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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 3C1ACC43461 for ; Wed, 9 Sep 2020 08:20:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 057FA208FE for ; Wed, 9 Sep 2020 08:20:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729298AbgIIIUP (ORCPT ); Wed, 9 Sep 2020 04:20:15 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([185.58.86.151]:27351 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726111AbgIIIUO (ORCPT ); Wed, 9 Sep 2020 04:20:14 -0400 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-161-BdXcDBudNH26BNJoUCbwvw-1; Wed, 09 Sep 2020 09:20:08 +0100 X-MC-Unique: BdXcDBudNH26BNJoUCbwvw-1 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; Wed, 9 Sep 2020 09:20:07 +0100 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; Wed, 9 Sep 2020 09:20:07 +0100 From: David Laight To: 'Josh Poimboeuf' , "x86@kernel.org" CC: "linux-kernel@vger.kernel.org" , "Linus Torvalds" , Al Viro , Will Deacon , Dan Williams , Andrea Arcangeli , Waiman Long , Peter Zijlstra , Thomas Gleixner , Andrew Cooper , Andy Lutomirski , Christoph Hellwig , Mark Rutland Subject: RE: [PATCH v2] x86/uaccess: Use pointer masking to limit uaccess speculation Thread-Topic: [PATCH v2] x86/uaccess: Use pointer masking to limit uaccess speculation Thread-Index: AQHWhgeZBzEzlDBqrkarsC8PutwJjalf9DHA Date: Wed, 9 Sep 2020 08:20:07 +0000 Message-ID: <01b027d0d46d4572b3b16e2b49f0f2b3@AcuMS.aculab.com> References: <20200908174329.ryfprry62e4tuodw@treble> In-Reply-To: <20200908174329.ryfprry62e4tuodw@treble> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0.001 X-Mimecast-Originator: aculab.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: base64 Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org RnJvbTogSm9zaCBQb2ltYm9ldWYgPGpwb2ltYm9lQHJlZGhhdC5jb20+DQo+IFNlbnQ6IDA4IFNl cHRlbWJlciAyMDIwIDE4OjQzDQo+IEhpIHg4NiBtYWludGFpbmVycywNCi4uLg0KPiA+IC0tLSBh L2FyY2gveDg2L2xpYi9wdXR1c2VyLlMNCj4gPiArKysgYi9hcmNoL3g4Ni9saWIvcHV0dXNlci5T DQo+ID4gQEAgLTM4LDYgKzM4LDggQEAgU1lNX0ZVTkNfU1RBUlQoX19wdXRfdXNlcl8xKQ0KPiA+ ICAJRU5URVINCj4gPiAgCWNtcCBUQVNLX2FkZHJfbGltaXQoJV9BU01fQlgpLCVfQVNNX0NYDQo+ ID4gIAlqYWUgLkxiYWRfcHV0X3VzZXINCj4gPiArCXNiYiAlX0FTTV9CWCwgJV9BU01fQlgJCS8q IHVhY2Nlc3NfbWFza19wdHIoKSAqLw0KPiA+ICsJYW5kICVfQVNNX0JYLCAlX0FTTV9DWA0KPiA+ ICAJQVNNX1NUQUMNCj4gPiAgMToJbW92YiAlYWwsKCVfQVNNX0NYKQ0KPiA+ICAJeG9yICVlYXgs JWVheA0KDQpGb3IgNjRiaXQgdGhlIHNiYithbmQgcGF0dGVybiBjYW4gYmUgcmVwbGFjZWQgYnkg YW4gaW5zdHJ1Y3Rpb24NCnRoYXQgY2xlYXJzIHRoZSBoaWdoIGJpdCAoZWcgYnRyICQ2MywgJXJj eCkuDQpUaGlzIGlzbid0IGRlcGVuZGFudCBvbiB0aGUgZWFybGllciBpbnN0cnVjdGlvbnMgc28g Y2FuIGV4ZWN1dGUNCmluIHBhcmFsbGVsIHdpdGggdGhlbS4NCg0KSSBzdGlsbCB0aGluayB0aGF0 IGRvaW5nIHRoZSBzYW1lIGNvbXBhcmlzb25zIGluIGFjY2Vzc19vaygpDQphbmQgZm9yIHRoZSBw b2ludGVyIG1hc2tpbmcgaXMgc2lsbHkgLSBhbmQgdGhleSBzaG91bGQgZ2V0IG1lcmdlZC4NCg0K V2hpbGUgaXQgbWF5IGJlIHBvc3NpYmxlIHRvIGZha2UgJ2FzbSB2b2xhdGlsZSBnb3RvIHdpdGgg b3V0cHV0cycNCmJ5IHVzaW5nIGEgbG9jYWwgYXNtIHJlZ2lzdGVyIHZhcmlhYmxlIGFuZCBhbHRl cm5hdGl2ZSBwYXR0ZXJuDQptaWdodCBiZSB0byBoYXZlIGFjY2Vzc19vaygpIHJldHVybiAwIChm YWlsKSBvciB+MCAob2spLg0KVGhlbiB0aGUgdXNhZ2UgY2FuIGJlICh3aXRoIGEgbG9hZCBvZiBj YXN0cyk6DQoJcDEgPSBwICYgYWNjZXNzX29rKHApOw0KCWlmICghcDEgJiYgcCkNCgkJcmV0dXJu IC1FRkFVTFQ7DQoJZm9vKCpwMSk7DQpXaXRoIGFueSBsdWNrIHRoZSBjb21waWxlciB3aWxsIHVz ZSB0aGUgcmVzdWx0IG9mIHRoZSAmIGZvciB0aGUNCiFwMSB0ZXN0Lg0KDQoJRGF2aWQNCg0KCQ0K DQotDQpSZWdpc3RlcmVkIEFkZHJlc3MgTGFrZXNpZGUsIEJyYW1sZXkgUm9hZCwgTW91bnQgRmFy bSwgTWlsdG9uIEtleW5lcywgTUsxIDFQVCwgVUsNClJlZ2lzdHJhdGlvbiBObzogMTM5NzM4NiAo V2FsZXMpDQo=