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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,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 57156C432C0 for ; Thu, 21 Nov 2019 20:56:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 04C3520672 for ; Thu, 21 Nov 2019 20:56:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="DfvuvHfE"; dkim=pass (1024-bit key) header.d=fb.onmicrosoft.com header.i=@fb.onmicrosoft.com header.b="Fr3iYi9A" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 04C3520672 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=fb.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A78CF6B0384; Thu, 21 Nov 2019 15:56:47 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A2B266B0385; Thu, 21 Nov 2019 15:56:47 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8F27F6B0386; Thu, 21 Nov 2019 15:56:47 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0089.hostedemail.com [216.40.44.89]) by kanga.kvack.org (Postfix) with ESMTP id 7780C6B0384 for ; Thu, 21 Nov 2019 15:56:47 -0500 (EST) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id 2F395181AEF1E for ; Thu, 21 Nov 2019 20:56:47 +0000 (UTC) X-FDA: 76181493654.08.love62_7563464e5c33f X-HE-Tag: love62_7563464e5c33f X-Filterd-Recvd-Size: 9562 Received: from mx0b-00082601.pphosted.com (mx0b-00082601.pphosted.com [67.231.153.30]) by imf08.hostedemail.com (Postfix) with ESMTP for ; Thu, 21 Nov 2019 20:56:46 +0000 (UTC) Received: from pps.filterd (m0109331.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id xALKubIG005449; Thu, 21 Nov 2019 12:56:41 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : references : in-reply-to : content-type : content-id : content-transfer-encoding : mime-version; s=facebook; bh=2OCbpaHS6orm4nl7xo5ZqCbhiUNlOOgT+wxlBshbgc8=; b=DfvuvHfEwhT+UfAu/B9RnwIEJ38UU0k7+Jf13gat06t+SCEIRzViU/XoVUjuJPOUZ7wD 30at9Z5FAQfLToUrdnKAW7OXjSpRfIjCDUagIUK2gyAu/H8tjEiELfsvDcjG/jNwQT5B JcXz7/36jt0XiNnhK3EnECBpxe24X14AaDM= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 2wddynsmdx-4 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Thu, 21 Nov 2019 12:56:41 -0800 Received: from ash-exhub204.TheFacebook.com (2620:10d:c0a8:83::4) by ash-exhub201.TheFacebook.com (2620:10d:c0a8:83::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Thu, 21 Nov 2019 12:55:29 -0800 Received: from NAM03-CO1-obe.outbound.protection.outlook.com (100.104.31.183) by o365-in.thefacebook.com (100.104.36.100) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5 via Frontend Transport; Thu, 21 Nov 2019 12:55:29 -0800 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=IEWc4f3ewGXOvVCfqaCZhnhmSIZQffRVspuZA3WF20Dus0KzYtJwHLmC4kn3zFaK3yDWIdxNmNjfdpQks3NyUHcnFi80IaGTk/vf6w7Q4PUEBJkRL9JfU0q31Gj8kEYN3qeWJAzdqW0cbRBMnUz9oTZD14rJDAq7wSYMcGQUdxQJPfV8N1GIda3QqK0ulT3nQYGRElYj/ieUpBbuZXKWQOcpcXI54tPFKUQWTup53Z6qfFrZt/+9VyN6TIM9GqfKBKaEhaa3d7OQGQ3GGLDNmqfejY2km5enCjFYvpmQR6E49YU1GZA+HIh83srfE9lGcmthi0OtZc5YZCWiiGEY9Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=2OCbpaHS6orm4nl7xo5ZqCbhiUNlOOgT+wxlBshbgc8=; b=ermh/E5EGJ49jvP7d8caDkkfA8PQNQz0PXctRtwqHdcSBAbYwvR1bQjxW8tjumBxQXC5wMzrTFfuy705o4rp952dNKJZt7xSbYkt2nTMIaDJKd2VwsVOPEnkZQnisDo30tMJls+DeWyXtgx1Cs5qoJ1vLw8rzHUKahoYYIHnQ9CS9ZFQKESLkM0q45CE1OCUgw1+LJ8igZx996tqIiQuYJre+XI1B+vWizraL1b43SbX3w0WEaM92qKTY+LMh4H1PmW0L4QRFVWBl0TsZtQKDvzn0kHJBN2s+Bjp8RsYHFt+L36FAgMH0A188CZgzVZi+Av/UmLV4bDa5Pn6XQm+Fg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=fb.com; dmarc=pass action=none header.from=fb.com; dkim=pass header.d=fb.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.onmicrosoft.com; s=selector2-fb-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=2OCbpaHS6orm4nl7xo5ZqCbhiUNlOOgT+wxlBshbgc8=; b=Fr3iYi9AFlR6Iy/Iza6ebjFaMxVJeVxL1mJ6JmAI3qtEfagiSeL3QLzeJgDJcsndPkU6uSDaxWCNPRxfWElpS++fq/9vir7XIhZ61atht5LwXlwqBZBlb90GVK9DRsdweMXmi0aKQRa9Vtdwri4s/DmOv2ZC5XWHL8m4W5rVuUM= Received: from BYAPR15MB2631.namprd15.prod.outlook.com (20.179.156.24) by BYAPR15MB3430.namprd15.prod.outlook.com (20.179.57.89) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2474.17; Thu, 21 Nov 2019 20:55:27 +0000 Received: from BYAPR15MB2631.namprd15.prod.outlook.com ([fe80::fd23:27b9:7fe4:f4ac]) by BYAPR15MB2631.namprd15.prod.outlook.com ([fe80::fd23:27b9:7fe4:f4ac%3]) with mapi id 15.20.2474.019; Thu, 21 Nov 2019 20:55:27 +0000 From: Roman Gushchin To: Rik van Riel CC: Christian Borntraeger , "akpm@linux-foundation.org" , "hannes@cmpxchg.org" , Kernel Team , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "longman@redhat.com" , "shakeelb@google.com" , "vdavydov.dev@gmail.com" , Heiko Carstens , Janosch Frank , "kvm@vger.kernel.org" Subject: Re: WARNING bisected (was Re: [PATCH v7 08/10] mm: rework non-root kmem_cache lifecycle management) Thread-Topic: WARNING bisected (was Re: [PATCH v7 08/10] mm: rework non-root kmem_cache lifecycle management) Thread-Index: AQHVoF1eUJGIXl/jo02oA2+fhmBRU6eV2PaAgAAAgACAAB16AIAAINyAgAADcQA= Date: Thu, 21 Nov 2019 20:55:27 +0000 Message-ID: <20191121205520.GA5815@localhost.localdomain> References: <20190611231813.3148843-9-guro@fb.com> <20191121111739.3054-1-borntraeger@de.ibm.com> <20191121165807.GA201621@localhost.localdomain> <20191121184524.GA4758@localhost.localdomain> <30a2e4babdcb22974a0a5ae8c5e764d951eef7dc.camel@fb.com> In-Reply-To: <30a2e4babdcb22974a0a5ae8c5e764d951eef7dc.camel@fb.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: CO2PR18CA0051.namprd18.prod.outlook.com (2603:10b6:104:2::19) To BYAPR15MB2631.namprd15.prod.outlook.com (2603:10b6:a03:152::24) x-ms-exchange-messagesentrepresentingtype: 1 x-originating-ip: [2620:10d:c090:180::cf11] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: cb718519-ad61-47ee-b507-08d76ec522e1 x-ms-traffictypediagnostic: BYAPR15MB3430: x-ms-exchange-transport-forked: True x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:8882; x-forefront-prvs: 0228DDDDD7 x-forefront-antispam-report: SFV:NSPM;SFS:(10019020)(39860400002)(396003)(376002)(136003)(346002)(366004)(199004)(189003)(81166006)(8676002)(71190400001)(71200400001)(86362001)(66946007)(305945005)(7736002)(64756008)(256004)(66446008)(66556008)(66476007)(7416002)(6116002)(81156014)(33656002)(6486002)(229853002)(54906003)(25786009)(316002)(6636002)(6436002)(2906002)(99286004)(6246003)(1076003)(5660300002)(14454004)(11346002)(4744005)(446003)(4326008)(6862004)(478600001)(4001150100001)(186003)(102836004)(6512007)(9686003)(76176011)(52116002)(6506007)(8936002)(386003)(46003);DIR:OUT;SFP:1102;SCL:1;SRVR:BYAPR15MB3430;H:BYAPR15MB2631.namprd15.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;A:1;MX:1; received-spf: None (protection.outlook.com: fb.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: +E05oWs2/WQr9DqHPa8rJnquHlhgZ3JgDVDYNzNNq7h/H3T8ZcOT+jH8DbqT5c8ifchXz9JgASOVm4lMymh3WOHl7QRxsSPxns3Ky5d/0sNaBxhAIfIcjZZhhs1OkFioMLNxzj494c+V5lB+Xi83OtDE7V6YdycQwVi4b75yh6kaiCQeASAaWeiXbw/oSxKYFnmqheiQ8+ry/NUe5UQxjgolqpxuMVvCbTRe8SZwGvWJ+39rXEC18NukgdDSpFtFvM4a+87BHl7mEiHpRFTbIX05DjS5aELwtGXO/cs3juxj1lkvl73uHk+//F2laQspCXFxPakrpcfxcjl5iK4ajUmQYojHt6ElZ6N9G3QyNvB30iYeC69mWh8czFT+bHvLeJzJu3nFZXC97c3aveLeDyCM3oNVckCo8IYv7cROwqSKRlAG/Bf63E9kun29qRyt Content-Type: text/plain; charset="us-ascii" Content-ID: <682C7C080732E2458F4105B43CA71D10@namprd15.prod.outlook.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: cb718519-ad61-47ee-b507-08d76ec522e1 X-MS-Exchange-CrossTenant-originalarrivaltime: 21 Nov 2019 20:55:27.1682 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: Ic21n3x4juYwU6eCyapD4FoG35NweOebiMKQTo71uhZm6fXj5RO9o/FMX2RRDYqL X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR15MB3430 X-OriginatorOrg: fb.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,18.0.572 definitions=2019-11-21_06:2019-11-21,2019-11-21 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 adultscore=0 impostorscore=0 lowpriorityscore=0 spamscore=0 bulkscore=0 mlxscore=0 suspectscore=0 mlxlogscore=999 clxscore=1015 malwarescore=0 phishscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1911210174 X-FB-Internal: deliver X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Nov 21, 2019 at 12:43:01PM -0800, Rik van Riel wrote: > On Thu, 2019-11-21 at 13:45 -0500, Roman Gushchin wrote: > > On Thu, Nov 21, 2019 at 05:59:54PM +0100, Christian Borntraeger > > wrote: > > >=20 > > >=20 > > > Yes, rmmod has to be called directly after the guest shutdown to > > > see the issue. > > > See my 2nd mail. > >=20 > > I see. Do you know, which kmem_cache it is? If not, can you, please, > > figure it out? > >=20 > > I tried to reproduce the issue, but wasn't successful so far. So I > > wonder > > what can make your case special. >=20 > I do not know either, but have a guess. >=20 > My guess would be that either the slab object or the > slab page is RCU freed, and the kmem_cache destruction > is called before that RCU callback has completed. >=20 I've a reproducer, but it requires SLAB_TYPESAFE_BY_RCU to panic. The only question is if it's the same or different issues. As soon as I'll have a fix, I'll post it here to test. Thanks!