Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752726AbaJVO2W (ORCPT ); Wed, 22 Oct 2014 10:28:22 -0400 Received: from mail-wi0-f174.google.com ([209.85.212.174]:33652 "EHLO mail-wi0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752592AbaJVO2T (ORCPT ); Wed, 22 Oct 2014 10:28:19 -0400 Message-ID: <5447BEFE.2040806@linaro.org> Date: Wed, 22 Oct 2014 16:28:14 +0200 From: Daniel Lezcano User-Agent: Mozilla/5.0 (X11; Linux i686; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: Jiri Kosina , Peter Zijlstra , Ingo Molnar , "Rafael J. Wysocki" , Pavel Machek , Steven Rostedt , Dave Jones , "Paul E. McKenney" , Nicolas Pitre CC: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Subject: Re: lockdep splat in CPU hotplug References: In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/22/2014 11:53 AM, Jiri Kosina wrote: > On Tue, 21 Oct 2014, Jiri Kosina wrote: > >> Hi, >> >> I am seeing the lockdep report below when resuming from suspend-to-disk >> with current Linus' tree (c2661b80609). >> >> The reason for CCing Ingo and Peter is that I can't make any sense of one >> of the stacktraces lockdep is providing. >> >> Please have a look at the very first stacktrace in the dump, where lockdep >> is trying to explain where cpu_hotplug.lock#2 has been acquired. It seems >> to imply that cpuidle_pause() is taking cpu_hotplug.lock, but that's not >> the case at all. >> >> What am I missing? > > Okay, reverting 442bf3aaf55a ("sched: Let the scheduler see CPU idle > states") and followup 83a0a96a5f26 ("sched/fair: Leverage the idle state > info when choosing the "idlest" cpu") which depends on it makes the splat > go away. Are you able to reproduce it by offlining the cpu and onlining it again ? -- Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog -- 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/