From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757029Ab2JWNJw (ORCPT ); Tue, 23 Oct 2012 09:09:52 -0400 Received: from mail-bk0-f46.google.com ([209.85.214.46]:55773 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756567Ab2JWNJu (ORCPT ); Tue, 23 Oct 2012 09:09:50 -0400 Message-ID: <5086971A.1070009@linaro.org> Date: Tue, 23 Oct 2012 15:09:46 +0200 From: Daniel Lezcano User-Agent: Mozilla/5.0 (X11; Linux i686; rv:12.0) Gecko/20120430 Thunderbird/12.0.1 MIME-Version: 1.0 To: Fengguang Wu CC: "Rafael J. Wysocki" , LKML Subject: Re: [CPU hotplug, cpuidle_disable_device] BUG: unable to handle kernel NULL pointer dereference at (null) References: <20121023124856.GA17692@localhost> In-Reply-To: <20121023124856.GA17692@localhost> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/23/2012 02:48 PM, Fengguang Wu wrote: Hi Fengguang, I believe this bug has been fixed by https://lkml.org/lkml/2012/10/8/87 Thanks for reporting the problem. -- Daniel > Hi Daniel, > > When doing CPU hotplug tests, I got the following bug > > [ 25.979429] KVM setup async PF for cpu 1 > [ 25.980593] kvm-stealtime: cpu 1, msr 1f40d140 > [ 25.982728] BUG: unable to handle kernel NULL pointer dereference at (null) > [ 25.982741] IP: [] cpuidle_disable_device+0xc/0x5c > [ 25.982744] PGD 1adb6067 PUD 18d97067 PMD 0 > [ 25.982747] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC > [ 25.982749] Modules linked in: > [ 25.982753] CPU 0 > [ 25.982753] Pid: 2273, comm: 01-cpu-hotplug Not tainted 3.6.0-00324-g8937cc5 #1290 Bochs Bochs > [ 25.982756] RIP: 0010:[] [] cpuidle_disable_device+0xc/0x5c > [ 25.982760] RSP: 0018:ffff880018c75cd8 EFLAGS: 00010246 > [ 25.982761] RAX: ffff880018c75fd8 RBX: ffff88001b49c000 RCX: ffff880018c3aaf0 > [ 25.982762] RDX: 0000000000000006 RSI: ffff880018c3aaf0 RDI: 0000000000000000 > [ 25.982764] RBP: ffff880018c75ce8 R08: ffff880018c75c88 R09: 000000000000000a > [ 25.982765] R10: ffff88001f20a000 R11: ffff880018c3aaf0 R12: 0000000000000000 > [ 25.982766] R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff81ce2a70 > [ 25.982767] FS: 00007f286a3fc700(0000) GS:ffff88001f200000(0000) knlGS:0000000000000000 > [ 25.982769] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b > [ 25.982770] CR2: 0000000000000000 CR3: 0000000018c7c000 CR4: 00000000000006f0 > [ 25.982774] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > [ 25.982778] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > [ 25.982779] Process 01-cpu-hotplug (pid: 2273, threadinfo ffff880018c74000, task ffff880018c3a350) > [ 25.982780] Stack: > [ 25.982782] ffff88001b49c000 0000000000000000 ffff880018c75d18 ffffffff8137732f > [ 25.982785] ffff88001b49c000 ffff88001b49c000 0000000000000002 ffffffff81c81c01 > [ 25.982787] ffff880018c75d48 ffffffff81374dd7 0000000000000001 0000000000000001 > [ 25.982788] Call Trace: > [ 25.982799] [] acpi_processor_hotplug+0x55/0x97 > [ 25.982801] [] acpi_cpu_soft_notify+0x92/0xcd > [ 25.982804] [] notifier_call_chain+0x65/0x95 > [ 25.982812] [] __raw_notifier_call_chain+0xe/0x10 > [ 25.982816] [] __cpu_notify+0x20/0x37 > [ 25.982819] [] cpu_notify+0x13/0x15 > [ 25.982834] [] _cpu_up+0x16c/0x1ae > [ 25.982837] [] cpu_up+0x6f/0x81 > [ 25.982839] [] store_online+0x5f/0x8f > [ 25.982847] [] dev_attr_store+0x18/0x24 > [ 25.982857] [] sysfs_write_file+0xee/0x126 > [ 25.982865] [] vfs_write+0xa6/0x132 > [ 25.982868] [] sys_write+0x4c/0x80 > [ 25.982871] [] tracesys+0xd0/0xd5 > [ 25.982898] Code: d8 48 01 d6 48 81 fe ff ff ff 7f 48 0f 4e ce 41 89 4c 24 08 48 83 c4 28 5b 41 5c 41 5d 5d c3 0f 1f 44 00 00 55 48 89 e5 41 54 53 07 02 48 89 fb 74 43 e8 e2 05 00 00 48 85 c0 74 39 48 83 3d > [ 25.982900] RIP [] cpuidle_disable_device+0xc/0x5c > [ 25.982901] RSP > [ 25.982902] CR2: 0000000000000000 > > which is bisected to: > > 3d339dcbb56d8d70c1b959aff87d74adc3a84eea is the first bad commit > commit 3d339dcbb56d8d70c1b959aff87d74adc3a84eea > Author: Daniel Lezcano > Date: Mon Sep 17 23:01:56 2012 +0200 > > cpuidle / ACPI : move cpuidle_device field out of the acpi_processor_power structure > > Thanks, > Fengguang -- Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog