Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760611AbYGAU13 (ORCPT ); Tue, 1 Jul 2008 16:27:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754430AbYGAU1S (ORCPT ); Tue, 1 Jul 2008 16:27:18 -0400 Received: from terminus.zytor.com ([198.137.202.10]:32771 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754027AbYGAU1R (ORCPT ); Tue, 1 Jul 2008 16:27:17 -0400 Message-ID: <486A9257.1050302@zytor.com> Date: Tue, 01 Jul 2008 13:23:51 -0700 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.14 (X11/20080501) MIME-Version: 1.0 To: Sean Young CC: Jeremy Fitzhardinge , Rusty Russell , linux-kernel@vger.kernel.org Subject: Re: Regression: boot failure on AMD Elan TS-5500 References: <20080616121138.GA51097@atlantis.8hz.com> <200806162327.34912.rusty@rustcorp.com.au> <48566C88.6000702@goop.org> <20080616161944.GA53539@atlantis.8hz.com> <20080630214347.GA57988@atlantis.8hz.com> <4869558A.9020907@goop.org> <48695871.8000805@zytor.com> <48695F88.9080905@goop.org> <48696167.6050000@zytor.com> <20080701195942.GA76608@atlantis.8hz.com> In-Reply-To: <20080701195942.GA76608@atlantis.8hz.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1270 Lines: 34 Sean Young wrote: > On Mon, Jun 30, 2008 at 03:42:47PM -0700, H. Peter Anvin wrote: >> Jeremy Fitzhardinge wrote: >>> Maybe it really does require the far jump immediately after setting PE >>> in cr0... >>> >>> Hm, I don't remember this paragraph being in vol 3a, section 8.9.1 >>> before. Is it a recent addition? >>> >>> Random failures can occur if other instructions exist between steps >>> 3 and 4 above. Failures will be readily seen in some situations, >>> such as when instructions that reference memory are inserted between >>> steps 3 and 4 while in system management mode. >>> >> I don't remember that, either. > > Which document are we talking about? > Intel's Software Developer's Manual, volume 3a. > I'm afraid it doesn't work. Maybe I can find something in the AMD Elan > documentation. Would a fence make sense? Not really. In particular, I really don't want to add something that is even remotely likely to break on other platforms, and a fence instruction is relatively recent. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/