From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755123AbZBJNys (ORCPT ); Tue, 10 Feb 2009 08:54:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753225AbZBJNyk (ORCPT ); Tue, 10 Feb 2009 08:54:40 -0500 Received: from hera.kernel.org ([140.211.167.34]:47688 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751920AbZBJNyj (ORCPT ); Tue, 10 Feb 2009 08:54:39 -0500 Message-ID: <499186FB.4070506@kernel.org> Date: Tue, 10 Feb 2009 22:54:03 +0900 From: Tejun Heo User-Agent: Thunderbird 2.0.0.19 (X11/20081227) MIME-Version: 1.0 To: Ingo Molnar CC: hpa@zytor.com, jeremy@goop.org, tglx@linutronix.de, linux-kernel@vger.kernel.org, x86@kernel.org, rusty@rustcorp.com.au Subject: Re: [PATCHSET x86/master] add stack protector support for x86_32 References: <1234186798-16820-1-git-send-email-tj@kernel.org> <20090209135557.GB14785@elte.hu> <20090209141209.GA24323@elte.hu> In-Reply-To: <20090209141209.GA24323@elte.hu> X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Tue, 10 Feb 2009 13:54:16 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ingo Molnar wrote: > * Ingo Molnar wrote: > >> [...] I might not get around testing it today and pushing it out into tip:master, >> but i pushed out the core/percpu bits, should you queue up further changes. > > ok, activated it for -tip testing, and there's a 64-bit build failure caused by > it: > > arch/x86/kernel/head64.o: In function `x86_64_start_reservations': > head64.c:(.init.text+0x26): undefined reference to `__stack_chk_guard' > head64.c:(.init.text+0xc2): undefined reference to `__stack_chk_guard' > arch/x86/kernel/head64.o: In function `x86_64_start_kernel': > head64.c:(.init.text+0x104): undefined reference to `__stack_chk_guard' > head64.c:(.init.text+0x1cd): undefined reference to `__stack_chk_guard' > arch/x86/kernel/head.o: In function `reserve_ebda_region': > head.c:(.init.text+0xb): undefined reference to `__stack_chk_guard' > arch/x86/kernel/head.o:head.c:(.init.text+0x87): more undefined references to > `__stack_chk_guard' follow Call to __stack_chk_guard is probably generated automatically. Strangely, my gcc only generates calls to __stack_chk_fail. > gcc --version gcc (SUSE Linux) 4.3.2 [gcc-4_3-branch revision 141291] Copyright (C) 2008 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. > nm build/vmlinux|grep __stack_chk_ 00000000f0fdf6cb A __crc___stack_chk_fail ffffffff80d53e50 r __kcrctab___stack_chk_fail ffffffff80d5ff81 r __kstrtab___stack_chk_fail ffffffff80d3d140 r __ksymtab___stack_chk_fail ffffffff80248619 T __stack_chk_fail I'll try other compilers but which version are you using? The difference is that before the patchset, -fno-stack-protector was always added whether stackprotector was enabled or not so this problem wasn't visible (at the cost of bogus stackprotector of course). We'll probably need to add __stack_chk_guard or disable if gcc generates such symbol. I'll play with different gccs. Thanks. -- tejun