From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED8B6C2BB1D for ; Fri, 17 Apr 2020 07:03:49 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6819B206B9 for ; Fri, 17 Apr 2020 07:03:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6819B206B9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 493Rry6QPHzDq9n for ; Fri, 17 Apr 2020 17:03:46 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=naveen.n.rao@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 493RpT1t7yzDrQn for ; Fri, 17 Apr 2020 17:01:36 +1000 (AEST) Received: from pps.filterd (m0187473.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 03H6h344055613 for ; Fri, 17 Apr 2020 03:01:33 -0400 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 30f7e4gcda-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 17 Apr 2020 03:01:33 -0400 Received: from localhost by e06smtp03.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 17 Apr 2020 08:01:07 +0100 Received: from d06av25.portsmouth.uk.ibm.com (d06av25.portsmouth.uk.ibm.com [9.149.105.61]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 03H71QiW53149902 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 17 Apr 2020 07:01:26 GMT Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0F69611C058; Fri, 17 Apr 2020 07:01:26 +0000 (GMT) Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 866AF11C050; Fri, 17 Apr 2020 07:01:25 +0000 (GMT) Received: from localhost (unknown [9.85.75.158]) by d06av25.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 17 Apr 2020 07:01:25 +0000 (GMT) Date: Fri, 17 Apr 2020 12:31:20 +0530 From: "Naveen N. Rao" Subject: Re: POWER9 crash due to STRICT_KERNEL_RWX (WAS: Re: Linux-next POWER9 NULL pointer NIP...) To: Qian Cai , Michael Ellerman , Russell Currey References: <15AC5B0E-A221-4B8C-9039-FA96B8EF7C88@lca.pw> <87eeszlb6u.fsf@mpe.ellerman.id.au> <0675B22E-8F32-432C-9378-FDE159DD1729@lca.pw> <20200407093054.3eb23e45@gandalf.local.home> <20200409101413.35d9c72d@gandalf.local.home> <06A2EA93-B730-4DB1-819F-D27E7032F0B3@lca.pw> <161662E3-5D9C-4C15-919C-CFEFE4CC35CB@lca.pw> <69F0448F-CA5B-497D-B8AF-2848175B9477@lca.pw> In-Reply-To: <69F0448F-CA5B-497D-B8AF-2848175B9477@lca.pw> MIME-Version: 1.0 User-Agent: astroid/v0.15-13-gb675b421 (https://github.com/astroidmail/astroid) Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 x-cbid: 20041707-0012-0000-0000-000003A603D0 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20041707-0013-0000-0000-000021E34692 Message-Id: <1587106774.1oa2whm69m.naveen@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.676 definitions=2020-04-17_01:2020-04-14, 2020-04-17 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 phishscore=0 adultscore=0 mlxscore=0 spamscore=0 lowpriorityscore=0 clxscore=1015 priorityscore=1501 suspectscore=2 bulkscore=0 mlxlogscore=932 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004170046 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Steven Rostedt , linuxppc-dev , LKML , Nicholas Piggin Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Hi Qian, Qian Cai wrote: > OK, reverted the commit, >=20 > c55d7b5e6426 (=E2=80=9Cpowerpc: Remove STRICT_KERNEL_RWX incompatibility = with RELOCATABLE=E2=80=9D) >=20 > or set STRICT_KERNEL_RWX=3Dn fixed the crash below and also mentioned in = this thread, >=20 > https://lore.kernel.org/lkml/15AC5B0E-A221-4B8C-9039-FA96B8EF7C88@lca.pw/ Do you see any errors logged in dmesg when you see the crash? =20 STRICT_KERNEL_RWX changes how patch_instruction() works, so it would be=20 interesting to see if there are any ftrace-related errors thrown before=20 the crash. - Naveen