From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761449Ab0J1Szv (ORCPT ); Thu, 28 Oct 2010 14:55:51 -0400 Received: from mail3.caviumnetworks.com ([12.108.191.235]:11870 "EHLO mail3.caviumnetworks.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761432Ab0J1Szl (ORCPT ); Thu, 28 Oct 2010 14:55:41 -0400 Message-ID: <4CC9C724.3020004@caviumnetworks.com> Date: Thu, 28 Oct 2010 11:55:32 -0700 From: David Daney User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.12) Gecko/20100907 Fedora/3.0.7-1.fc12 Thunderbird/3.0.7 MIME-Version: 1.0 To: Jason Baron , rth@redhat.com CC: "H. Peter Anvin" , rostedt@goodmis.org, mingo@elte.hu, mathieu.desnoyers@polymtl.ca, tglx@linutronix.de, andi@firstfloor.org, roland@redhat.com, masami.hiramatsu.pt@hitachi.com, fweisbec@gmail.com, avi@redhat.com, davem@davemloft.net, vgoyal@redhat.com, sam@ravnborg.org, tony@bakeyournoodle.com, dsd@laptop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] jump label: disable due to compiler bug References: <2d1b1d5d2b3930e1acb063cefffbcb2faf049854.1288212486.git.jbaron@redhat.com> <20101028141757.GA2875@redhat.com> In-Reply-To: <20101028141757.GA2875@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 28 Oct 2010 18:56:06.0671 (UTC) FILETIME=[C6DB89F0:01CB76D1] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/28/2010 07:17 AM, Jason Baron wrote: > On Wed, Oct 27, 2010 at 03:21:55PM -0700, H. Peter Anvin wrote: >> Could you detail the bug, please? static_cpu_has() also uses asm goto. >> > > It seems that gcc can leave the stack in an inconsistent state. > > I only saw this in the 'jmp' enabled case, I'm not sure if it can occur in the > straight-line code path as well. > Jason, Were you going to file a GCC bug on this issue? Someone should. It would be a shame to have the problem persist due to lack of awareness by the GCC developers. David Daney