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[2620:137:e000::1:18]) by mx.google.com with ESMTPS id rj7-20020a17090b3e8700b001dfa650a00asi1424153pjb.149.2022.05.17.20.35.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 May 2022 20:35:17 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:18 as permitted sender) client-ip=2620:137:e000::1:18; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20210112 header.b=NorNrwCZ; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 575AD7093C; Tue, 17 May 2022 20:25:57 -0700 (PDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233213AbiERBEw (ORCPT + 99 others); Tue, 17 May 2022 21:04:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53704 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230105AbiERBEv (ORCPT ); Tue, 17 May 2022 21:04:51 -0400 Received: from mail-ed1-x52b.google.com (mail-ed1-x52b.google.com [IPv6:2a00:1450:4864:20::52b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F375C5401B; Tue, 17 May 2022 18:04:49 -0700 (PDT) Received: by mail-ed1-x52b.google.com with SMTP id er5so1039731edb.12; Tue, 17 May 2022 18:04:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=cGbIZ0WjSw2ZJa647FvL8buifxBLVMmodCe2ePJMeJM=; b=NorNrwCZP1aJ/u2RVDG9zK0qpsF3l1n2Vx79ANbCZTXP1MuDNkyoGmYJE3J4L2g6JF ZD80dJOmGCe2z4I8I7bizk/FHdX0bwcCt+dEcYAFmltKL6f8/rZnktPPuFPHwDFMzCPB rDuNjFOeNv9W0gufxxvk0CI7C8P7qfQOwkGBkAYPsXa9FHjHognB0BqIFrZ+GMCTOpLi eNjxITHqU9P5GRBwcnCsywD8kPBTu68U83wkRuZ3B/pCwtCgw+gIpZLmPIDvbeK6tVxO afFPfkpp2D5HTzX6DbC6wQOuUi++Ma6gAjtloUl3vUjphBPvbXEBC/kVnZ2nS/lmuXG3 gGQw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=cGbIZ0WjSw2ZJa647FvL8buifxBLVMmodCe2ePJMeJM=; b=KIFpT+VDtZLHJ87h7i0VElMQSWwDu2gOusN+um6KePa4wevq0ObclVum67GOfhlB4o itiJBRkmQT90X9jWNAx/kxUTiQmS5X47/FUjOP99bYa6UpoiqfCa1hS8HGjRVCvJtxse TDlTYVy7U1WoHvWt+D+P2KuuuQhIyQ7uIati0EqgD4MT2/y23Z39HgAvopv2ZL0yg4m6 wyzGTvWz6UCAC7kOtby6V9f9JDkxLWOKGMKedCf/iAEwp4gqd+m+vf4hiGuzFjggJ5pZ gsibnZqHqsfqy/Lf0X+bFnjJjMFWRJ1PL0I0M6LLS0vUHbbv/hNE+GmTmmKxSmlEh9W/ e9Og== X-Gm-Message-State: AOAM530zRWvNrvhRnvhg3zeyp8E6ehaPGs20d9d3Hx68KEXfESn0I9vU 6cVY1uc/kLnhu3IXJMom+vNmLRiMJYo/CFIgxyU= X-Received: by 2002:a05:6402:176b:b0:42a:a828:5d79 with SMTP id da11-20020a056402176b00b0042aa8285d79mr17334145edb.272.1652835888521; Tue, 17 May 2022 18:04:48 -0700 (PDT) MIME-Version: 1.0 References: <20220517073106.1704628-1-zhangshida@kylinos.cn> In-Reply-To: From: Stephen Zhang Date: Wed, 18 May 2022 09:04:12 +0800 Message-ID: Subject: Re: [PATCH] cgroup: fix potential null pointer risk To: Tejun Heo Cc: lizefan.x@bytedance.com, hannes@cmpxchg.org, zhangshida , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-1.7 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RDNS_NONE, SPF_HELO_NONE,T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Tejun Heo =E4=BA=8E2022=E5=B9=B45=E6=9C=8818=E6=97=A5=E5=91= =A8=E4=B8=89 01:07=E5=86=99=E9=81=93=EF=BC=9A > > The function is never called for a root cgroup. The parent check up above= in > the same function is superflous. So, maybe remove that? > > Thanks. > > -- > tejun Thanks. I will remake a patch based on this. -- Stephen