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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 21E3BC282C4 for ; Mon, 4 Feb 2019 10:06:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EFDF32087C for ; Mon, 4 Feb 2019 10:06:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729269AbfBDKGS (ORCPT ); Mon, 4 Feb 2019 05:06:18 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:48332 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727217AbfBDKGR (ORCPT ); Mon, 4 Feb 2019 05:06:17 -0500 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x149t5iQ113373 for ; Mon, 4 Feb 2019 05:06:16 -0500 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0b-001b2d01.pphosted.com with ESMTP id 2qejxx9dc2-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 04 Feb 2019 05:06:16 -0500 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 4 Feb 2019 10:06:13 -0000 Received: from d06av21.portsmouth.uk.ibm.com (d06av21.portsmouth.uk.ibm.com [9.149.105.232]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x14A6BHx2228626 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 4 Feb 2019 10:06:11 GMT Received: from d06av21.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6F9675204E; Mon, 4 Feb 2019 10:06:11 +0000 (GMT) Received: from [10.0.2.15] (unknown [9.152.224.114]) by d06av21.portsmouth.uk.ibm.com (Postfix) with ESMTP id EA2CB52050; Mon, 4 Feb 2019 10:06:10 +0000 (GMT) Subject: Re: [PATCH] zcrypt: handle AP Info notification from CHSC SEI command To: Tony Krowiak , Heiko Carstens Cc: Sebastian Ott , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Martin Schwidefsky , oberpar@linux.ibm.com, pmorel@linux.ibm.com, pasic@linux.ibm.com, cohuck@redhat.com References: <1548870526-30595-1-git-send-email-akrowiak@linux.ibm.com> <88b72363-9dca-4653-c326-9c37b6349a32@linux.ibm.com> <20190201090159.GC3770@osiris> From: Harald Freudenberger Date: Mon, 4 Feb 2019 11:06:13 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Content-Language: en-US X-TM-AS-GCONF: 00 x-cbid: 19020410-0020-0000-0000-0000031148A3 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19020410-0021-0000-0000-000021625365 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-02-04_07:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1902040080 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01.02.19 16:38, Tony Krowiak wrote: > On 2/1/19 4:01 AM, Heiko Carstens wrote: >> On Thu, Jan 31, 2019 at 06:28:39PM -0500, Tony Krowiak wrote: >>> On 1/30/19 1:32 PM, Sebastian Ott wrote: >>>> On Wed, 30 Jan 2019, Tony Krowiak wrote: >>>>> +#if IS_ENABLED(CONFIG_ZCRYPT) >>>>> +void ap_bus_cfg_chg(void); >>>>> +#else >>>>> +#error "no CONFIG_ZCRYPT" >>>>     ^ >>>> I don't think that's the right thing to do here. >>> >>> I'd like to leave it. If somebody edits .config >>> and sets CONFIG_ZCRYPT=n, then the build will >>> fail. The preprocessor error above tells them >>> why. >> >> No, the kernel build should never fail if a config option is not set. >> Also the above should be "#ifdef CONFIG_ZCRYPT". > > Will do. > >> >> In addition (this isn't quoted unfortunately) the alternative function >> in the header file is missing the "inline" attribute. Can you please >> add that too? > > I can. > >> >> static inline void ap_bus_cfg_chg(void) { } >> >>>>> +* A config change has happened, Force an ap bus rescan. >>>>> +*/ >>>>> +void ap_bus_cfg_chg(void) >>>>> +{ >>>>> +    AP_DBF(DBF_INFO, "%s config change, forcing bus rescan\n", __func__); >>>>> + >>>>> +    ap_bus_force_rescan(); >>>>> +} >>>>> +EXPORT_SYMBOL(ap_bus_cfg_chg); >>>> >>>> There is no need for the export symbol - you don't call that function >>> >from module code. >>>> As an unrelated question, just to be sure: ap_bus.c is compiled as >>>> built-in even with ZCRYPT=m, right? >>> >>> No. If you edit .config and set CONFIG_ZCRYPT=m, ap_bus.c will be built >>> into the zcrypt.ko module. Through some other magic, the zcrypt module >>> is loaded when linux boots. >> >> If that happens, then we have a build problem that needs to be >> fixed. What exactly are you doing to get the ap code linked into the >> zcrypt module? > > To tell you the truth, I don't know. The build configuration precedes my > creating this patch by many years. I only discovered these anomalies by > playing with the CONFIG_ZCRYPT option in response to Sebastian's > comments. I will have to take this up with our internal IBM maintainer. > >> > As Martin already pointed out the ap bus code is statically build into the kernel with this line in the Makefile:   obj-$(subst m,y,$(CONFIG_ZCRYPT)) += ap.o So CONFIG_ZCRYPT may have the value 'm' or 'y' and this is also the reason why a simple #ifdef CONFIG_ZCRYPT does not work, instead #if IS_ENABLED(CONFIG_ZCRYPT) has to be used. Only the ap stuff (which is: ap_bus.o, ap_card.o and ap_queue.o) is statically build into the kernel. The zcrypt kernel module is loaded as a dependency when a crypto card is detected. So detecting a CEX4 forces kernel module zcrypt_cex4.ko which forces the zcrypt.ko to insert into the kernel. So all global functions in ap_bus.c are available when CONFIG_ZCRYPT is enabled. However, I thought the symbol still needs an EXPORT_SYMBOL() statement. Otherwise I should throw out all these statements. Harald