From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752398Ab0APVKU (ORCPT ); Sat, 16 Jan 2010 16:10:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752262Ab0APVKS (ORCPT ); Sat, 16 Jan 2010 16:10:18 -0500 Received: from terminus.zytor.com ([198.137.202.10]:39367 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751870Ab0APVKQ (ORCPT ); Sat, 16 Jan 2010 16:10:16 -0500 Message-ID: <4B522B23.5090903@zytor.com> Date: Sat, 16 Jan 2010 13:09:55 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.5) Gecko/20091209 Fedora/3.0-3.fc11 Thunderbird/3.0 MIME-Version: 1.0 To: Linus Torvalds CC: Ingo Molnar , linux-kernel@vger.kernel.org, Thomas Gleixner , Andrew Morton Subject: Re: [GIT PULL] x86 fixes References: <20100116170338.GA17175@elte.hu> <4B522A61.2010504@zytor.com> In-Reply-To: <4B522A61.2010504@zytor.com> 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 01/16/2010 01:06 PM, H. Peter Anvin wrote: > On 01/16/2010 12:34 PM, Linus Torvalds wrote: >> >> >> On Sat, 16 Jan 2010, Ingo Molnar wrote: >>> >>> Cyrill Gorcunov (1): >>> x86: kernel_thread() -- initialize SS to a known state >> >> This looks bogus. Why does it do it only on x86-64? >> >> Either people care about SS or they don't (the answer, I suspect, is "they >> don't"). But if they care, we should do it on both 32-bit _and_ 64-bit, >> no? >> > > It is bogus -- it's basically Xen braindamage. > As to why make it x86-64 only... it matches what the old assembly code did. We figured that that was the lowest risk option for unbreaking Xen. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.