From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752346AbdJPMfw (ORCPT ); Mon, 16 Oct 2017 08:35:52 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:51188 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751410AbdJPMfu (ORCPT ); Mon, 16 Oct 2017 08:35:50 -0400 Date: Mon, 16 Oct 2017 14:34:48 +0200 (CEST) From: Thomas Gleixner To: Petri Latvala cc: Yu Chen , Juergen Gross , Boris Ostrovsky , Tony Luck , Marc Zyngier , Alok Kataria , Joerg Roedel , "Rafael J. Wysocki" , Steven Rostedt , Christoph Hellwig , Peter Zijlstra , Borislav Petkov , Paolo Bonzini , Rui Zhang , "K. Y. Srinivasan" , Arjan van de Ven , Dan Williams , Len Brown , LKML Subject: Re: Regression in linux-next In-Reply-To: Message-ID: References: <20171013110850.GA5303@yu-chen.sh.intel.com> <149ec6e8-4189-040c-a53c-12b0a51a855e@intel.com> User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: multipart/mixed; BOUNDARY="8323329-756566546-1508157288=:1973" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-756566546-1508157288=:1973 Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: 8BIT On Mon, 16 Oct 2017, Petri Latvala wrote: > > That should dump the trace buffer when the bug hits. I try to reproduce > > myself. > > With those: > > # rtcwake -s 15 -m mem > > [   67.069522] kernel BUG at arch/x86/kernel/apic/vector.c:154! > [   67.075509] invalid opcode: 0000 [#1] PREEMPT SMP > [   67.080481] Dumping ftrace buffer: Hrm. I completely forgot that this does not dump the buffers of offline CPUs. So half of the information is missing. So forget the tracer for now. Can you please apply the debug patch below and provide the full dmesg output? Its going to be too big for LKML so either upload it somewhere or send it to me in private mail. Note, I removed the BUG_ON, so box might survive suspend/resume but it should trigger that printout. Thanks, tglx 8<------------------------ --- a/arch/x86/kernel/apic/vector.c +++ b/arch/x86/kernel/apic/vector.c @@ -140,6 +140,10 @@ static void apic_update_vector(struct ir trace_vector_update(irqd->irq, newvec, newcpu, apicd->vector, apicd->cpu); + pr_err("VU: CPU %u irq %u newvec %u newcpu %u curvec %u curcpu %u desc %p\n", + smp_processor_id(),irqd->irq, newvec, newcpu, apicd->vector, + apicd->cpu, desc); + /* Setup the vector move, if required */ if (apicd->vector && cpu_online(apicd->cpu)) { apicd->move_in_progress = true; @@ -151,7 +155,9 @@ static void apic_update_vector(struct ir apicd->vector = newvec; apicd->cpu = newcpu; - BUG_ON(!IS_ERR_OR_NULL(per_cpu(vector_irq, newcpu)[newvec])); + if (!IS_ERR_OR_NULL(per_cpu(vector_irq, newcpu)[newvec])) + pr_err("VU not empty %p\n", per_cpu(vector_irq, newcpu)[newvec]); + per_cpu(vector_irq, newcpu)[newvec] = desc; } --8323329-756566546-1508157288=:1973--