From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964773AbeALPWF (ORCPT + 1 other); Fri, 12 Jan 2018 10:22:05 -0500 Received: from mail-by2nam01on0089.outbound.protection.outlook.com ([104.47.34.89]:46976 "EHLO NAM01-BY2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933926AbeALPWD (ORCPT ); Fri, 12 Jan 2018 10:22:03 -0500 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=Thomas.Lendacky@amd.com; Subject: Re: [PATCH 5/5] x86/feature: Detect the x86 feature Indirect Branch Prediction Barrier To: "Woodhouse, David" , Borislav Petkov , Ashok Raj Cc: linux-kernel@vger.kernel.org, Thomas Gleixner , Tim Chen , Andy Lutomirski , Linus Torvalds , Greg KH , Dave Hansen , Andrea Arcangeli , Andi Kleen , Arjan Van De Ven , Peter Zijlstra , Dan Williams , Paolo Bonzini , Jun Nakajima , Asit Mallick References: <1515720739-43819-1-git-send-email-ashok.raj@intel.com> <1515720739-43819-6-git-send-email-ashok.raj@intel.com> <20180112123223.us2iygz6twype2sr@pd.tnic> <1515760769.22302.445.camel@amazon.co.uk> From: Tom Lendacky Message-ID: <231ac995-0a8f-c55a-1800-5b71a1719a0f@amd.com> Date: Fri, 12 Jan 2018 09:21:53 -0600 User-Agent: Mozilla/5.0 (Windows NT 10.0; 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Correct. Both 0x48 and 0x49 are tied to the same cpuid bit. AMD has a separate cpuid bit for 0x49 (IBPB) alone. Thanks, Tom >