From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755617AbdKCIt6 (ORCPT ); Fri, 3 Nov 2017 04:49:58 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:43780 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751754AbdKCItz (ORCPT ); Fri, 3 Nov 2017 04:49:55 -0400 Subject: Re: [RFC 19/19] s390/facilities: enable AP facilities needed by guest To: Harald Freudenberger , Tony Krowiak Cc: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, heicars2@linux.vnet.ibm.com, cohuck@redhat.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, qemu-s390x@nongnu.org, jjherne@linux.vnet.ibm.com, thuth@redhat.com, pasic@linux.vnet.ibm.com, borntrAE@linux.vnet.ibm.com References: <1507916344-3896-1-git-send-email-akrowiak@linux.vnet.ibm.com> <1507916344-3896-20-git-send-email-akrowiak@linux.vnet.ibm.com> <20171016112510.39e9c330@mschwideX1> <3e836f59-3ef1-57d8-d6df-b66011c173c4@de.ibm.com> From: Christian Borntraeger Date: Fri, 3 Nov 2017 09:49:46 +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=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 17110308-0008-0000-0000-000004A718B8 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17110308-0009-0000-0000-00001E39A47A Message-Id: <718086fa-9f9e-e474-371e-cf0a89f5460c@de.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-11-03_03:,, 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=8.0.1-1707230000 definitions=main-1711030111 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/03/2017 09:14 AM, Harald Freudenberger wrote: > I talked with the firmware guys about this. > The answer is that the AP 3 instructions (NQAP, DQAP, PQAP) are always available. That is true for basic mode and LPAR, but certainly not for z/VM or KVM guests. > Tony is right with the facility bits. > facility bit 15 tells if the T bit is supported with the PQAP(TAPQ) subcommand, > facility bit 12 tells if the PQAP(QCI) subcommand is available. > > As far as I could discover the AP instructions where optional on some older machines. > This may be the reason why zVM throws an exception if there is no AP device assigned. > However, for all machines still in service the AP instructions are available at al time. We have to distinguish LPARs and 2nd level guests under KVM/z/VM. For those 2nd level guests there are configurations out there TODAY that do not support PQAP and friends.