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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 E551AC433DF for ; Wed, 3 Jun 2020 19:47:00 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7C11020734 for ; Wed, 3 Jun 2020 19:47:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="clbGWIbT"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=synopsys.com header.i=@synopsys.com header.b="fAIzGl+c"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=synopsys.com header.i=@synopsys.com header.b="dr1SYZiF" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7C11020734 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=synopsys.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-snps-arc-bounces+linux-snps-arc=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Content-ID:In-Reply-To: References:Message-ID:Date:Subject:To:From:Reply-To:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=EzIkno7uUF2pTQJSpOX961ImSL2YMKnuSowv/+xIxCM=; b=clbGWIbTLDv7NG ysYd1/IthqaVLqq3jCqDATIqeauT8MnbdQfrL9cTnhFwYHvNMTFoD63KJnVzI5jzaE8LAxUFvye23 koqFYdjTJnR2FUW9vyVogYEhK/lmNkD/nZO0EvkTsqSudKQdvOMJG6Ugrl4YBaHGn1LnPyLWZt6EM YgxlRwcNYJI1gqCldhFXmHmCyA452xpZ0iikqlODhfTk3qBAVBrk42hiw/9AZzsvg5FGMDAa+0bVc FiYi+t6mo7wcabL9GA5kd7SG78rKsh1Gf6bNwr92xUoNvMQH06Q52BjB0a7bjiPptRm9XyIuXlj72 k+MrZQ38eFC3jda7zCuw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jgZLk-0000ad-5c; Wed, 03 Jun 2020 19:46:56 +0000 Received: from smtprelay-out1.synopsys.com ([149.117.73.133]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jgZLh-0000VF-4j for linux-snps-arc@lists.infradead.org; Wed, 03 Jun 2020 19:46:54 +0000 Received: from mailhost.synopsys.com (badc-mailhost2.synopsys.com [10.192.0.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by smtprelay-out1.synopsys.com (Postfix) with ESMTPS id BCD1B4017E; Wed, 3 Jun 2020 19:46:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=synopsys.com; s=mail; t=1591213585; bh=nOzEPv4G6lL0lY84NBsYrPZNylRObEdS7REbqn/ufa0=; h=From:To:CC:Subject:Date:References:In-Reply-To:From; b=fAIzGl+cdTAZ/loi2qMrkKOjrH+ENizFFfAuFaLDvnlmT7lL9tksu/sTKlzbvNeCC g6Z2LL3bkzLySchsrO/dZ4GhoP7gJ0IqD2YvegOmMhZhsOxDojg9WMfgkaVT2C6n0f rum48cegOb7pYGgOlTRKK4esnLvd2ecgMYdTVwrq2sEMHlvenmaSdy69Q32S/ThnNV zqozcp4K3fCbdrZ6Ey75PGIabnODkbiHwsq6w723slDDVXuansBxh4gypuE5IWbLTJ nYu4l7eOV1B2QmIDbd01hFFYpD8sfjuBLa3ZK1/IXcor5cvg/i2q2leDNLRoD6+c6Y 7Hp/96SE5tmIw== Received: from US01WEHTC3.internal.synopsys.com (us01wehtc3.internal.synopsys.com [10.15.84.232]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mailhost.synopsys.com (Postfix) with ESMTPS id 6996CA0067; Wed, 3 Jun 2020 19:46:16 +0000 (UTC) Received: from US01HYBRID2.internal.synopsys.com (10.15.246.24) by US01WEHTC3.internal.synopsys.com (10.15.84.232) with Microsoft SMTP Server (TLS) id 14.3.408.0; Wed, 3 Jun 2020 12:46:15 -0700 Received: from NAM12-BN8-obe.outbound.protection.outlook.com (10.202.3.67) by mrs.synopsys.com (10.15.246.24) with Microsoft SMTP Server (TLS) id 14.3.487.0; Wed, 3 Jun 2020 12:46:14 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Ohg1KJ+xCxSbDbsny5j8frcnUlxCF7FA41QkP6kNjEjXBU40QOdEaLEcQ44HZSDeb5WNsBq9js74JwGDb+FJndDUBUOVC6dkCrmp23BdTdu84gA2l6EW0XnKye9iQXI1t7H2Ecq2Zfek1ADnBv0IFBa8JTLg+a6iChRgk3kQoKbCUssmqcIZdHWRk/kyMlcinfgLpYj2AUKmytbT+11JxUoOdeCE7aWf3mSDryVR9KzzDnb/Hc2ZY6VDdevWXFjzs8pPqjW6Ve4QaC7oCGYhMewNu99i+bPksipptbA46ALtlMjjOWfQEvRn9B/3GDZEN6RoM2M5JNHPrtq8P6oHHA== 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=nOzEPv4G6lL0lY84NBsYrPZNylRObEdS7REbqn/ufa0=; b=h3b9kZjWT1tXougIpTXToUs+/yzxulO8j8RiqJTJMEQBo0Cw9NYmMOiehT8QWiVDIPbsMiP/mu8R7jRePRNW5YXgm7mJ/bZ5dFnK2xb5At9H8qAAsP0EQlVUx/9bZJ1p1b2Ei/iPiQirJ3FCmIkcA2J2o4+y6glj9FFikbnIbiXZo64+C/gOsMwRkkLJ/i+0PLkFX6C2GvbGqcHhraGokhV2GZqydtduHSJ/+EnDxubZsTsl/0ni7jau0tMGWQAJx6Xhfs+XT5m8D3l+aoQHpk+T+Q1uCaZ2yLVYgv51f0mp04D75+ikFaiNn4r57/JR0uK/kGTuJfDc2LPbBKr8NQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=synopsys.com; dmarc=pass action=none header.from=synopsys.com; dkim=pass header.d=synopsys.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=synopsys.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=nOzEPv4G6lL0lY84NBsYrPZNylRObEdS7REbqn/ufa0=; b=dr1SYZiFSRpAZiia+1OForbmJrUALreM0Mp2NuJoNp4rZguGI8Qikfe1lwnv9gGRRQhs6OZJbYtHz+ZJjC/9V+6c8/8UR+qH5sSiuJjFawX8kSA9j6ga8m4Q06EVOSqumFNFqotaQXK9YSKvsoh4J2PKTIePMePsX7KiKIQwuqg= Received: from BYAPR12MB3479.namprd12.prod.outlook.com (2603:10b6:a03:dc::26) by BYAPR12MB2710.namprd12.prod.outlook.com (2603:10b6:a03:68::11) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3066.18; Wed, 3 Jun 2020 19:46:12 +0000 Received: from BYAPR12MB3479.namprd12.prod.outlook.com ([fe80::a43a:7392:6fa:c6af]) by BYAPR12MB3479.namprd12.prod.outlook.com ([fe80::a43a:7392:6fa:c6af%6]) with mapi id 15.20.3045.024; Wed, 3 Jun 2020 19:46:12 +0000 X-SNPS-Relay: synopsys.com From: Vineet Gupta To: Adhemerval Zanella , Vineet Gupta , "libc-alpha@sourceware.org" Subject: Re: [PATCH v6 07/13] ARC: Linux Syscall Interface Thread-Topic: [PATCH v6 07/13] ARC: Linux Syscall Interface Thread-Index: AQHWNdk7jGc/VtI9YkWN6o0lqZFobKjHU5GA Date: Wed, 3 Jun 2020 19:46:12 +0000 Message-ID: References: <20200423014126.10417-1-vgupta@synopsys.com> <20200423014126.10417-8-vgupta@synopsys.com> <248259c7-8263-805d-56cd-9db397eb9c04@linaro.org> In-Reply-To: <248259c7-8263-805d-56cd-9db397eb9c04@linaro.org> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: user-agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 authentication-results: linaro.org; dkim=none (message not signed) header.d=none;linaro.org; dmarc=none action=none header.from=synopsys.com; x-originating-ip: [2601:641:c100:83a0:fee2:8ed0:e900:96d1] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 2d763437-0793-4715-a973-08d807f6c50f x-ms-traffictypediagnostic: BYAPR12MB2710: x-ms-exchange-transport-forked: True x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:5797; x-forefront-prvs: 04238CD941 x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: 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 x-forefront-antispam-report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:BYAPR12MB3479.namprd12.prod.outlook.com; PTR:; CAT:NONE; SFTY:; SFS:(376002)(396003)(39860400002)(366004)(346002)(136003)(76116006)(6506007)(66476007)(110136005)(53546011)(6512007)(66556008)(316002)(66946007)(66446008)(86362001)(64756008)(2616005)(4326008)(186003)(966005)(6486002)(31686004)(478600001)(2906002)(8936002)(71200400001)(8676002)(5660300002)(83380400001)(31696002)(4744005)(36756003)(533714002)(43740500002); DIR:OUT; SFP:1102; x-ms-exchange-antispam-messagedata: rhG0Dk4axG0WxYr9so+Iy5g3Gad8Aufgx3RU3JhjJyN2iVvr1iwIveDpQzEs0vnOQqXxho3pl8eyaNDCw3RiPB1tY8op4BUR866xoeUtZJpIEaX8XEfl58+kEeng5rrOMq6q1HiybcDJGLtigggQAX9haxrrk1OpJ/eAaAEYpkXo9xjS5MyKbhLbbkKh3GN8hZuXRKmbN165Xavwqv0N1qdyqQTHH1rs/FhKcbVU4bHE+4TeSDe0zF2exsMg1razMEvXBuKYfHHSVCoXomvLzHTlilpOO1WNJSX5xEULjG+/5HUKbqSaLeoyjekuvDF94aGbryJzitmvVlCaqmp+IHhWQh/1Ux3ZwKy7QIzNqOJVVl90GJ6dbgiluvZCOr1lebfbvZYehLXPF02ECYrRMNVDmsMzX8r2Sas82R+6DuJU85C6O+Bq4uFH3D7dHjPPYRa3Iqv8M6GLQyDak6qNcSW9GTfiOrAjWxAub1RnlzTZXOvqdniicMv6aRTS6CYwYKw3ISCKyv6mn3nKTK8ohPHh6KGt3XGscIa69N9GH5CcAmkCt2Ctb0/5zpW9QYYS Content-ID: MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: 2d763437-0793-4715-a973-08d807f6c50f X-MS-Exchange-CrossTenant-originalarrivaltime: 03 Jun 2020 19:46:12.0823 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: c33c9f88-1eb7-4099-9700-16013fd9e8aa X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: NGKym3Um/o0EBboaKIogT2JA5VOgvbbZ608z6pywOrDY0+baKSbMsOm9u57Kau0Ml/3nOrRoVNv2oqE3rVbL5A== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR12MB2710 X-OriginatorOrg: synopsys.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200603_124653_261132_D5D1B9BD X-CRM114-Status: GOOD ( 12.01 ) X-BeenThere: linux-snps-arc@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on Synopsys ARC Processors List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "linux-snps-arc@lists.infradead.org" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-snps-arc" Errors-To: linux-snps-arc-bounces+linux-snps-arc=archiver.kernel.org@lists.infradead.org On 5/29/20 9:49 AM, Adhemerval Zanella via Libc-alpha wrote: >> + ; ----- child starts here --------- >> + >> + ; Setup TP register (only recent kernels v4.19+ do that) >> + and.f 0, r12, CLONE_SETTLS >> + mov.nz r25, r9 > Do you still need to set it since the minimum supported kernel > for ARC is 5.1 ? Right. > It should be safe for internal glibc usage, since for both pthread > and posix_spawn it blocks all signals including SIGCANCEL and SIGXID. > However this is still small race window if this is called directly > with pthread cancellation or g*uid in multithread. I'm not sure what you mean above. Do you mean not doing this in glibc and even if kernel support didn't exist should be safe internally ? fwiw as mentioned above kernel sets up TP for clone (SETTLS). I detested doing that for a long time, give ABI implications but ended up doing it anyways due to an actual race hit when running uClibc tst-kill6 [1] [1] http://lists.infradead.org/pipermail/linux-snps-arc/2018-October/004480.html _______________________________________________ linux-snps-arc mailing list linux-snps-arc@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-snps-arc