From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756430Ab0ERVNg (ORCPT ); Tue, 18 May 2010 17:13:36 -0400 Received: from one.firstfloor.org ([213.235.205.2]:40558 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755929Ab0ERVNf (ORCPT ); Tue, 18 May 2010 17:13:35 -0400 Date: Tue, 18 May 2010 23:13:29 +0200 From: Andi Kleen To: "H. Peter Anvin" Cc: Dan Magenheimer , Peter Zijlstra , Andi Kleen , Arjan van de Ven , Thomas Gleixner , Venkatesh Pallipadi , Ingo Molnar , chris.mason@oracle.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86: Export tsc related information in sysfs Message-ID: <20100518211328.GH22675@basil.fritz.box> References: <20100518112509.GD22675@basil.fritz.box> <1274183935.5605.7726.camel@twins>> <4BF2C30F.6030502@zytor.com> <1274201536.5605.8347.camel@twins> <4BF2C881.60807@zytor.com> <1dc4abc2-6455-4b95-90f6-c86bf56ff39a@default> <4BF2E0A2.6030209@zytor.com> <61e3a205-b578-4972-a65a-b96f779aeeb1@default> <4BF2F9E4.8020808@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4BF2F9E4.8020808@zytor.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > I'm not in favor of emulating rdtsc instructions. I would consider > letting them SIGILL (actually SIGSEGV since RDTSC #GP in userspace) when > the TSC is unavailable, though. I doubt we could ever do that, it would likely break just too much code. Yes the code is already broken likely on some system, but there's a big difference between wrong time and crash. -Andi -- ak@linux.intel.com -- Speaking for myself only.