Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753459AbXLJJMJ (ORCPT ); Mon, 10 Dec 2007 04:12:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751036AbXLJJL4 (ORCPT ); Mon, 10 Dec 2007 04:11:56 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:36219 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750941AbXLJJL4 (ORCPT ); Mon, 10 Dec 2007 04:11:56 -0500 Date: Mon, 10 Dec 2007 10:10:52 +0100 From: Ingo Molnar To: Jiri Slaby Cc: ego@in.ibm.com, Andrew Morton , linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , Arjan van de Ven , Thomas Gleixner , Linux-pm mailing list , Dipankar Sarma Subject: Re: broken suspend (sched related) [Was: 2.6.24-rc4-mm1] Message-ID: <20071210091052.GA14487@elte.hu> References: <20071207151150.GB24254@elte.hu> <20071207175134.GA18916@elte.hu> <475A5188.6070809@gmail.com> <20071208083939.GD30997@elte.hu> <475A629C.7010408@gmail.com> <20071208152447.GA30270@elte.hu> <475B24F4.3090904@gmail.com> <20071209074647.GE22981@elte.hu> <20071210081952.GA7215@in.ibm.com> <475CFF01.2090502@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <475CFF01.2090502@gmail.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 759 Lines: 19 > > softlockup: remove get_online_cpus() which doesn't help here. > > > > The get_online_cpus() protection seems to be bogus in > > kernel/softlockup.c as cpu cached in check_cpu can go offline once > > we do a put_online_cpus(). > > > > This can also cause deadlock during a cpu offline as follows: i'm wondering, what's the proper CPU-hotplug safe sequence here then? I'm picking a CPU number from cpu_online_map, and that CPU could go away while i'm still using it, right? What's saving us here? Ingo -- 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/