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[209.132.180.67]) by mx.google.com with ESMTP id b12si2845579pga.371.2018.01.26.03.17.29; Fri, 26 Jan 2018 03:17:43 -0800 (PST) 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; 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 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751498AbeAZLQ6 (ORCPT + 99 others); Fri, 26 Jan 2018 06:16:58 -0500 Received: from smtp-out4.electric.net ([192.162.216.194]:63307 "EHLO smtp-out4.electric.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750819AbeAZLQ4 (ORCPT ); Fri, 26 Jan 2018 06:16:56 -0500 Received: from 1ef1zq-0005UL-Vl by out4a.electric.net with emc1-ok (Exim 4.87) (envelope-from ) id 1ef202-0006Z5-Ue; Fri, 26 Jan 2018 03:16:50 -0800 Received: by emcmailer; Fri, 26 Jan 2018 03:16:50 -0800 Received: from [156.67.243.126] (helo=AcuMS.aculab.com) by out4a.electric.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-SHA384:256) (Exim 4.87) (envelope-from ) id 1ef1zq-0005UL-Vl; Fri, 26 Jan 2018 03:16:38 -0800 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Fri, 26 Jan 2018 11:17:29 +0000 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Fri, 26 Jan 2018 11:17:29 +0000 From: David Laight To: 'Andy Lutomirski' , Linus Torvalds CC: the arch/x86 maintainers , LKML , Greg Kroah-Hartman , Alan Cox , Jann Horn , Samuel Neves , Dan Williams , Kernel Hardening , Borislav Petkov Subject: RE: [PATCH] x86/retpoline/entry: Disable the entire SYSCALL64 fast path with retpolines on Thread-Topic: [PATCH] x86/retpoline/entry: Disable the entire SYSCALL64 fast path with retpolines on Thread-Index: AQHTliQLiwNLQ1OW00eC2UTYOOjDo6OF/9fA Date: Fri, 26 Jan 2018 11:17:29 +0000 Message-ID: References: <503224b776b9513885453756e44bab235221124e.1516644136.git.luto@kernel.org> In-Reply-To: Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.33] Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 MIME-Version: 1.0 X-Outbound-IP: 156.67.243.126 X-Env-From: David.Laight@ACULAB.COM X-Proto: esmtps X-Revdns: X-HELO: AcuMS.aculab.com X-TLS: TLSv1.2:ECDHE-RSA-AES256-SHA384:256 X-Authenticated_ID: X-PolicySMART: 3396946, 3397078 X-Virus-Status: Scanned by VirusSMART (c) X-Virus-Status: Scanned by VirusSMART (s) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org RnJvbTogQW5keSBMdXRvbWlyc2tpDQo+IFNlbnQ6IDI1IEphbnVhcnkgMjAxOCAyMTozMQ0KLi4u DQo+IEFub3RoZXIgcG90ZW50aWFsbHkgdXNlZnVsIGlmIHJhdGhlciBtaW5vciBvcHRpbWl6YXRp b24gd291bGQgYmUgdG8NCj4gcmVqaWdnZXIgdGhlIFNZU0NBTExfREVGSU5FIG1hY3JvcyBhIGJp dC4gIEN1cnJlbnRseSB3ZSB0cmVhdCBhbGwNCj4gc3lzY2FsbHMgbGlrZSB0aGlzOg0KPiANCj4g bG9uZyBmdW5jKGxvbmcgYXJnMCwgbG9uZyBhcmcxLCBsb25nIGFyZzIsIGxvbmcgYXJnMywgbG9u ZyBhcmc0LCBsb25nIGFyZzUpOw0KPiANCj4gSSB3b25kZXIgaWYgd2UnZCBiZSBiZXR0ZXIgb2Zm IGRvaW5nOg0KPiANCj4gbG9uZyBmdW5jKGNvbnN0IHN0cnVjdCBwdF9yZWdzICpyZWdzKTsNCj4g DQo+IGFuZCBhdXRvZ2VuZXJhdGluZzoNCj4gDQo+IHN0YXRpYyBsb25nIFN5U19yZWFkKGNvbnN0 IHN0cnVjdCBwdF9yZWdzICpyZWdzKQ0KPiB7DQo+ICAgIHJldHVybiBzeXNfcmVnKHJlZ3MtPmRp LCAuLi4pOw0KPiB9DQoNCkhtbW0uLi4uDQpOZXRCU0QgKGFuZCB0aGUgb3RoZXIgQlNEPykgZGVm aW5lcyBhIHN0cnVjdHVyZSBmb3IgdGhlIGFyZ3VtZW50cyB0byBlYWNoIHN5c2NhbGwuDQpPbiBz eXN0ZW1zIHdoZXJlIGFsbCBmdW5jdGlvbiBhcmd1bWVudHMgYXJlIHB1dCBvbiBzdGFjayB0aGUg dXNlciBzdGFjayB0aGF0DQpjb250YWlucyB0aGUgYXJndW1lbnRzIGlzIGNvcGllZCBpbnRvIGEg a2VybmVsIGJ1ZmZlci4NCkZvciBhbWQ2NCBJIGNoYW5nZWQgdGhlIHJlZ2lzdGVyIHNhdmUgYXJl YSBsYXlvdXQgc28gdGhhdCB0aGUgYXJndW1lbnRzIHdlcmUgaW4NCnRoZSByaWdodCBvcmRlciBb MV0uIFRoZW4gYWRkZWQgYW4gZXh0cmEgYXJlYSBmb3IgdGhlIGV4dHJhIGFyZ3VtZW50cyB0aGF0 IGhhZCB0byBiZQ0KcmVhZCBmcm9tIHRoZSB1c2VyIHN0YWNrLg0KSnVzdCBwYXNzaW5nIGEgcG9p bnRlciBpbnRvIHRoZSBzYXZlIGFyZWEgaGFzIHRvIGJlIGJldHRlciB0aGFuIHJlYWRpbmcNCmFs bCB0aGUgdmFsdWVzIGFnYWluLg0KDQpbMV0gVGhlcmUgd2FzIHNvbWUgaG9ycmlkIGZhbGxvdXQg ZnJvbSB0aGF0IDotKA0KDQoJRGF2aWQNCg0K