From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935118AbYEUNDf (ORCPT ); Wed, 21 May 2008 09:03:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757980AbYEUND1 (ORCPT ); Wed, 21 May 2008 09:03:27 -0400 Received: from bzq-179-150-194.static.bezeqint.net ([212.179.150.194]:25966 "EHLO il.qumranet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756675AbYEUND0 (ORCPT ); Wed, 21 May 2008 09:03:26 -0400 Message-ID: <48341D9C.7010700@qumranet.com> Date: Wed, 21 May 2008 16:03:24 +0300 From: Avi Kivity User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: Heiko Carstens CC: Dmitry Adamushko , linux-kernel , Ingo Molnar , Peter Zijlstra , Srivatsa Vaddagiri Subject: Re: [BUG] cpu hotplug vs scheduler References: <4829A6A0.5040208@qumranet.com> <482ADB69.8010305@qumranet.com> <482C0E35.9000708@qumranet.com> <20080521123116.GC9441@osiris.boeblingen.de.ibm.com> <483418CB.7070602@qumranet.com> <20080521125546.GE9441@osiris.boeblingen.de.ibm.com> In-Reply-To: <20080521125546.GE9441@osiris.boeblingen.de.ibm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Heiko Carstens wrote: > On Wed, May 21, 2008 at 03:42:51PM +0300, Avi Kivity wrote: > >> Heiko Carstens wrote: >> >>> I think you fixed this specific bug. Does cpu hotplug stresstest now work >>> for you? >>> >> Which bug, the order-2 allocs? I certainly didn't fix it. >> >> Last I tried, cpu hotplug still failed, but it was some time ago as >> patches flow. >> > > Ah no. I thought "x86: fix crash on cpu hotplug on pat-incapable machines" > would have fixed the cpu hotplug bug for you. > > No, that only fixes an immediate oops when running in a virtual machine (which doesn't have pat). > I was actually talking of the pick_next_task_fair incarnation of one of > the cpu hotplug bugs. > > That hasn't been addressed, AFAIK. > s390 backtrace on 2.6.25 looks like this. > > <1>Unable to handle kernel pointer dereference at virtual kernel address 00000200000db000 > <4>Oops: 003b [#1] PREEMPT SMP > <4>Modules linked in: dm_multipath sunrpc qeth_l2 dm_mod cu3088 qeth ccwgroup > <4>CPU: 0 Not tainted 2.6.25-27.x.20080422-s390xdefault #1 > <4>Process migration/0 (pid: 5806, task: 00000000aac3a838, ksp: 000000017a2f3dd0) > <4>Krnl PSW : 0400200180000000 0000000000125f48 (pick_next_task_fair+0x34/0xd4) > <4> R:0 T:1 IO:0 EX:0 Key:0 M:0 W:0 P:0 AS:0 CC:2 PM:0 EA:3 > <4>Krnl GPRS: 0000079e029c6ecb 0000000000000000 000000008548ea60 000000008548d700 > <4> 00000000004526f8 0000000000000597 0000000000000000 0000000000000000 > <4> 0000000000672a00 0000000000000000 00000000aac3a838 000000017a2f3d10 > <4> 00000200000db85a 00000000004672a0 000000017a2f3d50 000000017a2f3d10 > <4>Krnl Code: 0000000000125f38: e3e0f0980024 stg %r14,152(%r15) > <4> 0000000000125f3e: d507d000c010 clc 0(8,%r13),16(%r12) > <4> 0000000000125f44: a784004e brc 8,125fe0 > <4> >0000000000125f48: d507d000c030 clc 0(8,%r13),48(%r12) > <4> 0000000000125f4e: b904002c lgr %r2,%r12 > <4> 0000000000125f52: a7990000 lghi %r9,0 > <4> 0000000000125f56: a7840033 brc 8,125fbc > <4> 0000000000125f5a: c0e5ffffee23 brasl %r14,123ba0 > <4>Call Trace: > <4>([<00000000aac3a838>] 0xaac3a838) > <4> [<000000000045270c>] schedule+0x178/0x978 > <4> [<000000000012fe86>] migration_thread+0x1aa/0x30c > <4> [<0000000000152ad8>] kthread+0x68/0xa0 > <4> [<000000000010a0be>] kernel_thread_starter+0x6/0xc > <4> [<000000000010a0b8>] kernel_thread_starter+0x0/0xc > <4>Last Breaking-Event-Address: > <4> [<0000000000125fc6>] pick_next_task_fair+0xb2/0xd4 > Seems to be the same bug, yes. -- error compiling committee.c: too many arguments to function