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_PASS,USER_AGENT_MUTT 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 3EAD5C0044B for ; Wed, 13 Feb 2019 21:13:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 12290218EA for ; Wed, 13 Feb 2019 21:13:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2394747AbfBMVNm (ORCPT ); Wed, 13 Feb 2019 16:13:42 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:38194 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727469AbfBMVNm (ORCPT ); Wed, 13 Feb 2019 16:13:42 -0500 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x1DL9lMw047911 for ; Wed, 13 Feb 2019 16:13:40 -0500 Received: from e06smtp02.uk.ibm.com (e06smtp02.uk.ibm.com [195.75.94.98]) by mx0b-001b2d01.pphosted.com with ESMTP id 2qmtg7s8e2-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 13 Feb 2019 16:13:40 -0500 Received: from localhost by e06smtp02.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) Wed, 13 Feb 2019 21:13:34 -0000 Received: from d06av21.portsmouth.uk.ibm.com (d06av21.portsmouth.uk.ibm.com [9.149.105.232]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x1DLDXou55836754 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 13 Feb 2019 21:13:33 GMT Received: from d06av21.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 711675204E; Wed, 13 Feb 2019 21:13:33 +0000 (GMT) Received: from rapoport-lnx (unknown [9.148.207.163]) by d06av21.portsmouth.uk.ibm.com (Postfix) with ESMTPS id 016D85204F; Wed, 13 Feb 2019 21:13:31 +0000 (GMT) Date: Wed, 13 Feb 2019 23:13:29 +0200 From: Mike Rapoport To: Andrew Morton Cc: Rob Herring , Marc Gonzalez , Frank Rowand , Marek Szyprowski , Catalin Marinas , Prateek Patel , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3] of: fix kmemleak crash caused by imbalance in early memory reservation References: <20190213181921.GB15270@rapoport-lnx> <20190213121237.b6df41e4fb6317e58c0716a3@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190213121237.b6df41e4fb6317e58c0716a3@linux-foundation.org> User-Agent: Mutt/1.5.24 (2015-08-30) X-TM-AS-GCONF: 00 x-cbid: 19021321-0008-0000-0000-000002C0241A X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19021321-0009-0000-0000-0000222C4413 Message-Id: <20190213211329.GD15270@rapoport-lnx> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-02-13_12:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=985 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1902130140 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 13, 2019 at 12:12:37PM -0800, Andrew Morton wrote: > On Wed, 13 Feb 2019 20:19:22 +0200 Mike Rapoport wrote: > > > > > Marc Gonzalez reported the following kmemleak crash: > > > > Unable to handle kernel paging request at virtual address ffffffc021e00000 > > Mem abort info: > > ESR = 0x96000006 > > Exception class = DABT (current EL), IL = 32 bits > > SET = 0, FnV = 0 > > EA = 0, S1PTW = 0 > > Data abort info: > > ISV = 0, ISS = 0x00000006 > > CM = 0, WnR = 0 > > swapper pgtable: 4k pages, 39-bit VAs, pgdp = (____ptrval____) > > [ffffffc021e00000] pgd=000000017e3ba803, pud=000000017e3ba803, > > pmd=0000000000000000 > > Internal error: Oops: 96000006 [#1] PREEMPT SMP > > Modules linked in: > > CPU: 6 PID: 523 Comm: kmemleak Tainted: G S W 5.0.0-rc1 #13 > > Hardware name: Qualcomm Technologies, Inc. MSM8998 v1 MTP (DT) > > pstate: 80000085 (Nzcv daIf -PAN -UAO) > > pc : scan_block+0x70/0x190 > > lr : scan_block+0x6c/0x190 > > sp : ffffff8012e8bd20 > > x29: ffffff8012e8bd20 x28: ffffffc0fdbaf018 > > x27: ffffffc022000000 x26: 0000000000000080 > > x25: ffffff8011aadf70 x24: ffffffc0f8cc8000 > > x23: ffffff8010dc8000 x22: ffffff8010dc8830 > > x21: ffffffc021e00ff9 x20: ffffffc0f8cc8050 > > x19: ffffffc021e00000 x18: 0000000000002409 > > x17: 0000000000000200 x16: 0000000000000000 > > x15: ffffff8010e14dd8 x14: 0000000000002406 > > x13: 000000004c4dd0c6 x12: ffffffc0f77dad58 > > x11: 0000000000000001 x10: ffffff8010d9e688 > > x9 : ffffff8010d9f000 x8 : ffffff8010d9e688 > > x7 : 0000000000000002 x6 : 0000000000000000 > > x5 : ffffff8011511c20 x4 : 00000000000026d1 > > x3 : ffffff8010e14d88 x2 : 5b36396f4e7d4000 > > x1 : 0000000000208040 x0 : 0000000000000000 > > Process kmemleak (pid: 523, stack limit = 0x(____ptrval____)) > > Call trace: > > scan_block+0x70/0x190 > > scan_gray_list+0x108/0x1c0 > > kmemleak_scan+0x33c/0x7c0 > > kmemleak_scan_thread+0x98/0xf0 > > kthread+0x11c/0x120 > > ret_from_fork+0x10/0x1c > > Code: f9000fb4 d503201f 97ffffd2 35000580 (f9400260) > > ---[ end trace 176d6ed9d86a0c33 ]--- > > note: kmemleak[523] exited with preempt_count 2 > > > > The crash happens when a no-map area is allocated in > > early_init_dt_alloc_reserved_memory_arch(). The allocated region is > > registered with kmemleak, but it is then removed from memblock using > > memblock_remove() that is not kmemleak-aware. > > > > Replacing memblock_phys_alloc_range() with memblock_find_in_range() makes > > sure that the allocated memory is not added to kmemleak and then > > memblock_remove()'ing this memory is safe. > > > > As a bonus, since memblock_find_in_range() ensures the allocation in the > > specified range, the bounds check can be removed. > > hm, why is this against -mm rather than against mainline? > > Do the OF maintainers intend to merge the fix? There's a conflict this fix and resent memblock related changes in -mm. Rob said he anyway wasn't planning to to send this for 5.0 [1] and suggested to merge it via your tree. [1] https://lore.kernel.org/lkml/CAL_JsqK-cC6oVZ9MkP+ExOGjCRhA0XxGSgqGKL3W9bFF3rKAgA@mail.gmail.com/ > > Thanks. > -- Sincerely yours, Mike.