Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752192Ab0BVJFB (ORCPT ); Mon, 22 Feb 2010 04:05:01 -0500 Received: from he.sipsolutions.net ([78.46.109.217]:56209 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751879Ab0BVJE7 (ORCPT ); Mon, 22 Feb 2010 04:04:59 -0500 Subject: Re: [2.6.33-rc5] Weird deadlock when shutting down From: Johannes Berg To: =?ISO-8859-1?Q?Am=E9rico?= Wang Cc: Xiaotian Feng , Linus Torvalds , Benjamin Herrenschmidt , "linux-kernel@vger.kernel.org" , Ingo Molnar , Peter Zijlstra In-Reply-To: <2375c9f91002220034m1beec51co7385a1cdbbcce7d2@mail.gmail.com> References: <1264740107.20211.53.camel@pasglop> <1266665331.12525.0.camel@jlt3.sipsolutions.net> <20100220134447.GA3000@hack> <1266674268.18465.6.camel@jlt3.sipsolutions.net> <2375c9f91002210151i6fe3f769k72a8a6a3485d8cf5@mail.gmail.com> <1266749023.5468.1.camel@jlt3.sipsolutions.net> <7b6bb4a51002210255t5ceaeb84r1438461085446385@mail.gmail.com> <7b6bb4a51002210312o2a1d070aneb54c107aeab6952@mail.gmail.com> <1266750881.10419.1.camel@jlt3.sipsolutions.net> <1266751349.10419.2.camel@jlt3.sipsolutions.net> <2375c9f91002220034m1beec51co7385a1cdbbcce7d2@mail.gmail.com> Content-Type: text/plain; charset="UTF-8" Date: Mon, 22 Feb 2010 10:04:50 +0100 Message-ID: <1266829490.5609.0.camel@jlt3.sipsolutions.net> Mime-Version: 1.0 X-Mailer: Evolution 2.29.3.2 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 987 Lines: 30 On Mon, 2010-02-22 at 16:34 +0800, Américo Wang wrote: > On Sun, Feb 21, 2010 at 7:22 PM, Johannes Berg > wrote: > > On Sun, 2010-02-21 at 12:14 +0100, Johannes Berg wrote: > > > >> printk("got cpu\n"); > >> for_each_online_cpu(i) { > >> sm_work = per_cpu_ptr(stop_machine_work, > i); > >> INIT_WORK(sm_work, stop_cpu); > >> queue_work_on(i, stop_machine_wq, sm_work); > >> } > >> /* This will release the thread on our CPU. */ > >> put_cpu(); > >> printk("put cpu\n"); > > > > As odd as that may be, it hangs in put_cpu() here. > > > > Hmm, does adding synchronize_sched() in _cpu_down() help? No luck. johannes -- 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/