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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 CF426C4361A for ; Fri, 4 Dec 2020 18:33:09 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 55E4522582 for ; Fri, 4 Dec 2020 18:33:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 55E4522582 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:41194 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1klFtE-000820-0G for qemu-devel@archiver.kernel.org; Fri, 04 Dec 2020 13:33:08 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:33184) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1klEXp-0006dg-F7 for qemu-devel@nongnu.org; Fri, 04 Dec 2020 12:07:08 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:29706) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1klEWc-00051B-KO for qemu-devel@nongnu.org; Fri, 04 Dec 2020 12:06:34 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1607101482; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=HZCsLXtKca3nNAVY5L6E1QM442yGFMtulOgg+1asj1w=; b=WkNpJkR1h7Z66oawEbdWS2+ypIJyWyJW2zkJcgQ/PbqYplfee3VpGveH2OkX2RUR39rsQQ T9PCoRkB7B5yrbSx/pbWmdmrHrLlKjRGOSE+oNWRFdymOZb/o2OiDWPIGd3xptgx9vKsF+ DrayLFz0gNOpx2F/8GIh+yD1aJk5MtA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-143-JbAeTytJOpenl25RMLvAHw-1; Fri, 04 Dec 2020 12:04:40 -0500 X-MC-Unique: JbAeTytJOpenl25RMLvAHw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 60EB1800D55; Fri, 4 Dec 2020 17:04:38 +0000 (UTC) Received: from gondolin (ovpn-113-97.ams2.redhat.com [10.36.113.97]) by smtp.corp.redhat.com (Postfix) with ESMTP id ACD005C1C4; Fri, 4 Dec 2020 17:04:25 +0000 (UTC) Date: Fri, 4 Dec 2020 18:04:22 +0100 From: Cornelia Huck To: David Gibson Subject: Re: [for-6.0 v5 12/13] securable guest memory: Alter virtio default properties for protected guests Message-ID: <20201204180422.4a7e8cfb.cohuck@redhat.com> In-Reply-To: <20201204054415.579042-13-david@gibson.dropbear.id.au> References: <20201204054415.579042-1-david@gibson.dropbear.id.au> <20201204054415.579042-13-david@gibson.dropbear.id.au> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Received-SPF: pass client-ip=216.205.24.124; envelope-from=cohuck@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -35 X-Spam_score: -3.6 X-Spam_bar: --- X-Spam_report: (-3.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.496, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: pair@us.ibm.com, brijesh.singh@amd.com, frankja@linux.ibm.com, kvm@vger.kernel.org, "Michael S. Tsirkin" , Richard Henderson , Marcelo Tosatti , david@redhat.com, qemu-devel@nongnu.org, dgilbert@redhat.com, pasic@linux.ibm.com, borntraeger@de.ibm.com, qemu-s390x@nongnu.org, qemu-ppc@nongnu.org, berrange@redhat.com, thuth@redhat.com, pbonzini@redhat.com, rth@twiddle.net, mdroth@linux.vnet.ibm.com, Eduardo Habkost Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Fri, 4 Dec 2020 16:44:14 +1100 David Gibson wrote: > The default behaviour for virtio devices is not to use the platforms normal > DMA paths, but instead to use the fact that it's running in a hypervisor > to directly access guest memory. That doesn't work if the guest's memory > is protected from hypervisor access, such as with AMD's SEV or POWER's PEF. > > So, if a securable guest memory mechanism is enabled, then apply the > iommu_platform=on option so it will go through normal DMA mechanisms. > Those will presumably have some way of marking memory as shared with > the hypervisor or hardware so that DMA will work. > > Signed-off-by: David Gibson > Reviewed-by: Dr. David Alan Gilbert > --- > hw/core/machine.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) Reviewed-by: Cornelia Huck