From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail.candelatech.com ([208.74.158.172]:46772 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751934Ab0KPQvx (ORCPT ); Tue, 16 Nov 2010 11:51:53 -0500 Message-ID: <4CE2B6A0.8020709@candelatech.com> Date: Tue, 16 Nov 2010 08:51:44 -0800 From: Ben Greear MIME-Version: 1.0 To: Tejun Heo CC: Johannes Berg , linux-wireless@vger.kernel.org Subject: Re: [PATCH] mac80211: Fix deadlock in ieee80211_do_stop. References: <1289592426-5367-1-git-send-email-greearb@candelatech.com> <1289594998.3736.11.camel@jlt3.sipsolutions.net> <4CDDAA3B.9090007@candelatech.com> <1289596096.3736.13.camel@jlt3.sipsolutions.net> <4CDE699B.70401@kernel.org> <4CE1A344.7040201@candelatech.com> <4CE292F7.4090200@kernel.org> In-Reply-To: <4CE292F7.4090200@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 11/16/2010 06:19 AM, Tejun Heo wrote: > Hello, > > On 11/15/2010 10:16 PM, Ben Greear wrote: >> Here's the full trace of sysrq-t output: > > Hmmm... for some reason, the dump is not complete. Only two kworkers > are printed out. > Can you please do the followings? > > 1. Try to capture the full dump. Usually serial console works best. This was from serial console, and I grabbed everything it printed to the screen. I'll look in /var/log/messages in case there is more there. If you have a system with an ath5k nic, I should be able to show you how to reproduce it, if you're interested. > 2. Does adding WQ_MEM_RECLAIM to alloc_ordered_workqueue() call in > ieee80211_register_hw() make any difference? > > 3. What if you replace it with the following? > > alloc_workqueue(wiphy_name(local->hw.wiphy), WQ_NON_REENTRANT, 0) I can try these things..hopefully today. Can you explain briefly how this is supposed to work? I'm certain that some workers can be blocked attempting to get rtnl. When we call flush_work(), how is a worker chosen/created to flush that work? Thanks, Ben > > Thanks. > -- Ben Greear Candela Technologies Inc http://www.candelatech.com