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=-6.7 required=3.0 tests=FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 573D4C10F27 for ; Mon, 9 Mar 2020 13:56:58 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id F179C20848 for ; Mon, 9 Mar 2020 13:56:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F179C20848 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=hotmail.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 4960F6B0005; Mon, 9 Mar 2020 09:56:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 447DF6B0006; Mon, 9 Mar 2020 09:56:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 337046B0007; Mon, 9 Mar 2020 09:56:57 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0090.hostedemail.com [216.40.44.90]) by kanga.kvack.org (Postfix) with ESMTP id 1D4066B0005 for ; Mon, 9 Mar 2020 09:56:57 -0400 (EDT) Received: from smtpin19.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id C68654995FD for ; Mon, 9 Mar 2020 13:56:56 +0000 (UTC) X-FDA: 76575974832.19.lamp11_1f7056fed1452 X-HE-Tag: lamp11_1f7056fed1452 X-Filterd-Recvd-Size: 8824 Received: from EUR05-DB8-obe.outbound.protection.outlook.com (mail-db8eur05olkn2031.outbound.protection.outlook.com [40.92.89.31]) by imf26.hostedemail.com (Postfix) with ESMTP for ; Mon, 9 Mar 2020 13:56:55 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Z6WTAis9vkniD1rAvb5y3z3wX6r0wjcdC33gHSae6T1DHzEZTcbdVOvSMG9G+fc3K7BAIHWl6ztsFeLuHpH3tZZMOAraF6KCk9lnUIE+tEJqyum/zz865uCqmq5wA5j9bATjARFXuzykvmuuv2eSzI0UGi9mLShsGCDb01olhkBEu5ZKSeH1kCjsFuMk5aOMH1iWtZW3qKBsMkN5xTjsBS48DFALmXhiRGW/4td9a1E9JdxekNyFE08MYlxcU8C6ZrNQilhiIY5dEdyV8r/1dduV2SokfALZ6I9Z8jF9ulxgjx5lPomwTSPouE97X07wLd2UKlm0U6ZJ/xQL2SBaFQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=Yi8+Ifj7+IVwk8cKLYgjMHk+362bsnsvCoRPq48uwvQ=; b=jMQUHKZmkP2Xl5Nd0WVbRY+CTrVRY+qlAz7MyYeWg4e6XwK96G41vLVpDdXl+ZdFYt1L552tSA9wnQqNxC8wjRee3Kh0tnNpcpU0GvDIcHqNlwHwB9pWVsPJtiGMqu0dnMUZl+11n5njilqJL7RV91L2cTSSt0Xo5qhfKZ2lXTeJMS4i0/dqdYxt5Fq6fwHgii9TYMVOeaFJPvWd1VDyPQSHbrU/SOpBSGLJzKLl3MCWnUzjOp957L4a5kjhDRoKh7JWZMdvV7e1nk1b/jRN9PzeQwzJ3k7PvipuUXTRV4WRBxGbW/wK7aE8fm0wo678j9WnWuYs8MRgMzMjUEyeNQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=none; dmarc=none; dkim=none; arc=none Received: from AM6EUR05FT032.eop-eur05.prod.protection.outlook.com (2a01:111:e400:fc11::3a) by AM6EUR05HT249.eop-eur05.prod.protection.outlook.com (2a01:111:e400:fc11::335) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2793.11; Mon, 9 Mar 2020 13:56:54 +0000 Received: from AM6PR03MB5170.eurprd03.prod.outlook.com (10.233.240.56) by AM6EUR05FT032.mail.protection.outlook.com (10.233.240.101) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2793.11 via Frontend Transport; Mon, 9 Mar 2020 13:56:54 +0000 Received: from AM6PR03MB5170.eurprd03.prod.outlook.com ([fe80::1956:d274:cab3:b4dd]) by AM6PR03MB5170.eurprd03.prod.outlook.com ([fe80::1956:d274:cab3:b4dd%6]) with mapi id 15.20.2772.019; Mon, 9 Mar 2020 13:56:54 +0000 Received: from [192.168.1.101] (92.77.140.102) by ZR0P278CA0047.CHEP278.PROD.OUTLOOK.COM (2603:10a6:910:1d::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2793.15 via Frontend Transport; Mon, 9 Mar 2020 13:56:52 +0000 From: Bernd Edlinger To: "Eric W. Biederman" CC: Christian Brauner , Kees Cook , Jann Horn , Jonathan Corbet , Alexander Viro , Andrew Morton , Alexey Dobriyan , Thomas Gleixner , Oleg Nesterov , Frederic Weisbecker , Andrei Vagin , Ingo Molnar , "Peter Zijlstra (Intel)" , Yuyang Du , David Hildenbrand , Sebastian Andrzej Siewior , Anshuman Khandual , David Howells , James Morris , Greg Kroah-Hartman , Shakeel Butt , Jason Gunthorpe , Christian Kellner , Andrea Arcangeli , Aleksa Sarai , "Dmitry V. Levin" , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "linux-mm@kvack.org" , "stable@vger.kernel.org" , "linux-api@vger.kernel.org" Subject: Re: [PATCH v2 1/5] exec: Only compute current once in flush_old_exec Thread-Topic: [PATCH v2 1/5] exec: Only compute current once in flush_old_exec Thread-Index: AQHV9ZHPFX16pJkAgEa5cakb87d5R6hASgaA Date: Mon, 9 Mar 2020 13:56:54 +0000 Message-ID: References: <87v9nmjulm.fsf@x220.int.ebiederm.org> <202003021531.C77EF10@keescook> <20200303085802.eqn6jbhwxtmz4j2x@wittgenstein> <87v9nlii0b.fsf@x220.int.ebiederm.org> <87a74xi4kz.fsf@x220.int.ebiederm.org> <87r1y8dqqz.fsf@x220.int.ebiederm.org> <87tv32cxmf.fsf_-_@x220.int.ebiederm.org> <87v9ne5y4y.fsf_-_@x220.int.ebiederm.org> <87pndm5y3l.fsf_-_@x220.int.ebiederm.org> In-Reply-To: <87pndm5y3l.fsf_-_@x220.int.ebiederm.org> Accept-Language: en-US, en-GB, de-DE Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: ZR0P278CA0047.CHEP278.PROD.OUTLOOK.COM (2603:10a6:910:1d::16) To AM6PR03MB5170.eurprd03.prod.outlook.com (2603:10a6:20b:ca::23) x-incomingtopheadermarker: OriginalChecksum:B515126297876112A916F44DFDB18DD9BFDBD252421E38E513258B332AB5B72C;UpperCasedChecksum:C3A00DC04B939B54E45B83C53CBF058525589B878FBDAEF83C6AC291945DED88;SizeAsReceived:9855;Count:50 x-ms-exchange-messagesentrepresentingtype: 1 x-tmn: [K825C0teb3P5ZldLrD3eKiX488msngkX] x-microsoft-original-message-id: x-ms-publictraffictype: Email x-incomingheadercount: 50 x-eopattributedmessage: 0 x-ms-office365-filtering-correlation-id: aa99d3ea-e3b2-492e-dfe3-08d7c431b987 x-ms-traffictypediagnostic: AM6EUR05HT249: x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: N29AFT5gwOdXOw4Ift49nAsui4EvcbcVwrocPIbUJxnOplygYGoostbkPz3VwpBrlE4fmlUqDbqlRtCUgO2TFSllAzW0dAQRKueAgTxI5RmdcJsqC3RmuHfAsnvRmCorQ0E57P66gJTqub6d3vWW1IwY1vGFuEpbal2Sj2fYz/oCuS3/MnDygk5wSxr4MFvB x-ms-exchange-antispam-messagedata: CAXBwo9svyP7QuhSTsiq2S2ZAE3T/XRuhCoQdJ/s0j1smOu3w6NKWyNxuBiGYGFwiF01/Bu1Yr3cZsf9c6Oum9XreIgdOWgr0lHIQeVg5ntrr69H5bYPMSLr2kscu8UQPMZ3qUSbqTA9TSWOS4oHuw== x-ms-exchange-transport-forked: True Content-Type: text/plain; charset="Windows-1252" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: outlook.com X-MS-Exchange-CrossTenant-RMS-PersistedConsumerOrg: 00000000-0000-0000-0000-000000000000 X-MS-Exchange-CrossTenant-Network-Message-Id: aa99d3ea-e3b2-492e-dfe3-08d7c431b987 X-MS-Exchange-CrossTenant-rms-persistedconsumerorg: 00000000-0000-0000-0000-000000000000 X-MS-Exchange-CrossTenant-originalarrivaltime: 09 Mar 2020 13:56:54.5613 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Internet X-MS-Exchange-CrossTenant-id: 84df9e7f-e9f6-40af-b435-aaaaaaaaaaaa X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM6EUR05HT249 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 3/8/20 10:35 PM, Eric W. Biederman wrote: >=20 > Make it clear that current only needs to be computed once in > flush_old_exec. This may have some efficiency improvements and it > makes the code easier to change. >=20 > Signed-off-by: "Eric W. Biederman" > --- > fs/exec.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) >=20 > diff --git a/fs/exec.c b/fs/exec.c > index db17be51b112..c3f34791f2f0 100644 > --- a/fs/exec.c > +++ b/fs/exec.c > @@ -1260,13 +1260,14 @@ void __set_task_comm(struct task_struct *tsk, con= st char *buf, bool exec) > */ > int flush_old_exec(struct linux_binprm * bprm) > { > + struct task_struct *me =3D current; > int retval; > =20 > /* > * Make sure we have a private signal table and that > * we are unassociated from the previous thread group. > */ > - retval =3D de_thread(current); > + retval =3D de_thread(me); > if (retval) > goto out; > =20 > @@ -1294,10 +1295,10 @@ int flush_old_exec(struct linux_binprm * bprm) > bprm->mm =3D NULL; > =20 > set_fs(USER_DS); > - current->flags &=3D ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD | > + me->flags &=3D ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD | > PF_NOFREEZE | PF_NO_SETAFFINITY); I wonder if this line should be aligned with the previous? Bernd.