From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763968AbXEZUnT (ORCPT ); Sat, 26 May 2007 16:43:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759552AbXEZUnM (ORCPT ); Sat, 26 May 2007 16:43:12 -0400 Received: from terminus.zytor.com ([192.83.249.54]:35368 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755099AbXEZUnM (ORCPT ); Sat, 26 May 2007 16:43:12 -0400 Message-ID: <46589BCD.4040807@zytor.com> Date: Sat, 26 May 2007 13:42:53 -0700 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.0 (X11/20070419) MIME-Version: 1.0 To: Rusty Russell CC: "Eric W. Biederman" , Jeremy Fitzhardinge , Chris Wright , Virtualization Mailing List , Linux Kernel Mailing List Subject: Re: Extending boot protocol & bzImage for paravirt_ops References: <4656FB8F.4090604@goop.org> <1180174691.650.8.camel@localhost.localdomain> In-Reply-To: <1180174691.650.8.camel@localhost.localdomain> X-Enigmail-Version: 0.95.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Rusty Russell wrote: >> >> + Bit 6 (write): KEEP_SEGMENTS >> + Protocol: 2.07+ >> + - if 0, reload the segment registers in the 32bit entry point. >> + - if 1, do not reload the segment registers in the 32bit entry point. >> + Assume that %cs %ds %ss %es are all set to flat segments with >> + a base of 0 (or the equivalent for their environment). > > You also want to skip the cli: perhaps a separate flag for this is > appropriate though. > Do we have *any* environment that enters the 32-bit code with interrupts enabled? I would think that is unsafe no matter how you do it. -hpa