Received: by 2002:ac0:a582:0:0:0:0:0 with SMTP id m2-v6csp1407137imm; Thu, 4 Oct 2018 13:08:23 -0700 (PDT) X-Google-Smtp-Source: ACcGV631itqDO7hXU/9TaAoy0mcFZOE5Vxcz4ltq+urNPTYfxolqiWhCgbYO8K7E689Bj+KCuMG4 X-Received: by 2002:a63:4907:: with SMTP id w7-v6mr7117166pga.123.1538683703585; Thu, 04 Oct 2018 13:08:23 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1538683703; cv=none; d=google.com; s=arc-20160816; b=PcIF+9hR4JXWAq0J0I9mnCTpP/Euy5x08J2DsN4HBV0wFrPvj/DpJLi2U+UEkL48Ov KINA4alnbl8iAAx5MmjPyJQtHyO7Cj4TmYLYC0PZ8vZvfTc6/lYHLKi+q1h+ahxZh6h4 GxcaKlgr5weEC3BeFK/Y624rZGNLREifgmscZ/X5BWUmQ5GnxP+jM07UZuQAuA1qc59J /Q5mcaIAlTUFEnnMWzsrHjTL/Yn7fePlMSW8kC174QqjKAQ6BKSye2pONnyfqIHTz6m4 WhihAN9vJ0F9Wcgm4pz5piCW0Js4M4a5D+8nPwESKRYpXqzzPGuhLAtfA0y7Yc2+4a4k vDkw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:mime-version:content-transfer-encoding :content-id:spamdiagnosticmetadata:spamdiagnosticoutput:bcl :content-language:accept-language:in-reply-to:references:message-id :date:thread-index:thread-topic:subject:cc:to:from:dkim-signature; bh=h/wQ1hFsQodJU7xhZi9WpQtyAUkJ78GBSrcQOZOIy8M=; b=WwSFXNk8c4NTDKJmhZLStHz6wofFVaD439vlqbI2oH3zV/9Zlj9XYgLQcpDvSmu8ZT L/JsZQ4/Bcf2pR/fC0Fug/HhLZipLzPKtnFLujep5dk91ka+QliPycu7tOPMPLc8XmB6 rjyndWHVkFbHA1Nb00dSY6M3jfMBEAjbqqGVv8Ynx7gbSToT0lzEUII/v6wtEBzZUWuj ZWJr2apr+mAMgcuTNtEuvAvsaVIy68zkYeCiaY+FocD5TRWUJHWEkH7cjQ2WQD+icMa9 lntNZTFvIIwGxDnWEqsfuHe5xgzgvhGTx4bwHPb/owPAaLrXf3FFPpWhFr9pWrxG6VPO mJBQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@vmware.com header.s=selector1 header.b=ikji5sV7; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=vmware.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id u129-v6si6205366pfb.247.2018.10.04.13.08.07; Thu, 04 Oct 2018 13:08:23 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@vmware.com header.s=selector1 header.b=ikji5sV7; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=vmware.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727768AbeJEDAt (ORCPT + 99 others); Thu, 4 Oct 2018 23:00:49 -0400 Received: from mail-co1nam03on0065.outbound.protection.outlook.com ([104.47.40.65]:3560 "EHLO NAM03-CO1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727354AbeJEDAs (ORCPT ); Thu, 4 Oct 2018 23:00:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=vmware.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=h/wQ1hFsQodJU7xhZi9WpQtyAUkJ78GBSrcQOZOIy8M=; b=ikji5sV7ZoovO5y+jsz4A6/j6H6FBrf5ape5yeEnNxAljY8M7VDiSqpYLYjb4Ene/9SoHCuugLalVg+oC4wQbEfZig+GTVwIGdGgoRoO1sSLA3qWfwFs1cgcNHJm8BB+a1Ll5cTO+gwhCpt8+uZKZ3j46yG/1WZdn36Tas3fJbQ= Received: from BYAPR05MB4776.namprd05.prod.outlook.com (52.135.233.146) by BYAPR05MB4232.namprd05.prod.outlook.com (52.135.200.155) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1207.13; Thu, 4 Oct 2018 20:05:55 +0000 Received: from BYAPR05MB4776.namprd05.prod.outlook.com ([fe80::49cd:7d04:35b7:b2a2]) by BYAPR05MB4776.namprd05.prod.outlook.com ([fe80::49cd:7d04:35b7:b2a2%3]) with mapi id 15.20.1207.018; Thu, 4 Oct 2018 20:05:55 +0000 From: Nadav Amit To: "H. Peter Anvin" , Ingo Molnar CC: Ingo Molnar , "linux-kernel@vger.kernel.org" , "x86@kernel.org" , Thomas Gleixner , Jan Beulich , Josh Poimboeuf , Linus Torvalds , Peter Zijlstra , Andy Lutomirski Subject: Re: [PATCH v9 04/10] x86: refcount: prevent gcc distortions Thread-Topic: [PATCH v9 04/10] x86: refcount: prevent gcc distortions Thread-Index: AQHUW2CZEG0GJCpfDkK4fEgcOSwgMqUOuSmAgAAJ9ICAAAHlAIAABIuAgAABwICAAAPpgIAArDAAgAAJJgA= Date: Thu, 4 Oct 2018 20:05:55 +0000 Message-ID: References: <20181003213100.189959-1-namit@vmware.com> <20181003213100.189959-5-namit@vmware.com> <20181004075755.GA3353@gmail.com> <20181004083333.GA9802@gmail.com> <10D29A50-C352-4407-A824-0C3C06CD8592@zytor.com> <36D6F606-6922-4057-B1F8-2B30993962AE@zytor.com> <20181004091651.GB21151@gmail.com> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: spf=none (sender IP is ) smtp.mailfrom=namit@vmware.com; x-originating-ip: [66.170.99.1] x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1;BYAPR05MB4232;20:bSuxxN3tV7tdkkFq9VaupQt8hnT/gK1SjiWy/1+3VFVUUzNoY25hPbyVA9moWd+a7NieJjasIyQnbjHR+LUBHZJigkF8iGpJ2OdB0m3Zzx9B2jnh6BleIDynp6mzvNFCoYxCe9s2XwmAFtBQWJPDNZajntURYuNqKN0OXnrXJnU= x-ms-exchange-antispam-srfa-diagnostics: SOS; x-ms-office365-filtering-correlation-id: 2fc760b2-e0a4-4823-4d1e-08d62a34cb43 x-microsoft-antispam: BCL:0;PCL:0;RULEID:(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600074)(711020)(2017052603328)(7153060)(7193020);SRVR:BYAPR05MB4232; x-ms-traffictypediagnostic: BYAPR05MB4232: bcl: 0 x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:(219752817060721)(189930954265078); x-ms-exchange-senderadcheck: 1 x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(8211001083)(6040522)(2401047)(8121501046)(5005006)(3231355)(944501410)(4982022)(52105095)(10201501046)(93006095)(93001095)(3002001)(149066)(150057)(6041310)(20161123562045)(20161123558120)(20161123564045)(20161123560045)(201703131423095)(201702281528075)(20161123555045)(201703061421075)(201703061406153)(201708071742011)(7699051);SRVR:BYAPR05MB4232;BCL:0;PCL:0;RULEID:;SRVR:BYAPR05MB4232; x-forefront-prvs: 0815F8251E x-forefront-antispam-report: SFV:NSPM;SFS:(10009020)(136003)(39860400002)(396003)(376002)(366004)(346002)(54534003)(199004)(189003)(6246003)(86362001)(6306002)(25786009)(54906003)(6512007)(5250100002)(82746002)(6486002)(229853002)(4326008)(6436002)(5660300001)(2900100001)(53936002)(106356001)(105586002)(45080400002)(66066001)(6116002)(186003)(26005)(476003)(316002)(68736007)(2906002)(81166006)(7416002)(81156014)(102836004)(7736002)(6506007)(36756003)(478600001)(3846002)(8936002)(76176011)(305945005)(99286004)(8676002)(93886005)(14444005)(11346002)(966005)(256004)(14454004)(97736004)(53546011)(71190400001)(71200400001)(110136005)(486006)(446003)(83716004)(33656002)(2616005);DIR:OUT;SFP:1101;SCL:1;SRVR:BYAPR05MB4232;H:BYAPR05MB4776.namprd05.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;A:1;MX:1; received-spf: None (protection.outlook.com: vmware.com does not designate permitted sender hosts) x-microsoft-antispam-message-info: /3v+VftDGoYnIgYhENPJMArUgblMOkb0kvt11HuFX5LEylm7H9hAa5hQOixNDK8OUIaVKjUcrdoBpOgfqbSKaVQRP2HejxpeYcizb8TewfanuGE9juiPl3JQzBGkJu/LJNX1BhNWtFBAg19dZ0cRv+6XebN0fsjgy6J4JqWCCJmqV7rJIPRCyU0LLt7wVhmCPk2Va8NT2nzYWsXFBtp2G9M4bLFSvk0iho5iwOKZZfXb8JauM5/SYhgEOB8S9TvxEWdP1BYL9YeOIpxxCd7kKAWnUmSaq7HzD5tEjUpMK/ib+AoQEHvpFcGZB4gjY4m/1B7mXTrT4DRorDcXB5dgmKXKyKRqqlAeIUXOC6d1tVg= spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="utf-8" Content-ID: <1BFCC0E8FC8AC74581FEE822669CB8B3@namprd05.prod.outlook.com> Content-Transfer-Encoding: base64 MIME-Version: 1.0 X-OriginatorOrg: vmware.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2fc760b2-e0a4-4823-4d1e-08d62a34cb43 X-MS-Exchange-CrossTenant-originalarrivaltime: 04 Oct 2018 20:05:55.4324 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: b39138ca-3cee-4b4a-a4d6-cd83d9dd62f0 X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR05MB4232 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org YXQgMTI6MzMgUE0sIEguIFBldGVyIEFudmluIDxocGFAenl0b3IuY29tPiB3cm90ZToNCg0KPiBP biAxMC8wNC8xOCAwMjoxNiwgSW5nbyBNb2xuYXIgd3JvdGU6DQo+PiAqIGhwYUB6eXRvci5jb20g PGhwYUB6eXRvci5jb20+IHdyb3RlOg0KPj4gDQo+Pj4gSW5nbzogSSB3YXNuJ3QgdGFsa2luZyBu ZWNlc3NhcmlseSBhYm91dCB0aGUgc3BlY2lmaWNzIG9mIGVhY2ggYml0LCBidXQgcmF0aGVyIHRo ZSBnZW5lcmFsIA0KPj4+IGNvbmNlcHQgYWJvdXQgYmVpbmcgYWJsZSB0byB1c2UgbWFjcm9zIGlu IGlubGluZXMuLi4NCj4+IA0KPj4gT2ssIGFncmVlZCBhYm91dCB0aGF0IHBhcnQgLSBhbmQgc29t ZSBvZiB0aGUgcGF0Y2hlcyBkaWQgaW1wcm92ZSByZWFkYWJpbGl0eS4NCj4+IA0KPj4gQWxzbywg dGhlIDI3NSBsaW5lcyBtYWNyb3MucyBpcyBhIGxvdCBuaWNlciB0aGFuIHRoZSA0LDIwMCBsaW5l cyBtYWNyb3MuUy4NCj4+IA0KPj4gQWxzbywgSSdtIG5vdCBhZ2FpbnN0IHVzaW5nIHdvcmthcm91 bmRzIHdoZW4gdGhlIGJlbmVmaXRzIGFyZSBsYXJnZXIgdGhhbiB0aGUgY29zdHMsIGJ1dCBJIGFt IA0KPj4gYWdhaW5zdCAqaGlkaW5nKiB0aGUgZmFjdCB0aGF0IHRoZXNlIGFyZSB3b3JrYXJvdW5k cyBhbmQgdGhhdCBmb3Igc29tZSBvZiB0aGVtIHRoZXJlIGFyZSBjb3N0cy4NCj4gDQo+IEFncmVl ZCwgb2YgY291cnNlLg0KPiANCj4+PiBJIGNhbiBzZW5kIHlvdSBzb21ldGhpbmcgSSBoYXZlIGJl ZW4gd29ya2luZyBvbiBpbiB0aGUgYmFja2dyb3VuZCwgYnV0IGhhdmUgYmVlbiBob2xkaW5nIG9m ZiANCj4+PiBvbiBiZWNhdXNlIG9mIHRoaXMsIGluIHRoZSBtb3JuaW5nIG15IHRpbWUuDQo+PiAN Cj4+IEJUVy4sIEkgaGF2ZSBhcHBsaWVkIG1vc3Qgb2YgdGhlIHNlcmllcyB0byB0aXA6eDg2L2ti dWlsZCBhbHJlYWR5LCBhbmQgd2lsbCBwdXNoIHRoZW0gb3V0IGxhdGVyIA0KPj4gdG9kYXkgYWZ0 ZXIgc29tZSB0ZXN0aW5nLiBJIGRpZG4ndCBhcHBseSB0aGUgZmluYWwgMyBwYXRjaGVzIGFzIHRo ZXkgaGF2ZSBkZXBlbmRlbmNpZXMsIGJ1dCANCj4+IGFwcGxpZWQgdGhlIGJhc2ljcyBhbmQgZml4 ZWQgdXAgdGhlIGNoYW5nZWxvZ3MuDQo+PiANCj4+IFNvIHlvdSBjYW4gcmVseSBvbiB0aGlzLg0K PiANCj4gV29uZGVyZnVsLg0KPiANCj4gSGVyZSBpcyB0aGUgaG9ycmlibGUgY29kZSBJIG1lbnRp b25lZCB5ZXN0ZXJkYXkuICBUaGlzIGlzIGFib3V0DQo+IGltcGxlbWVudGluZyB0aGUgaW1tZWRp YXRlLXBhdGNoaW5nIGZyYW1ld29yayB0aGF0IExpbnVzIGFuZCBvdGhlcnMgaGF2ZQ0KPiBkaXNj dXNzZWQgKGl0IGhlbHBzIGJvdGggcGVyZm9ybWFuY2UgYW5kIGtlcm5lbCBoYXJkZW5pbmcpOg0K PiANCj4gV2FybmluZzogdGhpcyBzdHVmZiBjYW4gY2F1c2Ugc2VyaW91cyBkYW1hZ2UgdG8geW91 ciBleWVzLCBhbmQgdGhpcyBpcyBhDQo+IGp1c3QgYSBzbWFsbCBjaHVuayBvZiB0aGUgd2hvbGUg bWVzczsgYW5kIHJlbHlpbmcgb24gZ2FzIG1hY3JvcywgYXMNCj4gYnJhaW4gZGFtYWdlZCBhcyB0 aGV5IGFyZSwgcmVhbGx5IGlzIG11Y2gsIG11Y2ggY2xlYW5lciB0aGFuIG5vdDoNCj4gDQo+IAlo dHRwczovL25hMDEuc2FmZWxpbmtzLnByb3RlY3Rpb24ub3V0bG9vay5jb20vP3VybD1odHRwOiUy RiUyRnd3dy56eXRvci5jb20lMkZ+aHBhJTJGZm9vLlMmYW1wO2RhdGE9MDIlN0MwMSU3Q25hbWl0 JTQwdm13YXJlLmNvbSU3QzMyNmYxYTNiZWI0NjQ5ZGYzMTk1MDhkNjJhMzA0MmZhJTdDYjM5MTM4 Y2EzY2VlNGI0YWE0ZDZjZDgzZDlkZDYyZjAlN0MxJTdDMCU3QzYzNjc0Mjc4NDExMTY3MTEyMiZh bXA7c2RhdGE9YW5ZSU9YemxTVFhQUUt0dFRCSGpTUWdhcEJtYU85Z2ZpYkJGMzRabEhlUSUzRCZh bXA7cmVzZXJ2ZWQ9MA0KDQpGdW5ueS4gSW1tZWRpYXRlLXBhdGNoaW5nIGlzIHdoYXQgSSB3YXMg cGxheWluZyB3aXRoIHdoZW4gSSBlbmNvdW50ZXJlZCB0aGUNCmdjYyBpc3N1ZS4gUGVyZm9ybWFu Y2UgZ290IHdvcnNlIGluc3RlYWQgb2YgaW1wcm92aW5nIChvciBhdCBsZWFzdCBzdGF5aW5nDQp0 aGUgc2FtZSksIGJlY2F1c2UgaW5saW5pbmcgZ290IGNyYXp5Lg0KDQpBbnlob3csIHdhaXQgZm9y IG15IHNvb24tdG8tYmUtc2VudCBSRkMgaW4gd2hpY2ggSSBkZWZpbmUgYSBtYWNybyBjYWxsZWQN CuKAnGNhbGzigJ0gKHRvIHJlZHVjZSB0aGUgcmV0cG9saW5lIG92ZXJoZWFkKSBiZWZvcmUgeW91 IHRhbGsgYWJvdXQgZGFtYWdlIHRvDQp0aGUgZXllcy4NCg0K