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 7E552C433B4 for ; Wed, 28 Apr 2021 14:48:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3DB576142A for ; Wed, 28 Apr 2021 14:48:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239061AbhD1OtX convert rfc822-to-8bit (ORCPT ); Wed, 28 Apr 2021 10:49:23 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([185.58.86.151]:30264 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238843AbhD1OtW (ORCPT ); Wed, 28 Apr 2021 10:49:22 -0400 Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-213-Q40LSYhmNgio6b75f9Ipug-1; Wed, 28 Apr 2021 15:48:34 +0100 X-MC-Unique: Q40LSYhmNgio6b75f9Ipug-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) by AcuMS.aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 28 Apr 2021 15:48:32 +0100 Received: from AcuMS.Aculab.com ([fe80::994c:f5c2:35d6:9b65]) by AcuMS.aculab.com ([fe80::994c:f5c2:35d6:9b65%12]) with mapi id 15.00.1497.015; Wed, 28 Apr 2021 15:48:32 +0100 From: David Laight To: 'Yu-cheng Yu' , "x86@kernel.org" , "H. Peter Anvin" , Thomas Gleixner , "Ingo Molnar" , "linux-kernel@vger.kernel.org" , "linux-doc@vger.kernel.org" , "linux-mm@kvack.org" , "linux-arch@vger.kernel.org" , "linux-api@vger.kernel.org" , Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , "Eugene Syromiatnikov" , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin , "Weijiang Yang" , Pengfei Xu , "Haitao Huang" Subject: RE: [PATCH v26 0/9] Control-flow Enforcement: Indirect Branch Tracking Thread-Topic: [PATCH v26 0/9] Control-flow Enforcement: Indirect Branch Tracking Thread-Index: AQHXO6ae1Nsozyj+DkCGokhshY0p/arKAkvw Date: Wed, 28 Apr 2021 14:48:32 +0000 Message-ID: <0e03c50ea05440209d620971b9db4f29@AcuMS.aculab.com> References: <20210427204720.25007-1-yu-cheng.yu@intel.com> In-Reply-To: <20210427204720.25007-1-yu-cheng.yu@intel.com> 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 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org From: Yu-cheng Yu > Sent: 27 April 2021 21:47 > > Control-flow Enforcement (CET) is a new Intel processor feature that blocks > return/jump-oriented programming attacks. Details are in "Intel 64 and > IA-32 Architectures Software Developer's Manual" [1]. ... Does this feature require that 'binary blobs' for out of tree drivers be compiled by a version of gcc that adds the ENDBRA instructions? If enabled for userspace, what happens if an old .so is dynamically loaded? Or do all userspace programs and libraries have to have been compiled with the ENDBRA instructions? David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)