Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758487AbYGASvq (ORCPT ); Tue, 1 Jul 2008 14:51:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752581AbYGASvj (ORCPT ); Tue, 1 Jul 2008 14:51:39 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:39955 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752392AbYGASvh (ORCPT ); Tue, 1 Jul 2008 14:51:37 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: "H. Peter Anvin" Cc: Jeremy Fitzhardinge , Mike Travis , Christoph Lameter , Linux Kernel Mailing List References: <20080604003018.538497000@polaris-admin.engr.sgi.com> <485AC120.6010202@sgi.com> <485AC5D4.6040302@goop.org> <485ACA8F.10006@sgi.com> <485ACD92.8050109@sgi.com> <485AD138.4010404@goop.org> <485ADA12.5010505@sgi.com> <485ADC73.60009@goop.org> <485BDB04.4090709@sgi.com> <485BE80E.10209@goop.org> <485BF8F5.6010802@goop.org> <485BFFC5.6020404@sgi.com> <486912C4.8070705@sgi.com> <48691556.2080208@zytor.com> <48691E8B.4040605@sgi.com> <48694B3B.3010600@goop.org> <486A61A7.1000902@zytor.com> Date: Tue, 01 Jul 2008 11:41:50 -0700 In-Reply-To: <486A61A7.1000902@zytor.com> (H. Peter Anvin's message of "Tue, 01 Jul 2008 09:56:07 -0700") Message-ID: User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SA-Exim-Connect-IP: 24.130.11.59 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-DCC: XMission; sa01 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ;"H. Peter Anvin" X-Spam-Relay-Country: X-Spam-Report: * -1.8 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.0 T_TM2_M_HEADER_IN_MSG BODY: T_TM2_M_HEADER_IN_MSG * -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% * [score: 0.0000] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa01 1397; Body=1 Fuz1=1 Fuz2=1] * 0.0 XM_SPF_Neutral SPF-Neutral Subject: Re: [crash, bisected] Re: [PATCH 3/4] x86_64: Fold pda into per cpu area X-SA-Exim-Version: 4.2 (built Thu, 03 Mar 2005 10:44:12 +0100) X-SA-Exim-Scanned: Yes (on mgr1.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1096 Lines: 26 "H. Peter Anvin" writes: > Eric W. Biederman wrote: >>> >>> The zero-based PDA mechanism requires the introduction of a new ELF segment >>> based at vaddr 0 which is sufficiently unusual that it wouldn't surprise me > if >>> its triggering some toolchain bug. >> >> Agreed. Given the previous description my hunch is that the bug is occurring >> during objcopy. If vmlinux is good and the compressed kernel is bad. >> > > Actually, it's not all that unusual... it's pretty common in various restricted > environments. That being said, it's probably uncommon for *64-bit* code. It is a sensible thing to expect to work. By unusual I mean it isn't triggered by normal userspace code. In general I find that ld features if they aren't used in userspace and they aren't used in the kernel don't work reliably across versions. Eric -- 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/