From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753936AbbJPIJP (ORCPT ); Fri, 16 Oct 2015 04:09:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41619 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752762AbbJPIJE (ORCPT ); Fri, 16 Oct 2015 04:09:04 -0400 Date: Fri, 16 Oct 2015 10:08:58 +0200 From: Igor Mammedov To: Gonglei Cc: Christoph Lameter , "linux-kernel@vger.kernel.org" , "akpm@linux-foundation.org" , "vdavydov@parallels.com" , "rientjes@google.com" , Lizefan , "lqymgt@gmail.com" , "paulus@samba.org" , "tglx@linutronix.de" , "mingo@kernel.org" , "bp@suse.de" , "boris.ostrovsky@oracle.com" Subject: Re: [BUG?] kernel OOPS at kmem_cache_alloc_node() because of smp_processor_id() Message-ID: <20151016100858.68441f5c@nial.brq.redhat.com> In-Reply-To: <562073D0.8070609@huawei.com> References: <33183CC9F5247A488A2544077AF1902086F13201@SZXEMA503-MBS.china.huawei.com> <562073D0.8070609@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 16 Oct 2015 11:49:36 +0800 Gonglei wrote: > On 2015/10/15 22:39, Christoph Lameter wrote: > > On Thu, 15 Oct 2015, Gonglei (Arei) wrote: > > > >> [ 0.016000] Call Trace: > >> [ 0.016000] [] dump_trace+0x6c/0x2d0 > >> [ 0.016000] [] dump_stack+0x69/0x71 > >> [ 0.016000] [] panic+0x78/0x199 > >> [ 0.016000] [] do_exit+0x26f/0x360 > >> [ 0.016000] [] oops_end+0xe1/0xf0 > >> [ 0.016000] [] __bad_area_nosemaphore+0x155/0x230 > >> [ 0.016000] [] page_fault+0x1f/0x30 > >> [ 0.016000] [] kmem_cache_alloc_node+0xbf/0x140 > >> [ 0.016000] [] alloc_cpumask_var_node+0x16/0x70 > >> [ 0.016000] [] native_send_call_func_ipi+0x18/0xf0 > >> [ 0.016000] [] smp_call_function_many+0x1ae/0x250 > >> [ 0.016000] [] smp_call_function+0x20/0x30 > >> [ 0.016000] [] set_mtrr+0x5a/0x140 > >> [ 0.016000] [] smp_callin+0xf0/0x1b4 > >> [ 0.016000] [] start_secondary+0xe/0xb5 > > > > This happened during IPI processing? > > > >> crash> p cache_cache > > > > Arg. This is the SLAB allocator. You cannot enable debugging without > > rebuilding the kernel with CONFIG_SLAB_DEBUG. > > > >> smp_processor_id() return 14, the CPU14, but the CPU14 is *stuck*, so cache= > >> p->array[14] is NULL, > >> why did this situation happen? And cause NULL pointer accessing? Is this a = > >> kernel bug? > > > > Its likely a bug in some obscure code in a driver that corrupted memory or > > messed up the way memory was handled. set_mtrr()? What was going on at the > > time? A special graphics driver being loaded? That could cause issues. > > > > It seems that the problem was fixed by Igor, right? > https://lkml.org/lkml/2014/3/6/257 That might help. "stuck" CPU14 means that master CPU has given up on the attempt to online AP and tried to clean it up from different maps *but* AP is still running and that may lead to an unexpected behavior. > > Cced Igor Mammedov. > > Regards, > -Gonglei >