Re: [Bug #13337] [post 2.6.29 regression] hang during suspend of b44/b43 modules References: <87k52izvd9.fsf@scholz.fias.uni-frankfurt.de> <87y6qxx50z.fsf@scholz.fias.uni-frankfurt.de> <200907092203.10294.rjw@sisk.pl> <1247171295.1905.5.camel@johannes.local> <87prc78ga9.fsf@scholz.fias.uni-frankfurt.de> <1247322985.30647.108.camel@johannes.local> <8763dznnki.fsf@scholz.fias.uni-frankfurt.de> <1247334464.30647.109.camel@johannes.local> References: Date: Tue, 28 Jul 2009 16:40:36 +0200 In-Reply-To: <1247334464.30647.109.camel@johannes.local> (Johannes Berg's message of "Sat, 11 Jul 2009 19:47:44 +0200") Message-ID: <87my6ovpjv.fsf@scholz.fias.uni-frankfurt.de> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.0.96 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3048 Lines: 82 Johannes Berg writes: > On Sat, 2009-07-11 at 19:20 +0200, Jan Scholz wrote: >> Johannes Berg writes: >> >> > On Sat, 2009-07-11 at 16:07 +0200, Jan Scholz wrote: >> > >> >> > Jan, can you run with console_suspend=0 (or whatever it is now, Rafael >> >> > will correct me if I'm wrong) that should work on your platform, and put >> >> > a bunch of printk calls into __ieee80211_suspend in net/mac80211/pm.c to >> >> > see where in there it's hanging? >> >> >> >> Did that, seems like it hangs in >> >> drv_remove_interface(local, &conf); >> > >> > Ok, thanks! I was going to suggest doing the same in >> > b43_op_remove_interface in drivers/net/wireless/b43/main.c, but I think >> > the problem is just that we have an ordering problem and call drv_stop >> > before drv_remove_interface. I'll try to come up with a fix soon -- >> > might not be able to today though, in the meantime I guess you can just >> > move the drv_stop call to the end of the function and tell me if that >> > works -- that would be racy but should be ok most of the time. >> >> I moved drv_stop to the end of the function (see patch below) and now >> suspend works fine. > > Thanks, that's what I suspected -- I'll take a closer look into what is > required to make it race-free against RX. > Hi, The bug is still present in v2.6.31-rc4, it's still fixed by the patch (see below) suggested as a test by Johannes. Regards, Jan >> diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c >> index 7a549f9..0ac15fb 100644 >> --- a/net/mac80211/pm.c >> +++ b/net/mac80211/pm.c >> @@ -58,12 +58,6 @@ int __ieee80211_suspend(struct ieee80211_hw *hw) >> /* flush again, in case driver queued work */ >> flush_workqueue(local->hw.workqueue); >> >> - /* stop hardware - this must stop RX */ >> - if (local->open_count) { >> - ieee80211_led_radio(local, false); >> - drv_stop(local); >> - } >> - >> /* remove STAs */ >> spin_lock_irqsave(&local->sta_lock, flags); >> list_for_each_entry(sta, &local->sta_list, list) { >> @@ -111,6 +105,12 @@ int __ieee80211_suspend(struct ieee80211_hw *hw) >> drv_remove_interface(local, &conf); >> } >> >> + /* stop hardware - this must stop RX */ >> + if (local->open_count) { >> + ieee80211_led_radio(local, false); >> + drv_stop(local); >> + } >> + >> local->suspended = true; >> local->quiescing = false; >> -- Jan Scholz ____ ____ __ ___ ( ___)(_ _) /__\ / __) Frankfurt Institute for Advanced Studies )__) _)(_ /(__)\ \__ \ (__) (____)(__)(__)(___/ Goethe Universitaet Frankfurt Ruth-Moufang-Str. 1 Tel. 069-798-47534 60438 Frankfurt am Main -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/