From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752387AbbCUAjZ (ORCPT ); Fri, 20 Mar 2015 20:39:25 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:43550 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752060AbbCUAjY (ORCPT ); Fri, 20 Mar 2015 20:39:24 -0400 Message-ID: <550CBDB8.1090501@oracle.com> Date: Fri, 20 Mar 2015 18:39:20 -0600 From: David Ahern User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: David Rientjes CC: Linus Torvalds , linux-mm , LKML Subject: Re: 4.0.0-rc4: panic in free_block References: <550C37C9.2060200@oracle.com> <550CA3F9.9040201@oracle.com> <550CB8D1.9030608@oracle.com> In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/20/15 6:34 PM, David Rientjes wrote: > On Fri, 20 Mar 2015, David Ahern wrote: > >> Here's another data point: If I disable NUMA I don't see the problem. >> Performance drops, but no NULL pointer splats which would have been panics. >> >> The 128 cpu ldom with NUMA enabled shows the problem every single time I do a >> kernel compile (-j 128). With NUMA disabled I have done 3 allyesconfig >> compiles without hitting the problem. I'll put the compiles into a loop while >> I head out for dinner. >> > > It might be helpful to enable CONFIG_DEBUG_SLAB if you're reproducing it. > I enabled that and a few other DEBUG configs earlier -- nothing popped out. I'll do it again -- and others when I return.