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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-kernel@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)