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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 56CBFC49ED7 for ; Fri, 13 Sep 2019 11:12:47 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 21C07208C0 for ; Fri, 13 Sep 2019 11:12:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 21C07208C0 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=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 917C96B0008; Fri, 13 Sep 2019 07:12:46 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8C8486B000A; Fri, 13 Sep 2019 07:12:46 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7DD2C6B000C; Fri, 13 Sep 2019 07:12:46 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0146.hostedemail.com [216.40.44.146]) by kanga.kvack.org (Postfix) with ESMTP id 5AEE76B0008 for ; Fri, 13 Sep 2019 07:12:46 -0400 (EDT) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with SMTP id E499220BEE for ; Fri, 13 Sep 2019 11:12:45 +0000 (UTC) X-FDA: 75929634690.13.look40_18172ec593e08 X-HE-Tag: look40_18172ec593e08 X-Filterd-Recvd-Size: 5082 Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by imf15.hostedemail.com (Postfix) with ESMTP for ; Fri, 13 Sep 2019 11:12:45 +0000 (UTC) Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x8DBCOfg035064 for ; Fri, 13 Sep 2019 07:12:42 -0400 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 2v0923tetq-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 13 Sep 2019 07:12:42 -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, 13 Sep 2019 12:12:38 +0100 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x8DBCbUF28901630 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 13 Sep 2019 11:12:37 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 53B9FA405F; Fri, 13 Sep 2019 11:12:37 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D8B57A4060; Fri, 13 Sep 2019 11:12:36 +0000 (GMT) Received: from pomme.local (unknown [9.145.117.92]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 13 Sep 2019 11:12:36 +0000 (GMT) Subject: Re: Speculative page faults To: zhong jiang Cc: Vinayak Menon , Linux-MM , "Wangkefeng (Kevin)" , charante@codeaurora.org References: <5D74BC65.4070309@huawei.com> From: Laurent Dufour Date: Fri, 13 Sep 2019 13:12:36 +0200 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <5D74BC65.4070309@huawei.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US X-TM-AS-GCONF: 00 x-cbid: 19091311-0012-0000-0000-0000034AD318 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19091311-0013-0000-0000-0000218542DF Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-09-13_06:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=657 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1909130108 Content-Transfer-Encoding: quoted-printable 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: Le 08/09/2019 =C3=A0 10:31, zhong jiang a =C3=A9crit=C2=A0: > Hi, Laurent, Vinayak >=20 > I have got the following crash on 4.14 kernel with speculative page fau= lts enabled. > Unfortunately, The issue disappears when trying disabling SPF. Hi Zhong, Sorry for to late answer, I was busy at the LPC. I never hit that. Is there any steps identified leading to this crash ? Thanks, Laurent. > The call trace is as follows. >=20 > Unable to handle kernel NULL pointer dereference at virtual address 000= 00000 > user pgtable: 4k pages, 39-bit VAs, pgd =3D ffffffc177337000 > [0000000000000000] *pgd=3D0000000177346003, *pud=3D0000000177346003, *p= md=3D0000000000000000 > Internal error: Oops: 96000046 [#1] PREEMPT SMP >=20 > CPU: 0 PID: 3184 Comm: Signal Catcher VIP: 00 Tainted: G O = 4.14.116 #1 > PC is at __rb_erase_color+0x54/0x260 > LR is at anon_vma_interval_tree_remove+0x2ac/0x2c0 >=20 > Call trace: > [] __rb_erase_color+0x54/0x260 > [] anon_vma_interval_tree_remove+0x2ac/0x2c0 > [] unlink_anon_vmas+0x84/0x170 > [] free_pgtables+0x9c/0x100 > [] exit_mmap+0xb0/0x1d8 > [] mmput+0x3c/0xe0 > [ffffff800822ed00>] do_exit+0x2f0/0x954 > [] do_group_exit+0x88/0x9c > [] get_signal+0x360/0x56c > [] do_notify_resume+0x150/0x5e4 > Exception stack(0xffffffc1eac07ec0 to 0xffffffc1eac08000) >=20 > It seems to rb_node is empty accidentally under anon_vma rwsem when the= process is exiting. > I have no idea whether any race existence or not to result in the issue= . >=20 > Let me know if you have hit the issue or any suggestions. >=20 > Thanks, > zhong jiang >=20