From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: net/bluetooth: workqueue destruction WARNING in hci_unregister_dev To: Tejun Heo References: <56C5CE85.6090808@suse.cz> <20160218174427.GG13177@mtj.duckdns.org> <56C6EC62.8080107@suse.cz> <56C70618.3010902@suse.cz> <20160302154507.GC4282@mtj.duckdns.org> Cc: Dmitry Vyukov , Marcel Holtmann , Gustavo Padovan , Johan Hedberg , "David S. Miller" , linux-bluetooth@vger.kernel.org, netdev , LKML , syzkaller , Kostya Serebryany , Alexander Potapenko , Sasha Levin , Eric Dumazet , Takashi Iwai From: Jiri Slaby Message-ID: <56D7FFE1.90900@suse.cz> Date: Thu, 3 Mar 2016 10:12:01 +0100 MIME-Version: 1.0 In-Reply-To: <20160302154507.GC4282@mtj.duckdns.org> Content-Type: text/plain; charset=windows-1252 List-ID: Hi, On 03/02/2016, 04:45 PM, Tejun Heo wrote: > On Fri, Feb 19, 2016 at 01:10:00PM +0100, Jiri Slaby wrote: >>> 1. didn't help, the problem persists. So I haven't applied the patch from 2. >> >> FWIW I dumped more info about the wq: >> wq->name='hci0' pwq=ffff8800390d7600 wq->dfl_pwq=ffff8800390d5200 >> pwq->refcnt=2 pwq->nr_active=0 delayed_works: > > Can you please print out the same info for all pwq's during shutdown? > It looks like we're leaking pwq refcnt but I can't spot a place where > that could happen on an empty pwq. I have not done that yet, but today, I see: destroy_workqueue: name='req_hci0' pwq=ffff88002f590300 wq->dfl_pwq=ffff88002f591e00 pwq->refcnt=2 pwq->nr_active=0 delayed_works: pwq 12: cpus=0-1 node=0 flags=0x4 nice=-20 active=0/1 in-flight: 18568:wq_barrier_func thanks, -- js suse labs From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Slaby Subject: Re: net/bluetooth: workqueue destruction WARNING in hci_unregister_dev Date: Thu, 3 Mar 2016 10:12:01 +0100 Message-ID: <56D7FFE1.90900@suse.cz> References: <56C5CE85.6090808@suse.cz> <20160218174427.GG13177@mtj.duckdns.org> <56C6EC62.8080107@suse.cz> <56C70618.3010902@suse.cz> <20160302154507.GC4282@mtj.duckdns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: Dmitry Vyukov , Marcel Holtmann , Gustavo Padovan , Johan Hedberg , "David S. Miller" , linux-bluetooth-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, netdev , LKML , syzkaller , Kostya Serebryany , Alexander Potapenko , Sasha Levin , Eric Dumazet , Takashi Iwai To: Tejun Heo Return-path: In-Reply-To: <20160302154507.GC4282-qYNAdHglDFBN0TnZuCh8vA@public.gmane.org> Sender: linux-bluetooth-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org Hi, On 03/02/2016, 04:45 PM, Tejun Heo wrote: > On Fri, Feb 19, 2016 at 01:10:00PM +0100, Jiri Slaby wrote: >>> 1. didn't help, the problem persists. So I haven't applied the patch from 2. >> >> FWIW I dumped more info about the wq: >> wq->name='hci0' pwq=ffff8800390d7600 wq->dfl_pwq=ffff8800390d5200 >> pwq->refcnt=2 pwq->nr_active=0 delayed_works: > > Can you please print out the same info for all pwq's during shutdown? > It looks like we're leaking pwq refcnt but I can't spot a place where > that could happen on an empty pwq. I have not done that yet, but today, I see: destroy_workqueue: name='req_hci0' pwq=ffff88002f590300 wq->dfl_pwq=ffff88002f591e00 pwq->refcnt=2 pwq->nr_active=0 delayed_works: pwq 12: cpus=0-1 node=0 flags=0x4 nice=-20 active=0/1 in-flight: 18568:wq_barrier_func thanks, -- js suse labs