From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751312AbdBXJDF (ORCPT ); Fri, 24 Feb 2017 04:03:05 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:48365 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751125AbdBXJCx (ORCPT ); Fri, 24 Feb 2017 04:02:53 -0500 To: Peter Zijlstra , Matt Fleming , Thomas Gleixner , Linux Kernel Mailing List From: Christian Borntraeger Subject: v4.11-rc0: WARNING at kernel/sched/sched.h:812 set_next_entity on cpu hot(un)plug Date: Fri, 24 Feb 2017 10:01:51 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 17022409-0020-0000-0000-00000B7780E3 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00006673; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000204; SDB=6.00826372; UDB=6.00404726; IPR=6.00603824; BA=6.00005168; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00014422; XFM=3.00000011; UTC=2017-02-24 09:01:56 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17022409-0021-0000-0000-00005A6336EB Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-02-24_05:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1612050000 definitions=main-1702240090 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org While doing cpu hotunplug on s390 I got the following warning which indicates that Matts new check is either broken or finds real bugs. [ 190.608421] rq->clock_update_flags < RQCF_ACT_SKIP [ 190.608427] ------------[ cut here ]------------ [ 190.608434] WARNING: CPU: 29 PID: 153 at kernel/sched/sched.h:812 set_next_entity+0xc5e/0xc98 [ 190.608435] Kernel panic - not syncing: panic_on_warn set ... [ 190.608437] CPU: 29 PID: 153 Comm: migration/29 Not tainted 4.10.0+ #377 [ 190.608437] Hardware name: IBM 2964 NC9 704 (LPAR) [ 190.608438] Stack: [ 190.608438] 000000fb8ab875b8 000000fb8ab87648 0000000000000003 0000000000000000 [ 190.608439] 000000fb8ab876e8 000000fb8ab87660 000000fb8ab87660 0000000000000020 [ 190.608441] 000000000069dc1e 0000000000000020 000000000000000a 000000000000000a [ 190.608442] 000000000000000c 000000fb8ab876b0 0000000000000000 0000000000000000 [ 190.608443] 0000000000935d60 00000000001125ec 000000fb8ab87648 000000fb8ab876a0 [ 190.608444] Call Trace: [ 190.608448] ([<00000000001124a2>] show_trace+0x62/0x78) [ 190.608449] [<0000000000112590>] show_stack+0x68/0xe0 [ 190.608453] [<0000000000666c0e>] dump_stack+0x7e/0xb0 [ 190.608456] [<000000000027c704>] panic+0x104/0x240 [ 190.608457] [<0000000000140cd8>] cpuhp_invoke_callback+0x0/0x578 [ 190.608458] [<0000000000666376>] report_bug+0xce/0x150 [ 190.608459] [<0000000000100b10>] do_report_trap+0xf0/0x108 [ 190.608460] [<0000000000100c7e>] illegal_op+0xc6/0x160 [ 190.608464] [<000000000092bbfc>] pgm_check_handler+0x150/0x1a4 [ 190.608465] [<0000000000184906>] set_next_entity+0xc5e/0xc98 [ 190.608466] ([<0000000000184902>] set_next_entity+0xc5a/0xc98) [ 190.608467] [<000000000018a278>] pick_next_task_fair+0xa8/0x5b8 [ 190.608468] [<0000000000176ba8>] sched_cpu_dying+0x260/0x380 [ 190.608469] [<0000000000140d96>] cpuhp_invoke_callback+0xbe/0x578 [ 190.608470] [<0000000000141b70>] take_cpu_down+0x88/0xe0 [ 190.608472] [<00000000002015d6>] multi_cpu_stop+0x106/0x130 [ 190.608473] [<000000000020188c>] cpu_stopper_thread+0xf4/0x198 [ 190.608475] [<000000000016a754>] smpboot_thread_fn+0x134/0x1d0 [ 190.608478] [<00000000001658ea>] kthread+0x13a/0x158 [ 190.608479] [<000000000092baa6>] kernel_thread_starter+0x6/0xc [ 190.608480] [<000000000092baa0>] kernel_thread_starter+0x0/0xc Any immediate idea? Christian