From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759489AbZEHPXU (ORCPT ); Fri, 8 May 2009 11:23:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753416AbZEHPXE (ORCPT ); Fri, 8 May 2009 11:23:04 -0400 Received: from gw.goop.org ([64.81.55.164]:34009 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751677AbZEHPXC (ORCPT ); Fri, 8 May 2009 11:23:02 -0400 Message-ID: <4A044E55.20803@goop.org> Date: Fri, 08 May 2009 08:23:01 -0700 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.21 (X11/20090320) MIME-Version: 1.0 To: Jan Beulich CC: Ingo Molnar , the arch/x86 maintainers , Linus Torvalds , Xen-devel , Linux Kernel Mailing List Subject: Re: [Xen-devel] [PATCH 2/5] xen/x86-64: clean up warnings aboutIST-using traps References: <4A032EE0.9030607@goop.org> <4A03F947.76EA.0078.0@novell.com> In-Reply-To: <4A03F947.76EA.0078.0@novell.com> X-Enigmail-Version: 0.95.6 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 Jan Beulich wrote: >> else if (addr == (unsigned long)int3) >> addr = (unsigned long)xen_int3; >> - else >> - WARN_ON(val->ist != 0); >> + else if (addr == (unsigned long)double_fault || >> + addr == (unsigned long)stack_segment) { >> > > I don't think you want to exclude handling stack faults: Ordinary memory > references using rsp or rbp as the base register will cause these instead > of general protection faults when the resulting effective address is non- > canonical. > So even usermode memory accesses? Ew. Well, we can run the trap handler on the normal kernel stack in that case. I'll cook something up. J