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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 26882C2BCA1 for ; Fri, 7 Jun 2019 15:09:46 +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 7884321655 for ; Fri, 7 Jun 2019 15:09:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7884321655 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 45L5Y26MrZzDqFw for ; Sat, 8 Jun 2019 01:09:42 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0a-001b2d01.pphosted.com; envelope-from=nathanl@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 (mx0b-001b2d01.pphosted.com [148.163.158.5]) (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 45L5KV0zPSzDqS6 for ; Sat, 8 Jun 2019 00:59:41 +1000 (AEST) Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x57ErFET067069 for ; Fri, 7 Jun 2019 10:59:38 -0400 Received: from e33.co.us.ibm.com (e33.co.us.ibm.com [32.97.110.151]) by mx0b-001b2d01.pphosted.com with ESMTP id 2syqm18a49-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 07 Jun 2019 10:59:38 -0400 Received: from localhost by e33.co.us.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, 7 Jun 2019 15:59:35 +0100 Received: from b03ledav004.gho.boulder.ibm.com (b03ledav004.gho.boulder.ibm.com [9.17.130.235]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x57ExY6v20250956 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 7 Jun 2019 14:59:34 GMT Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 94A8C78060; Fri, 7 Jun 2019 14:59:34 +0000 (GMT) Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4606678063; Fri, 7 Jun 2019 14:59:34 +0000 (GMT) Received: from localhost (unknown [9.85.235.87]) by b03ledav004.gho.boulder.ibm.com (Postfix) with ESMTP; Fri, 7 Jun 2019 14:59:34 +0000 (GMT) From: Nathan Lynch To: Michael Ellerman , linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH] powerpc/pseries: fix oops in hotplug memory notifier In-Reply-To: <87tvd1h7bi.fsf@concordia.ellerman.id.au> References: <20190607050407.25444-1-nathanl@linux.ibm.com> <87tvd1h7bi.fsf@concordia.ellerman.id.au> Date: Fri, 07 Jun 2019 09:59:33 -0500 MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-GCONF: 00 x-cbid: 19060714-0036-0000-0000-00000AC83C2E X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00011228; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000286; SDB=6.01214571; UDB=6.00638460; IPR=6.00995656; MB=3.00027222; MTD=3.00000008; XFM=3.00000015; UTC=2019-06-07 14:59:36 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19060714-0037-0000-0000-00004C1FEED0 Message-Id: <878sudmofe.fsf@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-06-07_07:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1906070105 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: , Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Michael Ellerman writes: > Nathan Lynch writes: > >> During post-migration device tree updates, we can oops in >> pseries_update_drconf_memory if the source device tree has an >> ibm,dynamic-memory-v2 property and the destination has a >> ibm,dynamic_memory (v1) property. The notifier processes an "update" >> for the ibm,dynamic-memory property but it's really an add in this >> scenario. So make sure the old property object is there before >> dereferencing it. >> >> Signed-off-by: Nathan Lynch > > Can you pinpoint a commit that introduced the bug? Should we backport > this to stable? > > Perhaps? > Fixes: 2b31e3aec1db ("powerpc/drmem: Add support for ibm, dynamic-memory-v2 property") I guess I had considered it a latent bug, but you're right - we wouldn't hit it until the v2 support was added. So that commit is correct. Let me know if I should resend.