From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753117AbcBJT1w (ORCPT ); Wed, 10 Feb 2016 14:27:52 -0500 Received: from mga11.intel.com ([192.55.52.93]:4259 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751536AbcBJT1v (ORCPT ); Wed, 10 Feb 2016 14:27:51 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,426,1449561600"; d="scan'208";a="912534849" Date: Wed, 10 Feb 2016 11:27:50 -0800 From: "Luck, Tony" To: Borislav Petkov Cc: Ingo Molnar , Andrew Morton , Andy Lutomirski , Dan Williams , elliott@hpe.com, Brian Gerst , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-nvdimm@ml01.01.org, x86@kernel.org Subject: Re: [PATCH v10 4/4] x86: Create a new synthetic cpu capability for machine check recovery Message-ID: <20160210192749.GA29493@agluck-desk.sc.intel.com> References: <97426a50c5667bb81a28340b820b371d7fadb6fa.1454618190.git.tony.luck@intel.com> <20160207171041.GG5862@pd.tnic> <20160209233857.GA24348@agluck-desk.sc.intel.com> <20160210110603.GE23914@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160210110603.GE23914@pd.tnic> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 10, 2016 at 12:06:03PM +0100, Borislav Petkov wrote: > What about MSR_IA32_PLATFORM_ID or some other MSR or register, for > example? Bits 52:50 give us "information concerning the intended platform for the processor" ... but we don't seem to decode that vague statement into anything that I can make use of. > I.e., isn't there some other, more reliable distinction between E5 and > E7 besides the model ID? Digging in the data sheet I found the CAPID0 register which does indicate in bit 4 whether this is an "EX" (a.k.a. "E7" part). But we invent a new PCI device ID for this every generation (0x0EC3 in Ivy Bridge, 0x2fc0 in Haswell, 0x6fc0 in Broadwell). The offset has stayed at 0x84 through all this. I don't think that hunting the ever-changing PCI-id is a good choice ... the "E5/E7" naming convention has stuck for four generations[1] (Sandy Bridge, Ivy Bridge, Haswell, Broadwell). -Tony [1] Although this probably means that marketing are about to think of something new ... they generally do when people start understanding the model names :-( -Tony