From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 67B65C3A59F for ; Thu, 29 Aug 2019 14:33:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3F49523426 for ; Thu, 29 Aug 2019 14:33:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727815AbfH2OdU (ORCPT ); Thu, 29 Aug 2019 10:33:20 -0400 Received: from mx0a-002e3701.pphosted.com ([148.163.147.86]:18328 "EHLO mx0a-002e3701.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726739AbfH2OdT (ORCPT ); Thu, 29 Aug 2019 10:33:19 -0400 Received: from pps.filterd (m0134421.ppops.net [127.0.0.1]) by mx0b-002e3701.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id x7TEQnDw028837; Thu, 29 Aug 2019 14:33:07 GMT Received: from g2t2353.austin.hpe.com (g2t2353.austin.hpe.com [15.233.44.26]) by mx0b-002e3701.pphosted.com with ESMTP id 2upduehe61-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 29 Aug 2019 14:33:07 +0000 Received: from g2t2360.austin.hpecorp.net (g2t2360.austin.hpecorp.net [16.196.225.135]) by g2t2353.austin.hpe.com (Postfix) with ESMTP id 994DA8C; Thu, 29 Aug 2019 14:33:06 +0000 (UTC) Received: from swahl-linux (swahl-linux.americas.hpqcorp.net [10.33.153.21]) by g2t2360.austin.hpecorp.net (Postfix) with ESMTP id 1A59646; Thu, 29 Aug 2019 14:33:06 +0000 (UTC) Date: Thu, 29 Aug 2019 09:33:05 -0500 From: Steve Wahl To: Nick Desaulniers Cc: Steve Wahl , Thomas Gleixner , LKML , russ.anderson@hpe.com, dimitri.sivanich@hpe.com, mike.travis@hpe.com Subject: Re: Purgatory compile flag changes apparently causing Kexec relocation overflows Message-ID: <20190829143305.GD29967@swahl-linux> References: <20190828194226.GA29967@swahl-linux> <20190828221048.GB29967@swahl-linux> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.1 (2019-06-15) X-HPE-SCL: -1 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.70,1.0.8 definitions=2019-08-29_06:2019-08-29,2019-08-29 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 mlxlogscore=674 malwarescore=0 clxscore=1015 bulkscore=0 priorityscore=1501 phishscore=0 lowpriorityscore=0 adultscore=0 impostorscore=0 mlxscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1906280000 definitions=main-1908290158 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 28, 2019 at 03:22:13PM -0700, Nick Desaulniers wrote: > > One point that might be more useful first would be, is a revert of: > > commit b059f801a937 ("x86/purgatory: Use CFLAGS_REMOVE rather than > reset KBUILD_CFLAGS") > > good enough, or must: > > commit 4ce97317f41d ("x86/purgatory: Do not use __builtin_memcpy and > __builtin_memset") > > be reverted additionally? They were part of a 2 patch patchset. I > would prefer tglx to revert as few patches as necessary if possible > (to avoid "revert of revert" soup), and I doubt the latter patch needs > to be reverted. (Even more preferential would be a fix, with no > reverts, but whichever). A revert of the single commit is sufficient. Previously I have checked out and compiled the tree at commit b059f801a937 and b059f801a937^ (with caret, the previous commit). It worked with the previous commit, but not with b059f801a937. 4ce97317f41d *is* the previous commit to b059f801a937, so it was in both kernels that I tested: $ git log -1 --oneline b059f801a937^ | cat 4ce97317f41d x86/purgatory: Do not use __builtin_memcpy and __builtin_memset $ And, I also did an exploratory 'git revert b059f801a937' at the tip of the tree. That corrects the problem as well. So both say that it's only the single commit that would need to be reverted *if* that's the route taken. Now, on to seeing if we can narrow this down to a fix with no reverts instead. --> Steve -- Steve Wahl, Hewlett Packard Enterprise