From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:50624 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2439076AbfJXLlw (ORCPT ); Thu, 24 Oct 2019 07:41:52 -0400 Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x9OBc062108156 for ; Thu, 24 Oct 2019 07:41:52 -0400 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0a-001b2d01.pphosted.com with ESMTP id 2vu9nxm0gx-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 24 Oct 2019 07:41:51 -0400 Received: from localhost by e06smtp07.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 24 Oct 2019 12:41:49 +0100 From: Janosch Frank Subject: [RFC 01/37] DOCUMENTATION: protvirt: Protected virtual machine introduction Date: Thu, 24 Oct 2019 07:40:23 -0400 In-Reply-To: <20191024114059.102802-1-frankja@linux.ibm.com> References: <20191024114059.102802-1-frankja@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-Id: <20191024114059.102802-2-frankja@linux.ibm.com> Sender: linux-s390-owner@vger.kernel.org List-ID: To: kvm@vger.kernel.org Cc: linux-s390@vger.kernel.org, thuth@redhat.com, david@redhat.com, borntraeger@de.ibm.com, imbrenda@linux.ibm.com, mihajlov@linux.ibm.com, mimu@linux.ibm.com, cohuck@redhat.com, gor@linux.ibm.com, frankja@linux.ibm.com Introduction to Protected VMs. Signed-off-by: Janosch Frank --- Documentation/virtual/kvm/s390-pv.txt | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 Documentation/virtual/kvm/s390-pv.txt diff --git a/Documentation/virtual/kvm/s390-pv.txt b/Documentation/virtual/kvm/s390-pv.txt new file mode 100644 index 000000000000..86ed95f36759 --- /dev/null +++ b/Documentation/virtual/kvm/s390-pv.txt @@ -0,0 +1,23 @@ +Ultravisor and Protected VMs +=========================== + +Summary: + +Protected VMs (PVM) are KVM VMs, where KVM can't access the VM's state +like guest memory and guest registers anymore. Instead the PVMs are +mostly managed by a new entity called Ultravisor (UV), which provides +an API, so KVM and the PVM can request management actions. + +Each guest starts in the non-protected mode and then transitions into +protected mode. On transition KVM registers the guest and its VCPUs +with the Ultravisor and prepares everything for running it. + +The Ultravisor will secure and decrypt the guest's boot memory +(i.e. kernel/initrd). It will safeguard state changes like VCPU +starts/stops and injected interrupts while the guest is running. + +As access to the guest's state, like the SIE state description is +normally needed to be able to run a VM, some changes have been made in +SIE behavior and fields have different meaning for a PVM. SIE exits +are minimized as much as possible to improve speed and reduce exposed +guest state. -- 2.20.1