Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752450Ab0BVJO1 (ORCPT ); Mon, 22 Feb 2010 04:14:27 -0500 Received: from he.sipsolutions.net ([78.46.109.217]:50854 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752110Ab0BVJO0 (ORCPT ); Mon, 22 Feb 2010 04:14:26 -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: <2375c9f91002220112q351044a4ycf4ee7dc2630c16d@mail.gmail.com> References: <1264740107.20211.53.camel@pasglop> <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> <1266829490.5609.0.camel@jlt3.sipsolutions.net> <2375c9f91002220112q351044a4ycf4ee7dc2630c16d@mail.gmail.com> Content-Type: text/plain; charset="UTF-8" Date: Mon, 22 Feb 2010 10:14:11 +0100 Message-ID: <1266830051.5609.6.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: 789 Lines: 22 On Mon, 2010-02-22 at 17:12 +0800, Américo Wang wrote: > Since it hangs in put_cpu() which is just preempt_enable(), so I began > to suspect if we need a synchronize_sched(), or some barrier perhaps. > I am not sure at all. Right. > Before other experts look at this, I think doing a bisect would be > very useful. I was afraid you'd say that, it'll take forever though since I need to walk over to it after every shutdown, see if it turned off and then turn it on again (and possibly off).... I guess I'll get started on that. 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/