From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934997AbdKPQHS (ORCPT ); Thu, 16 Nov 2017 11:07:18 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:45506 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933317AbdKPQHK (ORCPT ); Thu, 16 Nov 2017 11:07:10 -0500 Subject: Re: [RFC 00/19] KVM: s390/crypto/vfio: guest dedicated crypto adapters To: Tony Krowiak , Cornelia Huck Cc: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, freude@de.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, borntraeger@de.ibm.com, kwankhede@nvidia.com, bjsdjshi@linux.vnet.ibm.com, pbonzini@redhat.com, alex.williamson@redhat.com, alifm@linux.vnet.ibm.com, mjrosato@linux.vnet.ibm.com, qemu-s390x@nongnu.org, jjherne@linux.vnet.ibm.com, thuth@redhat.com, pasic@linux.vnet.ibm.com References: <1507916344-3896-1-git-send-email-akrowiak@linux.vnet.ibm.com> <5baf5f90-6cac-3c09-7b66-1bc8b30b8093@linux.vnet.ibm.com> <20171114145722.4ab850a5.cohuck@redhat.com> From: Pierre Morel Date: Thu, 16 Nov 2017 17:06:58 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 17111616-0040-0000-0000-000003EF221F X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17111616-0041-0000-0000-000025F1DC37 Message-Id: <8a492b07-3d3b-f4cf-e139-7de345ea8188@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-11-16_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 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1711160217 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 16/11/2017 16:23, Tony Krowiak wrote: > On 11/14/2017 08:57 AM, Cornelia Huck wrote: >> On Tue, 31 Oct 2017 15:39:09 -0400 >> Tony Krowiak wrote: >> >>> On 10/13/2017 01:38 PM, Tony Krowiak wrote: >>> Ping >>>> Tony Krowiak (19): >>>>     KVM: s390: SIE considerations for AP Queue virtualization >>>>     KVM: s390: refactor crypto initialization >>>>     s390/zcrypt: new AP matrix bus >>>>     s390/zcrypt: create an AP matrix device on the AP matrix bus >>>>     s390/zcrypt: base implementation of AP matrix device driver >>>>     s390/zcrypt: register matrix device with VFIO mediated device >>>>       framework >>>>     KVM: s390: introduce AP matrix configuration interface >>>>     s390/zcrypt: support for assigning adapters to matrix mdev >>>>     s390/zcrypt: validate adapter assignment >>>>     s390/zcrypt: sysfs interfaces supporting AP domain assignment >>>>     s390/zcrypt: validate domain assignment >>>>     s390/zcrypt: sysfs support for control domain assignment >>>>     s390/zcrypt: validate control domain assignment >>>>     KVM: s390: Connect the AP mediated matrix device to KVM >>>>     s390/zcrypt: introduce ioctl access to VFIO AP Matrix driver >>>>     KVM: s390: interface to configure KVM guest's AP matrix >>>>     KVM: s390: validate input to AP matrix config interface >>>>     KVM: s390: New ioctl to configure KVM guest's AP matrix >>>>     s390/facilities: enable AP facilities needed by guest >> I think the approach is fine, and the code also looks fine for the most >> part. Some comments: >> >> - various patches can be squashed together to give a better >>    understanding at a glance > Which patches would you squash? >> - this needs documentation (as I already said) > My plan is to take the cover letter patch and incorporate that into > documentation, > then replace the cover letter patch with a more concise summary. >> - some of the driver/device modelling feels a bit awkward (commented in >>    patches) -- I'm not sure that my proposal is better, but I think we >>    should make sure the interdependencies are modeled correctly > I am responding to each patch review individually. I think that instead of responding to each patch individually we should have a discussion on the design because I think a lot could change and discussing about each patch as they may be completely redesigned for the next version may not be very useful. So I totally agree with Conny on that we should stabilize the bus/device/driver modeling. I think it would be here a good place to start the discussion on things like we started to discuss, Harald and I, off-line: - why a matrix bus, in which case we can avoid it - which kind of devices we need - how to handle the repartition of queues on boot, reset and hotplug - interaction with the host drivers - validation of the matrix for guests and host views or even features we need to add like - interruptions - PAPQ/TAPQ-t and APQI interception - virtualization of the AP - CPU model and KVM capabilities In my understanding these points must be cleared before we really start to discuss the details of the implementation. Best regards, Pierre >> - some minor stuff >> > -- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany