From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753895AbdIDQyy convert rfc822-to-8bit (ORCPT ); Mon, 4 Sep 2017 12:54:54 -0400 Received: from mout.gmx.net ([212.227.15.19]:56690 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752687AbdIDQyx (ORCPT ); Mon, 4 Sep 2017 12:54:53 -0400 Message-ID: <1504544056.22981.13.camel@gmx.de> Subject: Re: hotplug lockdep splat (tip) From: Mike Galbraith To: Peter Zijlstra Cc: LKML , Thomas Gleixner , Byungchul Park Date: Mon, 04 Sep 2017 18:54:16 +0200 In-Reply-To: <1504542701.22981.3.camel@gmx.de> References: <1504350596.16793.44.camel@gmx.de> <1504421975.30792.32.camel@gmx.de> <20170904075502.74pgfd2twdfklspw@hirez.programming.kicks-ass.net> <1504531627.10288.5.camel@gmx.de> <20170904142419.6dfbwx5eedkykpeo@hirez.programming.kicks-ass.net> <1504542701.22981.3.camel@gmx.de> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.20.5 Mime-Version: 1.0 Content-Transfer-Encoding: 8BIT X-Provags-ID: V03:K0:1Pl1TALmR4Mw2btD5yGiCh+pv27gfisH+iXefmsOvHsBH6FxCbn JLtGUHEqREckVUAmjqnbo1TRwo/kmPxaIGnOH6JQ8XxxDAybFcgkzNL6Whc1w+IFacXTjOz lgmD5sXQ9ns7yws8esC4hR0haJXiNkjwHNfW9iQDCvHJC++Iyo32YUXEsAKQHkEJZ8rHrNU +Vi4/LzmYBiCFaINmSk5Q== X-UI-Out-Filterresults: notjunk:1;V01:K0:Ah/KjEB2W30=:ahIF56u86CuWzZZtxfcK5J ldqSeS9kWxFftuqNZ+A+j0C1nL0pADi/iHJg5fDNILqZ5q4lLy+Ro87ImOhxmFL7Gh/wxUCEE yoaY8ee3XOHVtExvN3yPGOi/zrwzw8QTkcK8qEvDBTehO04WquFS6X667bt/H2omD9RV/nhw0 zLyVbco4Qk0doB/BaX3RKvOffL/VkK81bYkdKK64P7Lnf2wjwm86C+zBVkeE5fewGeYRLzj9R VAVCXQe11Mrf37NStKKzkZ/hbWo1OAoksD7HSE8jVoZVe2Rrr45VhCL5Hffn1zJaVvWpOp96r UviYzoQg7ru3z/f6K6a3kAO6KzX8PxPc1GUZ0fU27fF97yisAfXZsyHh+E2wfg9faDirbAgsm MFXoJar7KvUHV3LzTHHpJ7FkI32frdHOlhXroE3egiUNXt/PIGicMO8oqJ8O8fRwfuwScZgII FQJxkcYCRmvdm+Z/vZwjQ6+5hsGcKDt6sBh3pnuFdd235OUrASJFSimHfhVYjkQhYFbNi+VaU dPvRRLnNraMdyReii21eGyemBEuI1kXitBGkajk53fnefOGNV71m9QR8FTHHaxUpVKXACf7eP fXMPRinh8FN2T1EnlbsOdn2UFs5Cm+hVNCQbjJBfNK+6RaWWU7eTR//SMazxQLfqVq9z7gTM2 EidQ8e9Fp6jEW+8HvU+y5cWCeJcV2CPVOg3uvG1ipdAagSVrNn9JIvN1Qh7QLdleFI3LkAfI1 5Wwlahw/8oyeh2cBlmI3R1c8IeEYUQNjO0aAqctV28LIn+XeeYWUvpgX59KAcSSEKe+Ac1t5P kJ+wkIxvZW1/pV/y/615YJXss3Xhp2FqTi0+spjW1xpuuuWA0E= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2017-09-04 at 18:31 +0200, Mike Galbraith wrote: > On Mon, 2017-09-04 at 16:24 +0200, Peter Zijlstra wrote: > > On Mon, Sep 04, 2017 at 03:27:07PM +0200, Mike Galbraith wrote: > > > On Mon, 2017-09-04 at 09:55 +0200, Peter Zijlstra wrote: > > > > On Sun, Sep 03, 2017 at 08:59:35AM +0200, Mike Galbraith wrote: > > > > > > > > > > [ 126.626908] Unregister pv shared memory for cpu 1 > > > > > [ 126.631041] > > > > > [ 126.631269] ====================================================== > > > > > [ 126.632442] WARNING: possible circular locking dependency detected > > > > > [ 126.633599] 4.13.0.g06260ca-tip-lockdep #2 Tainted: G E > > > > > [ 126.634380] ------------------------------------------------------ > > > > > [ 126.635124] stress-cpu-hotp/3156 is trying to acquire lock: > > > > > [ 126.635804] ((complete)&st->done){+.+.}, at: [] takedown_cpu+0x8a/0xf0 > > > > > [ 126.636809] > > > > > [ 126.636809] but task is already holding lock: > > > > > [ 126.637567] (sparse_irq_lock){+.+.}, at: [] irq_lock_sparse+0x17/0x20 > > > > > [ 126.638665] > > > > > > > > https://lkml.kernel.org/r/20170829193416.GC32112@worktop.programming.kicks-ass.net > > > > > > Well, flavor of gripe changed. > > > > > > [ 164.114290] ====================================================== > > > [ 164.115146] WARNING: possible circular locking dependency detected > > > [ 164.115751] 4.13.0.g90abd70-tip-lockdep #4 Tainted: G E > > > [ 164.116348] ------------------------------------------------------ > > > [ 164.116919] cpuhp/0/12 is trying to acquire lock: > > > [ 164.117381] (cpuhp_state){+.+.}, at: [] cpuhp_thread_fun+0x2a/0x160 > > > [ 164.118097] > > > but now in release context of a crosslock acquired at the following: > > > [ 164.118845] ((complete)&per_cpu_ptr(&cpuhp_state, i)->done#2){+.+.}, at: [] cpuhp_issue_call+0x13f/0x170 > > > [ 164.119789] > > > > Cute, I'd not seen that one.. anything special required to reproduce? > > No.  I build an enterprise(ish) config, run it in a KVM box, with the > guest being a full clone of the host, just memory constrained so it > can't oom the host. Qualifier: I run Steven's hotplug stress script, as that has killed oh so many kernels.. but I never run it alone.  In this case, I run stockfish with it, initial light survival test.  If I think things are looking pretty solid, I turn up the heat a bit, toss other things into the mix with random kill to make sure things don't get into a comfortable rut.   -Mike