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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46B95C433F5 for ; Thu, 9 Dec 2021 11:16:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236480AbhLILTk (ORCPT ); Thu, 9 Dec 2021 06:19:40 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:24932 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S236469AbhLILTk (ORCPT ); Thu, 9 Dec 2021 06:19:40 -0500 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 1B99wbjw012697 for ; Thu, 9 Dec 2021 11:16:06 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=pp1; bh=7U6q848gWzDgyibAnUVFRqgT3L4UugWabdVD/3E4JZU=; b=VWFraN0qOC/bD5bSPGSt/08Ha4U7k3DSAx1D+uprI1qO3rNya6o5pg2TNW7+r43AQ9nc ETYUopHtzU9FvgiMn+Zrbty13fJaE26Nl1GGdHyvahb5LaaQ32rBm7GyJUrNsvsqHwtw k5ycP+Q5GtSjjyIqJK1k2WKXmsRAQgztVd5UdtqgowGaYDZob3BwQ0zm3Ftym2PeDfQ2 NcAm31JlL3skiBtxmTxYti2QTqSp/iI4Vqmjitfg92Ou3t4lAM+suylagID+x0J0+tHu KE3mOC5Cm55nOQwpAapcpGecLX8hxh3rFiFDVDZCjpTatM4zH+6AnF3cKNUXaf/veMXq Fg== Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 3cufmy9jj3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 09 Dec 2021 11:16:06 +0000 Received: from m0098419.ppops.net (m0098419.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 1B9AtT4m026250 for ; Thu, 9 Dec 2021 11:16:06 GMT Received: from ppma03ams.nl.ibm.com (62.31.33a9.ip4.static.sl-reverse.com [169.51.49.98]) by mx0b-001b2d01.pphosted.com with ESMTP id 3cufmy9jh7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 09 Dec 2021 11:16:06 +0000 Received: from pps.filterd (ppma03ams.nl.ibm.com [127.0.0.1]) by ppma03ams.nl.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 1B9B7xoe032333; Thu, 9 Dec 2021 11:16:03 GMT Received: from b06cxnps3074.portsmouth.uk.ibm.com (d06relay09.portsmouth.uk.ibm.com [9.149.109.194]) by ppma03ams.nl.ibm.com with ESMTP id 3cqyyagfy8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 09 Dec 2021 11:16:03 +0000 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 1B9BG0pj28836218 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 9 Dec 2021 11:16:00 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C9ACEA4053; Thu, 9 Dec 2021 11:16:00 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8D795A404D; Thu, 9 Dec 2021 11:16:00 +0000 (GMT) Received: from osiris (unknown [9.145.88.158]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Thu, 9 Dec 2021 11:16:00 +0000 (GMT) Date: Thu, 9 Dec 2021 12:15:59 +0100 From: Heiko Carstens To: Philipp Rudo Cc: Alexander Egorenkov , ltao@redhat.com, linux-s390@vger.kernel.org Subject: Re: [PATCH v2 1/1] s390/kexec: handle R_390_PLT32DBL rela in arch_kexec_apply_relocations_add() Message-ID: References: <20211209073817.82196-1-egorenar@linux.ibm.com> <20211209120142.60642497@rhtmp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211209120142.60642497@rhtmp> X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: G1ATxrBy5dQgO5YLgdqAjytTyXJmphad X-Proofpoint-GUID: F3m_QsGepIVq0Izs4zbMWYhllMJudjhq X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2021-12-09_04,2021-12-08_01,2021-12-02_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 phishscore=0 adultscore=0 priorityscore=1501 suspectscore=0 mlxscore=0 spamscore=0 clxscore=1015 mlxlogscore=999 bulkscore=0 malwarescore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2110150000 definitions=main-2112090059 Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org On Thu, Dec 09, 2021 at 12:01:42PM +0100, Philipp Rudo wrote: > On Thu, 9 Dec 2021 08:38:17 +0100 > Alexander Egorenkov wrote: > > > Starting with gcc 11.3, the C compiler will generate PLT-relative function > > calls even if they are local and do not require it. Later on during linking, > > the linker will replace all PLT-relative calls to local functions with > > PC-relative ones. Unfortunately, the purgatory code of kexec/kdump is > > not being linked as a regular executable or shared library would have been, > > and therefore, all PLT-relative addresses remain in the generated purgatory > > object code unresolved. This leads to the situation where the purgatory > > code is being executed during kdump with all PLT-relative addresses > > unresolved. And this results in endless loops within the purgatory code. > > > > Furthermore, the clang C compiler has always behaved like described above > > and this commit should fix kdump for kernels built with the latter. > > > > Because the purgatory code is no regular executable or shared library, > > contains only calls to local functions and has no PLT, all R_390_PLT32DBL > > relocation entries can be resolved just like a R_390_PC32DBL one. ... > > Signed-off-by: Alexander Egorenkov > > Reported-by: Tao Liu > > Suggested-by: Philipp Rudo > > Thanks! > > Reviewed-by: Philipp Rudo Applied, thanks!