Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755292AbcLZPpJ (ORCPT ); Mon, 26 Dec 2016 10:45:09 -0500 Received: from ud10.udmedia.de ([194.117.254.50]:54354 "EHLO mail.ud10.udmedia.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752994AbcLZPpH (ORCPT ); Mon, 26 Dec 2016 10:45:07 -0500 Date: Mon, 26 Dec 2016 16:45:02 +0100 From: Markus Trippelsdorf To: Thomas Gleixner Cc: Linus Torvalds , LKML , Ingo Molnar , "H. Peter Anvin" , Sebastian Andrzej Siewior , Borislav Petkov Subject: Re: [GIT pull] smp/hotplug: Removal of notifiers Message-ID: <20161226154502.GA287@x4> References: <20161226074530.GA297@x4> <20161226110600.GB297@x4> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161226110600.GB297@x4> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1825 Lines: 53 On 2016.12.26 at 12:06 +0100, Markus Trippelsdorf wrote: > On 2016.12.26 at 08:45 +0100, Markus Trippelsdorf wrote: > > On 2016.12.25 at 14:39 +0100, Thomas Gleixner wrote: > > > Linus, > > > > > > please pull the latest smp-urgent-for-linus git tree from: > > > > > > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git smp-urgent-for-linus > > > > > > Thomas Gleixner (11): > > > cpu/hotplug: Prevent overwriting of callbacks > > > > The following commit: > > > > commit dc280d93623927570da279e99393879dbbab39e7 > > Author: Thomas Gleixner > > Date: Wed Dec 21 20:19:49 2016 +0100 > > > > cpu/hotplug: Prevent overwriting of callbacks > > > > results in an early OOPs during boot on my AMD machine. > > I haven't wrote down the entire backtrace, but basically things start to > > go wrong in mce_threshold_create_device() from > > arch/x86/kernel/cpu/mcheck/mce_amd.c. > > > > # CONFIG_HOTPLUG_CPU is not set > > > > Reverting the commit "fixes" the issue for me. > > CCing Sebastian and Borislav. BUG: unable to handle kernel NULL pointer dereference at 000000000000004c RIP: kobject_get at lib/kobject.c:594 (inlined by) kobject_add_internal at lib/kobject.c:214 ? kobj_to_dev at include/linux/device.h:968 (discriminator 1) (inlined by) get_device at drivers/base/core.c:1796 (discriminator 1) ? kobject_add at lib/kobject.c:415 ? kobject_create_and_add at lib/kobject.c:753 ? threshold_create_bank at arch/x86/kernel/cpu/mcheck/mce_amd.c:1212 (inlined by) mce_threshold_create_device at arch/x86/kernel/cpu/mcheck/mce_amd.c:1348 The comment in arch/x86/kernel/cpu/mcheck/mce_amd.c says: 1384 * mcheck_init_device should be inited before threshold_init_device to 1385 * initialize mce_device, otherwise a NULL ptr dereference will cause panic. -- Markus