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 B95C9C73C53 for ; Tue, 9 Jul 2019 21:11:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9CD57208C4 for ; Tue, 9 Jul 2019 21:11:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727266AbfGIVL1 (ORCPT ); Tue, 9 Jul 2019 17:11:27 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:22480 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726318AbfGIVL1 (ORCPT ); Tue, 9 Jul 2019 17:11:27 -0400 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 x69L83Zx101361; Tue, 9 Jul 2019 17:11:24 -0400 Received: from ppma01wdc.us.ibm.com (fd.55.37a9.ip4.static.sl-reverse.com [169.55.85.253]) by mx0a-001b2d01.pphosted.com with ESMTP id 2tn1bcjskg-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 09 Jul 2019 17:11:24 -0400 Received: from pps.filterd (ppma01wdc.us.ibm.com [127.0.0.1]) by ppma01wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id x69L9eho030322; Tue, 9 Jul 2019 21:11:23 GMT Received: from b01cxnp22033.gho.pok.ibm.com (b01cxnp22033.gho.pok.ibm.com [9.57.198.23]) by ppma01wdc.us.ibm.com with ESMTP id 2tjk96fq36-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 09 Jul 2019 21:11:23 +0000 Received: from b01ledav001.gho.pok.ibm.com (b01ledav001.gho.pok.ibm.com [9.57.199.106]) by b01cxnp22033.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x69LBLiS36962590 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 9 Jul 2019 21:11:21 GMT Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 113D228059; Tue, 9 Jul 2019 21:11:21 +0000 (GMT) Received: from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id BC6C82805C; Tue, 9 Jul 2019 21:11:20 +0000 (GMT) Received: from [9.60.75.173] (unknown [9.60.75.173]) by b01ledav001.gho.pok.ibm.com (Postfix) with ESMTP; Tue, 9 Jul 2019 21:11:20 +0000 (GMT) Subject: Re: [PATCH v4 3/7] s390: zcrypt: driver callback to indicate resource in use To: Cornelia Huck Cc: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, freude@linux.ibm.com, borntraeger@de.ibm.com, frankja@linux.ibm.com, david@redhat.com, mjrosato@linux.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, pmorel@linux.ibm.com, pasic@linux.ibm.com, alex.williamson@redhat.com, kwankhede@nvidia.com References: <1560454780-20359-1-git-send-email-akrowiak@linux.ibm.com> <1560454780-20359-4-git-send-email-akrowiak@linux.ibm.com> <20190618182558.7d7e025a.cohuck@redhat.com> <2366c6b6-fd9e-0c32-0e9d-018cd601a0ad@linux.ibm.com> <20190701212643.0dd7d4ab.cohuck@redhat.com> <20190709124920.3a910dca.cohuck@redhat.com> From: Tony Krowiak Message-ID: <089663dd-2e6d-cbb7-c1ef-a8a4b325abd3@linux.ibm.com> Date: Tue, 9 Jul 2019 17:11:20 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20190709124920.3a910dca.cohuck@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-07-09_08:,, 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-1907090253 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On 7/9/19 6:49 AM, Cornelia Huck wrote: > On Mon, 8 Jul 2019 10:27:11 -0400 > Tony Krowiak wrote: > >> On 7/1/19 3:26 PM, Cornelia Huck wrote: >>> On Wed, 19 Jun 2019 09:04:18 -0400 >>> Tony Krowiak wrote: > >>>> Allow me to first address your fear that a bad actor can hog >>>> resources that can't be removed by root. With this enhancement, >>>> there is nothing preventing a root user from taking resources >>>> from a matrix mdev, it simply forces him/her to follow the >>>> proper procedure. The resources to be removed must first be >>>> unassigned from the matrix mdev to which they are assigned. >>>> The AP bus's /sys/bus/ap/apmask and /sys/bus/ap/aqmask >>>> sysfs attributes can then be edited to transfer ownership >>>> of the resources to zcrypt. >>> >>> What is the suggested procedure when root wants to unbind a queue >>> device? Find the mdev using the queue (is that easy enough?), unassign >>> it, then unbind? Failing to unbind is a bit unexpected; can we point >>> the admin to the correct mdev from which the queue has to be removed >>> first? >> >> The proper procedure is to first unassign the adapter, domain, or both >> from the mdev to which the APQN is assigned. The difficulty in finding >> the queue depends upon how many mdevs have been created. I would expect >> that an admin would keep records of who owns what, but in the case he or >> she doesn't, it would be a matter of printing out the matrix attribute >> of each mdev until you find the mdev to which the APQN is assigned. > > Ok, so the information is basically available, if needed. > >> The only means I know of for informing the admin to which mdev a given >> APQN is assigned is to log the error when it occurs. > > That might be helpful, if it's easy to do. > >> I think Matt is >> also looking to provide query functions in the management tool on which >> he is currently working. > > That also sounds helpful. > > (...) > >>>> * It forces the use of the proper procedure to change ownership of AP >>>> queues. >>> >>> This needs to be properly documented, and the admin needs to have a >>> chance to find out why unbinding didn't work and what needs to be done >>> (see my comments above). >> >> I will create a section in the vfio-ap.txt document that comes with this >> patch set describing the proper procedure for unbinding queues. Of >> course, we'll make sure the official IBM doc also more thoroughly >> describes this. > > +1 for good documentation. > > With that, I don't really object to this change. Then I will make the suggested changes and post v5 to the list. >