Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751170AbdFBHG2 (ORCPT ); Fri, 2 Jun 2017 03:06:28 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:35783 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750918AbdFBHG1 (ORCPT ); Fri, 2 Jun 2017 03:06:27 -0400 Date: Fri, 2 Jun 2017 09:06:18 +0200 From: Heiko Carstens To: David Hildenbrand Cc: Martin Schwidefsky , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Thomas Huth , Christian Borntraeger Subject: Re: [PATCH RFC 0/2] KVM: s390: avoid having to enable vm.alloc_pgste References: <20170529163202.13077-1-david@redhat.com> <20170601124651.3e7969ab@mschwideX1> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-TM-AS-GCONF: 00 x-cbid: 17060207-0008-0000-0000-0000045CE36E X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17060207-0009-0000-0000-00001DE238DF Message-Id: <20170602070618.GB4221@osiris> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-06-02_03:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1706020134 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 536 Lines: 12 On Thu, Jun 01, 2017 at 01:27:28PM +0200, David Hildenbrand wrote: > An alternative: Have some process that enables PGSTE for all of its > future children. Fork+execv qemu. However, such a process in between > will most likely confuse tooling like libvirt when it comes to process ids. That would be something like sys_personality() vs setarch, e.g. adding a new s390 specific personality flag and then do something like setarch s390x --kvm qemu... However I'm afraid that this is also not acceptable from a usability point of view.