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=-0.8 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 0C0C0C43382 for ; Fri, 28 Sep 2018 10:16:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B51302172C for ; Fri, 28 Sep 2018 10:16:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B51302172C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729289AbeI1QjQ (ORCPT ); Fri, 28 Sep 2018 12:39:16 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54034 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728936AbeI1QjP (ORCPT ); Fri, 28 Sep 2018 12:39:15 -0400 Received: from smtp.corp.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.26]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B914D6662; Fri, 28 Sep 2018 10:16:12 +0000 (UTC) Received: from gondolin (dhcp-192-215.str.redhat.com [10.33.192.215]) by smtp.corp.redhat.com (Postfix) with ESMTP id 093363091390; Fri, 28 Sep 2018 10:16:06 +0000 (UTC) Date: Fri, 28 Sep 2018 12:16:04 +0200 From: Cornelia Huck To: Tony Krowiak 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, pmorel@linux.vnet.ibm.com, alifm@linux.vnet.ibm.com, mjrosato@linux.vnet.ibm.com, jjherne@linux.vnet.ibm.com, thuth@redhat.com, pasic@linux.vnet.ibm.com, berrange@redhat.com, fiuczy@linux.vnet.ibm.com, buendgen@de.ibm.com, frankja@linux.ibm.com, Tony Krowiak Subject: Re: [PATCH v11 00/26] guest dedicated crypto adapters Message-ID: <20180928121604.65874dc1.cohuck@redhat.com> In-Reply-To: <20180925231641.4954-1-akrowiak@linux.vnet.ibm.com> References: <20180925231641.4954-1-akrowiak@linux.vnet.ibm.com> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.26 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Fri, 28 Sep 2018 10:16:13 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 25 Sep 2018 19:16:15 -0400 Tony Krowiak wrote: > Abstract: > ======== > > On s390, we have cryptographic coprocessor cards, which are modeled on > Linux as devices on the AP bus. Each card can be partitioned into domains > which can be thought of as a set of hardware registers for processing > crypto commands. Crypto commands are sent to a specific domain within a > card is via a queue which is identified as a (card,domain) tuple. We model > this something like the following (assuming we have access to cards 3 and > 4 and domains 1 and 2): > > AP -> card3 -> queue (3,1) > -> queue (3,2) > -> card4 -> queue (4,1) > -> queue (4,2) > > If we want to virtualize this, we can use a feature provided by the > hardware. We basically attach a satellite control block to our main > hardware virtualization control block and the hardware takes care of > most of the rest. > > For this control block, we don't specify explicit tuples, but a list of > cards and a list of domains. The guest will get access to the cross > product. > > Because of this, we need to take care that the lists provided to > different guests don't overlap; i.e., we need to enforce sane > configurations. Otherwise, one guest may get access to things like > secret keys for another guest. > > The idea of this patch set is to introduce a new device, the matrix > device. This matrix device hangs off a different root and acts as the > parent node for mdev devices. > > If you now want to give the tuples (4,1) and (4,2), you need to do the > following: > > - Make sure the queues (4,1) and (4,2) belong to vfio_ap (see patches > #5 and #6) > - Create the mediated device. > - Assign card 4 and domains 1 and 2 to the mediated device > - Optionally activate the mediated device. > > QEMU will now simply consume the mediated device and things should work. > > For a complete description of the architecture and concepts underlying > the design, see the Documentation/s390/vfio-ap.txt file included with this > patch set. > > v10 => v11 Change log: > ===================== > * Fixed race condition when setting KVM in the notifier > * Removed KVM_S390_VM_CPU_FEAT_AP, no longer necessary > * Fail vfio_ap module inti if AP instructions not available on host > * Remove KVM_S390_VM_CPU_FEAT_AP > * Expose VM enable/disable APIE attributes only if AP instructions > available on host. I think this version is good to go with the touchups mentioned.