From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753186Ab0H2L46 (ORCPT ); Sun, 29 Aug 2010 07:56:58 -0400 Received: from mx3-phx2.redhat.com ([209.132.183.24]:36697 "EHLO mx01.colomx.prod.int.phx2.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752907Ab0H2L45 (ORCPT ); Sun, 29 Aug 2010 07:56:57 -0400 Date: Sun, 29 Aug 2010 07:56:45 -0400 (EDT) From: CAI Qian To: Tejun Heo Cc: torvalds@linux-foundation.org, linux-next@vger.kernel.org, kexec , linux-kernel Message-ID: <1236896997.1479691283083005518.JavaMail.root@zmail06.collab.prod.int.phx2.redhat.com> In-Reply-To: <171172387.1479581283082093912.JavaMail.root@zmail06.collab.prod.int.phx2.redhat.com> Subject: Re: kdump regression compared to v2.6.35 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [10.5.5.71] X-Mailer: Zimbra 5.0.21_GA_3150.RHEL4_64 (ZimbraWebClient - FF3.0 (Linux)/5.0.21_GA_3150.RHEL4_64) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ----- caiqian@redhat.com wrote: > ----- "Tejun Heo" wrote: > > > Hello, > > > > On 08/29/2010 01:24 PM, CAI Qian wrote: > > >> On 08/29/2010 09:01 AM, caiqian@redhat.com wrote: > > >>> Further bisect indicated this bad commit from the merge. Given > kdump > > >>> kernel was running with maxcpus=1, I guess this work caused > > fs/bio.c > > >>> hung in the workqueue on UP. Reverted the whole merge let kdump > > work > > >>> again. > > >> > > >> Can you please pull from the following git tree and see whether > it > > >> fixes the problem? There was a bug in nr_active accounting. > > > > > > It had the same problem. > > > > I see. Hmm... a different issue then. Can you please tell me how > to > > reproduce the problem? It is easy to reproduce by passing maxcpus=1 to the first kernel. > First, to configure kdump - see Documentation/kdump/kdump.txt. It > might be easier if you are using a distro that provide advanced kdump > tools. Then, to trigger the kdump - echo c >/proc/sysrq-trigger. In > case needed, here is the system information, > # lscpu > Architecture: x86_64 > CPU op-mode(s): 32-bit, 64-bit > CPU(s): 64 > Thread(s) per core: 2 > Core(s) per socket: 8 > CPU socket(s): 4 > NUMA node(s): 4 > Vendor ID: GenuineIntel > CPU family: 6 > Model: 46 > Stepping: 6 > CPU MHz: 1064.000 > Virtualization: VT-x > L1d cache: 32K > L1i cache: 32K > L2 cache: 256K > L3 cache: 18432K > NUMA node0 CPU(s): 0,4,8,12,16,20,24,28,32,36,40,44,48,52,56,60 > NUMA node1 CPU(s): 1,5,9,13,17,21,25,29,33,37,41,45,49,53,57,61 > NUMA node2 CPU(s): 2,6,10,14,18,22,26,30,34,38,42,46,50,54,58,62 > NUMA node3 CPU(s): 3,7,11,15,19,23,27,31,35,39,43,47,51,55,59,63 > > > Thanks. > > > > -- > > tejun > > > > _______________________________________________ > > kexec mailing list > > kexec@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/kexec