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=-3.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 3FB0EC433E1 for ; Tue, 18 Aug 2020 02:25:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0DB48206DA for ; Tue, 18 Aug 2020 02:25:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0DB48206DA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 92CD56B0002; Mon, 17 Aug 2020 22:25:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8B52A6B0005; Mon, 17 Aug 2020 22:25:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 780426B0006; Mon, 17 Aug 2020 22:25:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0008.hostedemail.com [216.40.44.8]) by kanga.kvack.org (Postfix) with ESMTP id 5EFFF6B0002 for ; Mon, 17 Aug 2020 22:25:58 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 20EEF3489 for ; Tue, 18 Aug 2020 02:25:58 +0000 (UTC) X-FDA: 77162099196.14.game96_010360a2701b Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin14.hostedemail.com (Postfix) with ESMTP id E631B18229818 for ; Tue, 18 Aug 2020 02:25:57 +0000 (UTC) X-HE-Tag: game96_010360a2701b X-Filterd-Recvd-Size: 2130 Received: from huawei.com (szxga01-in.huawei.com [45.249.212.187]) by imf27.hostedemail.com (Postfix) with ESMTP for ; Tue, 18 Aug 2020 02:25:57 +0000 (UTC) Received: from dggeme704-chm.china.huawei.com (unknown [172.30.72.54]) by Forcepoint Email with ESMTP id A351282782B86ACD5956; Tue, 18 Aug 2020 10:25:49 +0800 (CST) Received: from dggeme753-chm.china.huawei.com (10.3.19.99) by dggeme704-chm.china.huawei.com (10.1.199.100) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1913.5; Tue, 18 Aug 2020 10:25:49 +0800 Received: from dggeme753-chm.china.huawei.com ([10.7.64.70]) by dggeme753-chm.china.huawei.com ([10.7.64.70]) with mapi id 15.01.1913.007; Tue, 18 Aug 2020 10:25:49 +0800 From: linmiaohe To: Matthew Wilcox CC: "akpm@linux-foundation.org" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] mm/migrate: Avoid possible unnecessary ptrace_may_access() call in kernel_move_pages() Thread-Topic: [PATCH] mm/migrate: Avoid possible unnecessary ptrace_may_access() call in kernel_move_pages() Thread-Index: AdZ1Bqx0JUT5SU7CKEmLji2ne5ieMQ== Date: Tue, 18 Aug 2020 02:25:49 +0000 Message-ID: <8e7c7a77722446afbc8cb25e46eab325@huawei.com> Accept-Language: zh-CN, en-US Content-Language: zh-CN X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.174.176.142] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-CFilter-Loop: Reflected X-Rspamd-Queue-Id: E631B18229818 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam02 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: Matthew Wilcox wrote: >On Mon, Aug 17, 2020 at 07:59:33AM -0400, Miaohe Lin wrote: >> There is no need to check if this process has the right to modify the=20 >> specified process when they are same. > >We should probably also skip the security hook call if a process is modify= ing its own pages. > >How about this instead? > It sounds good, thanks for your good advice. Would you like a tag like sugg= est-by?