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=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS autolearn=unavailable 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 C0CA4C43387 for ; Mon, 17 Dec 2018 17:32:39 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1FA3620675 for ; Mon, 17 Dec 2018 17:32:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1FA3620675 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 43JSsK03NNzDqpd for ; Tue, 18 Dec 2018 04:32:36 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=linux.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=sebott@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 43JSpv6ZWmzDqWH for ; Tue, 18 Dec 2018 04:30:30 +1100 (AEDT) Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id wBHHSVxZ081026 for ; Mon, 17 Dec 2018 12:30:28 -0500 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 2pef79k6y7-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 17 Dec 2018 12:30:28 -0500 Received: from localhost by e06smtp03.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 17 Dec 2018 17:30:25 -0000 Received: from b06cxnps4075.portsmouth.uk.ibm.com (9.149.109.197) by e06smtp03.uk.ibm.com (192.168.101.133) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 17 Dec 2018 17:30:21 -0000 Received: from d06av21.portsmouth.uk.ibm.com (d06av21.portsmouth.uk.ibm.com [9.149.105.232]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id wBHHUKGF131406 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 17 Dec 2018 17:30:20 GMT Received: from d06av21.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 76C8A52054; Mon, 17 Dec 2018 17:30:20 +0000 (GMT) Received: from sig-9-145-45-130.uk.ibm.com (unknown [9.145.45.130]) by d06av21.portsmouth.uk.ibm.com (Postfix) with ESMTPS id 8B20D52052; Mon, 17 Dec 2018 17:30:19 +0000 (GMT) Date: Mon, 17 Dec 2018 18:30:18 +0100 (CET) From: Sebastian Ott X-X-Sender: sebott@schleppi To: Christoph Hellwig Subject: Re: [PATCH 2/2] s390/pci: handle function enumeration after sriov enablement In-Reply-To: <20181214131802.GA13950@infradead.org> References: <20181212215453.GJ99796@google.com> <20181213175428.87520-2-sebott@linux.ibm.com> <20181214131245.GB2606@infradead.org> <20181214131802.GA13950@infradead.org> User-Agent: Alpine 2.21 (LFD 202 2017-01-01) Organization: =?ISO-8859-15?Q?=22IBM_Deutschland_Research_&_Development_GmbH?= =?ISO-8859-15?Q?_=2F_Vorsitzende_des_Aufsichtsrats=3A_Matthias?= =?ISO-8859-15?Q?_Hartmann_Gesch=E4ftsf=FChrung=3A_Dirk_Wittkopp?= =?ISO-8859-15?Q?_Sitz_der_Gesellschaft=3A_B=F6blingen_=2F_Reg?= =?ISO-8859-15?Q?istergericht=3A_Amtsgericht_Stuttgart=2C_HRB_2432?= =?ISO-8859-15?Q?94=22?= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-TM-AS-GCONF: 00 x-cbid: 18121717-0012-0000-0000-000002DA5F35 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18121717-0013-0000-0000-0000210FF450 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2018-12-17_06:, , 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=1015 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-1812170155 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Arnd Bergmann , linux-pci@vger.kernel.org, Paul Mackerras , Bjorn Helgaas , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Fri, 14 Dec 2018, Christoph Hellwig wrote: > On Fri, Dec 14, 2018 at 05:12:45AM -0800, Christoph Hellwig wrote: > > On Thu, Dec 13, 2018 at 06:54:28PM +0100, Sebastian Ott wrote: > > > Implement pcibios_sriov_{add|del}_vfs as empty functions. VF > > > creation will be triggered by the hotplug code. > > > > And instead of having the arch suplply a no-op arch override I > > think it would be better to have the config option just stub it > > out in common code. > > Or in fact maybe even a runtime flag in struct pci_dev. Who knows > if all future s390 PCIe busses will have exactly the same behavior > or if we eventually get the standards compliant behvior back? Something like this: https://lore.kernel.org/linux-pci/20181212215453.GJ99796@google.com/T/#m649d86ea3c65f669c74d048f89afbaf473876ac3 Not a runtime flag, but a function pointer in struct pci_host_bridge. This would provide the requested flexibility. The problem with this approach is that it requires other patches that are not yet upstream (https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/log/?h=pci-probe-rework). Since this discussion is going on since a few months and I want to have this code upstream and in distributions for HW enablement I've asked Bjorn to go with the initial approach (weak functions) and promised to move that to struct pci_host_bridge once Arnd's patches are upstream. Would that be OK for you too? Regards, Sebastian