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, 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 5976DC2BA19 for ; Tue, 14 Apr 2020 09:56:41 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E3FFE2064A for ; Tue, 14 Apr 2020 09:56:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=bytedance-com.20150623.gappssmtp.com header.i=@bytedance-com.20150623.gappssmtp.com header.b="qhOQagm3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E3FFE2064A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=bytedance.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 84B9A8E0003; Tue, 14 Apr 2020 05:56:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7FC478E0001; Tue, 14 Apr 2020 05:56:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6C46B8E0003; Tue, 14 Apr 2020 05:56:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0216.hostedemail.com [216.40.44.216]) by kanga.kvack.org (Postfix) with ESMTP id 5160C8E0001 for ; Tue, 14 Apr 2020 05:56:40 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 109EC18107DF1 for ; Tue, 14 Apr 2020 09:56:40 +0000 (UTC) X-FDA: 76706006160.02.flesh74_1d0a69048504b X-HE-Tag: flesh74_1d0a69048504b X-Filterd-Recvd-Size: 3609 Received: from mail-il1-f193.google.com (mail-il1-f193.google.com [209.85.166.193]) by imf28.hostedemail.com (Postfix) with ESMTP for ; Tue, 14 Apr 2020 09:56:39 +0000 (UTC) Received: by mail-il1-f193.google.com with SMTP id e4so9078243ils.4 for ; Tue, 14 Apr 2020 02:56:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=8mTNRog1G9NWOtzic5n9BO42Qp3FLPijpt9pvlrD31Y=; b=qhOQagm3THBbvlxAE3Rn2heuILfmBp/l1AIRXXRKjGasf3aAUh7sEfVQcTOkl3HwA5 AGOughY6DCPGc/MuRrrmAFSKnzurk90fqFyOlR50UlCDAoK4cl3BWzQAigY91SGhfMVm VCCh+QvAUgargxxeOpEtPmYiENOydD04UFelLdKRaXnUliSeaXDvANSzYewCSFyWSdaE OkUSvoda9SV5uw0f3O0Hb+9uV4KZ5Sbe5dThWCsE3Y0MVbKtj757hZ9+smGcLWmnFhIa YhTuXG1AOnrRllRakaOz0zBgCYvhr3hxDzKYy2JAz7DFNkmEQzLc4xHzQrMCTiW6HBOl 1Oxg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=8mTNRog1G9NWOtzic5n9BO42Qp3FLPijpt9pvlrD31Y=; b=PNqrZqW9c37pJAbxf0NX2kbVsk1En2Y7AgKCmGIxP/Br5vwk5d6bU1uvcJGsyapbhA XynWBqhhOiuEbAZCmDaZlv7UbJ4WtuLofaBX+r1wypach4ewHy0qO9Nrs6RqMRBNEKlp rH9plED7G9HHYk/2z8Jn+KEV+967TkIp3E+S1s3lWwzQ0yve36ATY2bf7pZ6Rm4+9ShT 6PzVZ3uoPtCmVCC7o4RYpDNfhK8L5xbtFVRzZ99jU2fNs9ldsZ9rMSvmBfZT+EwtofTQ cMjsTYOE7gDCSEnmiTID5kZkHp+MEHnGsnxhDeboPW71+9pb3/KQLzjYIVwBEi/WP045 wb4A== X-Gm-Message-State: AGi0PuZDwLeMh2SUtCxPbGSIuJDpubpnc1ZUxIW2dS7vU20sSmNu+YLo 57BWG0Ewc1bXqnRVVzWue4x7jLrAnEIAh2yoIIwsTg== X-Google-Smtp-Source: APiQypLc7vO+U+uz9b8s/sGSMGpFqNHTJ9dIn0wIr4ttnCsma2EKuI05wVk56hvQwfQo+bBCeyWmIxzGlNztFQeLPM0= X-Received: by 2002:a92:5f17:: with SMTP id t23mr7609747ilb.2.1586858198824; Tue, 14 Apr 2020 02:56:38 -0700 (PDT) MIME-Version: 1.0 References: <20200414075622.69822-1-songmuchun@bytedance.com> In-Reply-To: From: Muchun Song Date: Tue, 14 Apr 2020 17:56:02 +0800 Message-ID: Subject: Re: [External] Re: [PATCH v2] mm/ksm: Fix NULL pointer dereference when KSM zero page is enabled To: Markus Elfring Cc: Xiongchun Duan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrew Morton Content-Type: text/plain; charset="UTF-8" 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 Tue, Apr 14, 2020 at 5:17 PM Markus Elfring wrote: > > > to crash when we access vma->vm_mm(its offset is 0x40) later in > > Will another fine-tuning become relevant also for this wording? > Sorry, I don't understand what this means because of my poor English. Could you explain it again. Thanks. > > > following calltrace is captured in kernel 4.19 with KSM zero page > > Can the mentioned Linux version trigger any special software > development concerns? > > Will any other tags become helpful in such a case? How about changing "following calltrace is captured in kernel 4.19 with KSM zero page" to "The following calltrace is captured with the following patch applied: e86c59b1b12d ("mm/ksm: improve deduplication of zero pages with colouring") " ? -- Yours, Muchun