From patchwork Thu May 14 06:41:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gibson X-Patchwork-Id: 11548045 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C6761913 for ; Thu, 14 May 2020 06:41:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B14D0206D4 for ; Thu, 14 May 2020 06:41:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.b="fB9fqGJY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726121AbgENGli (ORCPT ); Thu, 14 May 2020 02:41:38 -0400 Received: from ozlabs.org ([203.11.71.1]:53937 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726154AbgENGlf (ORCPT ); Thu, 14 May 2020 02:41:35 -0400 Received: by ozlabs.org (Postfix, from userid 1007) id 49N24m4Jt2z9sTx; Thu, 14 May 2020 16:41:28 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gibson.dropbear.id.au; s=201602; t=1589438488; bh=W558T0y4xrxfOwPQYmYtDO1muLcuKoHvSX6UyLLotaM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fB9fqGJYyzheB8if3//YhAR/An4KQPyAs5sI7FR27xhVTovgDxaMGAiafODtkGE0U bDKvn2jFjibFAqtRDoTg5d6Z4EskKVzldT8xMYpvKU7vcM5NQlMzW2k+dujnxRJ8Xz DEg4o9XDg96/n8pewfoOIx7+LFB9BqIUVEKXGiP4= From: David Gibson To: dgilbert@redhat.com, frankja@linux.ibm.com, pair@us.redhat.com, qemu-devel@nongnu.org, brijesh.singh@amd.com Cc: kvm@vger.kernel.org, qemu-ppc@nongnu.org, David Gibson , Richard Henderson , cohuck@redhat.com, Paolo Bonzini , Marcel Apfelbaum , "Michael S. Tsirkin" , Eduardo Habkost , qemu-devel@nongnu.-rg, mdroth@linux.vnet.ibm.com Subject: [RFC 17/18] spapr: Added PEF based guest memory protection Date: Thu, 14 May 2020 16:41:19 +1000 Message-Id: <20200514064120.449050-18-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200514064120.449050-1-david@gibson.dropbear.id.au> References: <20200514064120.449050-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Some upcoming POWER machines have a system called PEF (Protected Execution Framework) which uses a small ultravisor to allow guests to run in a way that they can't be eavesdropped by the hypervisor. The effect is roughly similar to AMD SEV, although the mechanisms are quite different. Most of the work of this is done between the guest, KVM and the ultravisor, with little need for involvement by qemu. However qemu does need to tell KVM to allow secure VMs. Because the availability of secure mode is a guest visible difference which depends on havint the right hardware and firmware, we don't enable this by default. In order to run a secure guest you need to create a "pef-guest" object and set the guest-memory-protection machine property to point to it. Note that this just *allows* secure guests, the architecture of PEF is such that the guest still needs to talk to the ultravisor to enter secure mode, so we can't know if the guest actually is secure until well after machine creation time. Signed-off-by: David Gibson --- target/ppc/Makefile.objs | 2 +- target/ppc/pef.c | 81 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 82 insertions(+), 1 deletion(-) create mode 100644 target/ppc/pef.c diff --git a/target/ppc/Makefile.objs b/target/ppc/Makefile.objs index e8fa18ce13..ac93b9700e 100644 --- a/target/ppc/Makefile.objs +++ b/target/ppc/Makefile.objs @@ -6,7 +6,7 @@ obj-y += machine.o mmu_helper.o mmu-hash32.o monitor.o arch_dump.o obj-$(TARGET_PPC64) += mmu-hash64.o mmu-book3s-v3.o compat.o obj-$(TARGET_PPC64) += mmu-radix64.o endif -obj-$(CONFIG_KVM) += kvm.o +obj-$(CONFIG_KVM) += kvm.o pef.o obj-$(call lnot,$(CONFIG_KVM)) += kvm-stub.o obj-y += dfp_helper.o obj-y += excp_helper.o diff --git a/target/ppc/pef.c b/target/ppc/pef.c new file mode 100644 index 0000000000..823daf3e9c --- /dev/null +++ b/target/ppc/pef.c @@ -0,0 +1,81 @@ +/* + * PEF (Protected Execution Framework) for POWER support + * + * Copyright David Gibson, Redhat Inc. 2020 + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#include "qemu/osdep.h" + +#define TYPE_PEF_GUEST "pef-guest" +#define PEF_GUEST(obj) \ + OBJECT_CHECK(PefGuestState, (obj), TYPE_SEV_GUEST) + +typedef struct PefGuestState PefGuestState; + +/** + * PefGuestState: + * + * The PefGuestState object is used for creating and managing a PEF + * guest. + * + * # $QEMU \ + * -object pef-guest,id=pef0 \ + * -machine ...,guest-memory-protection=pef0 + */ +struct PefGuestState { + Object parent_obj; +}; + +static Error *pef_mig_blocker; + +static int pef_kvm_init(GuestMemoryProtection *gmpo, Error **errp) +{ + PefGuestState *pef = PEF_GUEST(gmpo); + + if (!kvm_check_extension(kvm_state, KVM_CAP_PPC_SECURE_GUEST)) { + error_setg(errp, + "KVM implementation does not support Secure VMs (is an ultravisor running?)"); + return -1; + } else { + int ret = kvm_vm_enable_cap(kvm_state, KVM_CAP_PPC_SECURE_GUEST, 0, 1); + + if (ret < 0) { + error_setg(errp, + "Error enabling PEF with KVM"); + return -1; + } + } + + return 0; +} + +static void pef_guest_class_init(ObjectClass *oc, void *data) +{ + GuestMemoryProtectionClass *gmpc = GUEST_MEMORY_PROTECTION_CLASS(oc); + + gmpc->kvm_init = pef_kvm_init; +} + +static const TypeInfo pef_guest_info = { + .parent = TYPE_OBJECT, + .name = TYPE_PEF_GUEST, + .instance_size = sizeof(PefGuestState), + .class_init = pef_guest_class_init, + .interfaces = (InterfaceInfo[]) { + { TYPE_GUEST_MEMORY_PROTECTION }, + { TYPE_USER_CREATABLE }, + { } + } +}; + +static void +pef_register_types(void) +{ + type_register_static(&pef_guest_info); +} + +type_init(pef_register_types);