From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752024AbaAPELq (ORCPT ); Wed, 15 Jan 2014 23:11:46 -0500 Received: from terminus.zytor.com ([198.137.202.10]:59882 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751632AbaAPELm (ORCPT ); Wed, 15 Jan 2014 23:11:42 -0500 Message-ID: <52D75BE2.1040708@zytor.com> Date: Wed, 15 Jan 2014 20:11:14 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-Version: 1.0 To: Ingo Molnar , "H. Peter Anvin" CC: Borislav Petkov , linux-kernel@vger.kernel.org, aravind.gopalakrishnan@amd.com, tglx@linutronix.de, linux-tip-commits@vger.kernel.org Subject: Re: [tip:x86/urgent] x86, cpu, amd: Add workaround for family 16h, erratum 793 References: <20140114230711.GS29865@pd.tnic> <52D5DC51.9010606@zytor.com> <20140115062817.GA11869@gmail.com> <20140115133619.GA32051@pd.tnic> <52D69291.8080003@linux.intel.com> <20140115183807.GA23486@gmail.com> In-Reply-To: <20140115183807.GA23486@gmail.com> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/15/2014 10:38 AM, Ingo Molnar wrote: > > Right, the fact that most of our MSR accesses today are > crash-on-failure, which happens to trigger crashes on a regular > schedule, where most of the crashes are 'harmless' situation except > that they crash the systems for good. > > So I think defaulting to soft failures is the right approach. > Well, as I said, as long as people don't start doing: BUG_ON(msr_read(...)) ... 'cuz that's just silly. Also, on 64 bits the code generated by going from 2x32 bits to 1x64 and sometimes back can add up (on 32 bits there is no difference.) -hpa