Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757378AbZKSQIc (ORCPT ); Thu, 19 Nov 2009 11:08:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757295AbZKSQIc (ORCPT ); Thu, 19 Nov 2009 11:08:32 -0500 Received: from www.tglx.de ([62.245.132.106]:41629 "EHLO www.tglx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757077AbZKSQIb (ORCPT ); Thu, 19 Nov 2009 11:08:31 -0500 Date: Thu, 19 Nov 2009 17:06:21 +0100 (CET) From: Thomas Gleixner To: Andrew Haley cc: Ingo Molnar , "H. Peter Anvin" , LKML , Andrew Morton , Heiko Carstens , feng.tang@intel.com, Fr??d??ric Weisbecker , Steven Rostedt , Peter Zijlstra , jakub@redhat.com, gcc@gcc.gnu.org Subject: Re: BUG: GCC-4.4.x changes the function frame on some functions In-Reply-To: <4B0567E0.5080803@redhat.com> Message-ID: References: <20091119072040.GA23579@elte.hu> <4B0567E0.5080803@redhat.com> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 904 Lines: 34 On Thu, 19 Nov 2009, Andrew Haley wrote: > Thomas Gleixner wrote: > > There is no real obvious reason why the edi magic needs to be done > > _before_ > > > > push %ebp > > mov %esp,%ebp > > Sure there is: unless you do the adjustment first %ebp won't be 16-aligned. And why is this not done in 99% of the functions in the kernel, just in this one and some random others ? > We're aligning the stack properly, as per the ABI requirements. Can't > you just fix the tracer? Where is that ABI requirement that push %ebp needs to happen on an aligned stack ? And why is this something GCC did not care about until GCC4.4 ? Thanks, tglx -- 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/