Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751321AbdHXGAn (ORCPT ); Thu, 24 Aug 2017 02:00:43 -0400 Received: from paleale.coelho.fi ([176.9.41.70]:45468 "EHLO farmhouse.coelho.fi" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751283AbdHXGAl (ORCPT ); Thu, 24 Aug 2017 02:00:41 -0400 Message-ID: <1503554432.15969.415.camel@coelho.fi> From: Luca Coelho To: jikos@kernel.org, linux-wireless@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linuxwifi@intel.com, rui.zhang@intel.com, edubezval@gmail.com, linux-pm@vger.kernel.org, david.weinehall@intel.com, johannes.berg@intel.com, kvalo@codeaurora.org, sara.sharon@intel.com, emmanuel.grumbach@intel.com Date: Thu, 24 Aug 2017 09:00:32 +0300 In-Reply-To: <20170822073729.4856-1-luca@coelho.fi> References: <20170822073729.4856-1-luca@coelho.fi> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 91.156.4.241 X-SA-Exim-Mail-From: luca@coelho.fi Subject: Re: [PATCH v2] iwlwifi: pcie: move rx workqueue initialization to iwl_trans_pcie_alloc() X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: Yes (on farmhouse.coelho.fi) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1430 Lines: 33 On Tue, 2017-08-22 at 10:37 +0300, Luca Coelho wrote: > From: Luca Coelho > > Work queues cannot be allocated when a mutex is held because the mutex > may be in use and that would make it sleep. Doing so generates the > following splat with 4.13+: > > [ 19.513298] ====================================================== > [ 19.513429] WARNING: possible circular locking dependency detected > [ 19.513557] 4.13.0-rc5+ #6 Not tainted > [ 19.513638] ------------------------------------------------------ > [ 19.513767] cpuhp/0/12 is trying to acquire lock: > [ 19.513867] (&tz->lock){+.+.+.}, at: [] thermal_zone_get_temp+0x5b/0xb0 > [ 19.514047] > [ 19.514047] but task is already holding lock: > [ 19.514166] (cpuhp_state){+.+.+.}, at: [] cpuhp_thread_fun+0x3a/0x210 > [ 19.514338] > [ 19.514338] which lock already depends on the new lock. > > This lock dependency already existed with previous kernel versions, > but it was not detected until commit 49dfe2a67797 ("cpuhotplug: Link > lock stacks for hotplug callbacks") was introduced. > > Reported-by: David Weinehall > Reported-by: Jiri Kosina > Signed-off-by: Luca Coelho Jiri, did you have a chance to try this out? I'm about to ask Kalle to merge this so it gets in in time for 4.13-rc7. -- Cheers, Luca.