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 7BC32C43381 for ; Thu, 21 Feb 2019 12:10:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4BC3E20855 for ; Thu, 21 Feb 2019 12:10:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727694AbfBUMKV (ORCPT ); Thu, 21 Feb 2019 07:10:21 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:43294 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725774AbfBUMKU (ORCPT ); Thu, 21 Feb 2019 07:10:20 -0500 Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x1LC63nC146180 for ; Thu, 21 Feb 2019 07:10:19 -0500 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0a-001b2d01.pphosted.com with ESMTP id 2qst9nvafd-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 21 Feb 2019 07:10:18 -0500 Received: from localhost by e06smtp07.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) Thu, 21 Feb 2019 12:10:13 -0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x1LCAB5H21823580 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 21 Feb 2019 12:10:11 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6BD794C046; Thu, 21 Feb 2019 12:10:11 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id EE7CD4C040; Thu, 21 Feb 2019 12:10:10 +0000 (GMT) Received: from [9.152.224.140] (unknown [9.152.224.140]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 21 Feb 2019 12:10:10 +0000 (GMT) Reply-To: pmorel@linux.ibm.com Subject: Re: [PATCH v2 1/1] s390: vfio_ap: link the vfio_ap devices to the vfio_ap bus subsystem To: Halil Pasic , Cornelia Huck Cc: Tony Krowiak , borntraeger@de.ibm.com, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, frankja@linux.ibm.com, david@redhat.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, freude@linux.ibm.com References: <1550513328-12646-1-git-send-email-pmorel@linux.ibm.com> <1550513328-12646-2-git-send-email-pmorel@linux.ibm.com> <8e6853ba-12ed-a4f3-1263-0e15f715b644@linux.ibm.com> <6cc5b478-4678-9a82-b902-cc9aed22becf@linux.ibm.com> <20190220102731.4fca4f91.cohuck@redhat.com> <20190220135108.49f8f891@oc2783563651> From: Pierre Morel Date: Thu, 21 Feb 2019 13:10:10 +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: <20190220135108.49f8f891@oc2783563651> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 19022112-0028-0000-0000-0000034B46D2 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19022112-0029-0000-0000-000024098B28 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-02-21_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=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-1902210090 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20/02/2019 13:51, Halil Pasic wrote: > On Wed, 20 Feb 2019 10:27:31 +0100 > Cornelia Huck wrote: > >> On Tue, 19 Feb 2019 22:31:17 +0100 >> Pierre Morel wrote: >> >>> On 19/02/2019 19:52, Tony Krowiak wrote: >>>> On 2/18/19 1:08 PM, Pierre Morel wrote: >>>>> Libudev relies on having a subsystem link for non-root devices. To ...snip... >>>>> + >>>>> +static struct device_driver matrix_driver = { >>>>> +    .name = "vfio_ap", >>>> >>>> This is the same name used for the original device driver. I think >>>> this driver ought to have a different name to avoid confusion. >>>> How about vfio_ap_matrix or some other name to differentiate the >>>> two. >>> >>> I would like too, but changing this will change the path to the mediated >>> device supported type. >> >> Yes, we don't want to change that. >> > > Nod. However if I cannot change the driver name, I can change the bus name to matrix. At least one less "vfio_ap" name > >>> >>> >>>> >>>>> +    .bus = &matrix_bus, >>>>> +    .probe = matrix_probe, >>>> >>>> I would add: >>>>     .suppress_bind_attrs = true; >>>> >>>> This will remove the sysfs bind/unbind interfaces. Since there is only >>>> one matrix device and it's lifecycle is controlled herein, there is no >>>> sense in allowing a root user to bind/unbind it. >>>> >>> >>> OTOH bind/unbind has no impact. >>> If no one else ask for this I will not change what has already been >>> reviewed by Conny and Christian. >> >> As we only have one driver, it does not really make sense anyway. >> > > I see this as a reason to suppress_bind_attrs. It is much easier than to > think about what should happen when one unbinds the matrix device from > the vfio_ap driver on the vfio_ap bus. With the code as is it seems to > just keep working as if nothing happened. > And /sys/devices/vfio_ap/matrix/mdev_supported_types/ referencing the > name of the driver that is already gone sounds a bit weird. > > Regards, > Halil > If there is no objection I will do this, It seems more logical to me too. Regards, Pierre -- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany