From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linutronix.de (146.0.238.70:993) by crypto-ml.lab.linutronix.de with IMAP4-SSL for ; 14 Jun 2018 21:39:23 -0000 Received: from mga07.intel.com ([134.134.136.100]) by Galois.linutronix.de with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1fTVaW-0005Z5-0y for speck@linutronix.de; Thu, 14 Jun 2018 18:59:08 +0200 References: From: Tim Chen Message-ID: <21812a41-b940-1118-18a1-ec5af0381cf5@linux.intel.com> Date: Thu, 14 Jun 2018 09:59:04 -0700 MIME-Version: 1.0 In-Reply-To: Subject: [MODERATED] Encrypted Message Content-Type: multipart/mixed; boundary="wMDwqQLaoFnt9PjgXlTAmYsAPHvZoDLv0"; protected-headers="v1" To: speck@linutronix.de List-ID: This is an OpenPGP/MIME encrypted message (RFC 4880 and 3156) --wMDwqQLaoFnt9PjgXlTAmYsAPHvZoDLv0 Content-Type: text/rfc822-headers; protected-headers="v1" Content-Disposition: inline From: Tim Chen To: speck for Jon Masters Subject: Re: FYI - Reading uncached memory --wMDwqQLaoFnt9PjgXlTAmYsAPHvZoDLv0 Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 06/12/2018 10:29 AM, speck for Jon Masters wrote: > FYI Graz have been able to prove the Intel processors will allow > speculative reads of /explicitly/ UC memory (e.g. marked in MTRR). I > believe they actually use the QPI SAD table to determine what memory is= > speculation safe and what memory has side effects (i.e. if it's HA'able= > memory then it's deemed ok to rampantly speculate from it). >=20 > Just in case anyone thought UC was safe against attacks. >=20 > Jon. >=20 Thanks for forwarding the info. Yes, the internal Intel team is aware of this issue. Tim --wMDwqQLaoFnt9PjgXlTAmYsAPHvZoDLv0--