From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754117AbZH3Ut2 (ORCPT ); Sun, 30 Aug 2009 16:49:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754094AbZH3Ut2 (ORCPT ); Sun, 30 Aug 2009 16:49:28 -0400 Received: from terminus.zytor.com ([198.137.202.10]:51831 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754093AbZH3Ut1 (ORCPT ); Sun, 30 Aug 2009 16:49:27 -0400 Message-ID: <4A9AE5B1.80305@zytor.com> Date: Sun, 30 Aug 2009 13:48:49 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1b3pre) Gecko/20090513 Fedora/3.0-2.3.beta2.fc11 Thunderbird/3.0b2 MIME-Version: 1.0 To: Borislav Petkov , mingo@redhat.com, linux-kernel@vger.kernel.org, kjwinchester@gmail.com, tglx@linutronix.de, borislav.petkov@amd.com, linux-tip-commits@vger.kernel.org Subject: Re: [PATCH 3/3] x86, AMD: Disable wrongly set X86_FEATURE_LAHF_LM CPUID bit References: <1251633031-2244-1-git-send-email-petkovbb@gmail.com> <1251633031-2244-3-git-send-email-petkovbb@gmail.com> <4A9AD17A.6060507@zytor.com> <20090830193039.GB22234@liondog.tnic> <4A9ADAC3.3020004@zytor.com> <20090830202926.GC22234@liondog.tnic> In-Reply-To: <20090830202926.GC22234@liondog.tnic> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/30/2009 01:29 PM, Borislav Petkov wrote: > > Ok, what do we want actually? We have rdmsr_safe and rdmsrl_safe where > the last one engineers the 2 u32s into a u64. My gut feeling would opt > for the 2 32bit values instead of one 64bit since they're naturally > returned into %eax:%edx. And in the most cases we need only one of the > values. However, the MSRs themselves are 64bit... Hmmm... > The 2x32 bit interface is the legacy interface. It turned out to be a bad idea, but it's hard to clean up all the users. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.