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=-12.2 required=3.0 tests=BAYES_00,DATE_IN_PAST_24_48, DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 5DEB3C433F5 for ; Fri, 3 Sep 2021 13:10:19 +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 E7AD260F42 for ; Fri, 3 Sep 2021 13:10:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org E7AD260F42 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:57624 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mM8xW-0001Ww-4t for qemu-devel@archiver.kernel.org; Fri, 03 Sep 2021 09:10:18 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:47312) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mM8vt-000756-0H for qemu-devel@nongnu.org; Fri, 03 Sep 2021 09:08:37 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:59409) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mM8vq-0001LP-Dv for qemu-devel@nongnu.org; Fri, 03 Sep 2021 09:08:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1630674513; 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: in-reply-to:in-reply-to:references:references; bh=t6ngGaEtZC1Sw+hJnB2wnbTqJr373XZc/kHpy6ebEjk=; b=ZzSJyasq6J7MP8Er8XmASIF0ZwgYQKw1aSvn7A092BGC3RAxcmRMA2sXO4QLm/ttZpcchC olPF4lu2Kk8xGsWJLt84xNpZAPId6KSV++JKp5dwbneu+DeG5f5PSrzFz5uH9yJe5nhER6 XJwWR6Opr82t4vn4RPxmPldUB4aMFdY= 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-220-l9lw_RJjMYmhfG2ihTD9NQ-1; Fri, 03 Sep 2021 09:08:32 -0400 X-MC-Unique: l9lw_RJjMYmhfG2ihTD9NQ-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 D985B6D5C3; Fri, 3 Sep 2021 13:08:30 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-112-13.ams2.redhat.com [10.36.112.13]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 843D75C1C5; Fri, 3 Sep 2021 13:08:27 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id B18C511380CC; Wed, 1 Sep 2021 16:14:10 +0200 (CEST) From: Markus Armbruster To: Michael Roth Subject: Re: [RFC PATCH v2 12/12] i386/sev: update query-sev QAPI format to handle SEV-SNP References: <20210826222627.3556-1-michael.roth@amd.com> <20210826222627.3556-13-michael.roth@amd.com> Date: Wed, 01 Sep 2021 16:14:10 +0200 In-Reply-To: <20210826222627.3556-13-michael.roth@amd.com> (Michael Roth's message of "Thu, 26 Aug 2021 17:26:27 -0500") Message-ID: <87tuj4qt71.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, DATE_IN_PAST_24_48=1.34, DKIMWL_WL_HIGH=-0.392, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-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: Tom Lendacky , "Daniel P . =?utf-8?Q?Berran?= =?utf-8?Q?g=C3=A9?=" , Eduardo Habkost , kvm@vger.kernel.org, "Michael S . Tsirkin" , Connor Kuehl , Eric Blake , James Bottomley , qemu-devel@nongnu.org, "Dr . David Alan Gilbert" , Dov Murik , Brijesh Singh , Paolo Bonzini , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , David Gibson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Michael Roth writes: > Most of the current 'query-sev' command is relevant to both legacy > SEV/SEV-ES guests and SEV-SNP guests, with 2 exceptions: > > - 'policy' is a 64-bit field for SEV-SNP, not 32-bit, and > the meaning of the bit positions has changed > - 'handle' is not relevant to SEV-SNP > > To address this, this patch adds a new 'sev-type' field that can be > used as a discriminator to select between SEV and SEV-SNP-specific > fields/formats without breaking compatibility for existing management > tools (so long as management tools that add support for launching > SEV-SNP guest update their handling of query-sev appropriately). Technically a compatibility break: query-sev can now return an object that whose member @policy has different meaning, and also lacks @handle. Matrix: Old mgmt app New mgmt app Old QEMU, SEV/SEV-ES good good(1) New QEMU, SEV/SEV-ES good(2) good New QEMU, SEV-SNP bad(3) good Notes: (1) As long as the management application can cope with absent member @sev-type. (2) As long as the management application ignores unknown member @sev-type. (3) Management application may choke on missing member @handle, or worse, misinterpret member @policy. Can only happen when something other than the management application created the SEV-SNP guest (or the user somehow made the management application create one even though it doesn't know how, say with CLI option passthrough, but that's always fragile, and I wouldn't worry about it here). I think (1) and (2) are reasonable. (3) is an issue for management applications that support attaching to existing guests. Thoughts? > > The corresponding HMP command has also been fixed up similarly. > > Signed-off-by: Michael Roth > --- > qapi/misc-target.json | 71 +++++++++++++++++++++++++++++++++--------- > target/i386/monitor.c | 29 +++++++++++++---- > target/i386/sev.c | 22 +++++++------ > target/i386/sev_i386.h | 3 ++ > 4 files changed, 95 insertions(+), 30 deletions(-) > > diff --git a/qapi/misc-target.json b/qapi/misc-target.json > index 3b05ad3dbf..80f994ff9b 100644 > --- a/qapi/misc-target.json > +++ b/qapi/misc-target.json > @@ -81,6 +81,49 @@ > 'send-update', 'receive-update' ], > 'if': 'TARGET_I386' } > > +## > +# @SevGuestType: > +# > +# An enumeration indicating the type of SEV guest being run. > +# > +# @sev: The guest is a legacy SEV or SEV-ES guest. > +# @sev-snp: The guest is an SEV-SNP guest. > +# > +# Since: 6.2 > +## > +{ 'enum': 'SevGuestType', > + 'data': [ 'sev', 'sev-snp' ], > + 'if': 'TARGET_I386' } > + > +## > +# @SevGuestInfo: > +# > +# Information specific to legacy SEV/SEV-ES guests. > +# > +# @policy: SEV policy value > +# > +# @handle: SEV firmware handle > +# > +# Since: 2.12 > +## > +{ 'struct': 'SevGuestInfo', > + 'data': { 'policy': 'uint32', > + 'handle': 'uint32' }, > + 'if': 'TARGET_I386' } > + > +## > +# @SevSnpGuestInfo: > +# > +# Information specific to SEV-SNP guests. > +# > +# @policy: SEV-SNP policy value > +# > +# Since: 6.2 > +## > +{ 'struct': 'SevSnpGuestInfo', > + 'data': { 'policy': 'uint64' }, > + 'if': 'TARGET_I386' } > + > ## > # @SevInfo: > # > @@ -94,25 +137,25 @@ > # > # @build-id: SEV FW build id > # > -# @policy: SEV policy value > -# > # @state: SEV guest state > # > -# @handle: SEV firmware handle > +# @sev-type: Type of SEV guest being run > # > # Since: 2.12 > ## > -{ 'struct': 'SevInfo', > - 'data': { 'enabled': 'bool', > - 'api-major': 'uint8', > - 'api-minor' : 'uint8', > - 'build-id' : 'uint8', > - 'policy' : 'uint32', > - 'state' : 'SevState', > - 'handle' : 'uint32' > - }, > - 'if': 'TARGET_I386' > -} > +{ 'union': 'SevInfo', > + 'base': { 'enabled': 'bool', > + 'api-major': 'uint8', > + 'api-minor' : 'uint8', > + 'build-id' : 'uint8', > + 'state' : 'SevState', > + 'sev-type' : 'SevGuestType' }, > + 'discriminator': 'sev-type', > + 'data': { > + 'sev': 'SevGuestInfo', > + 'sev-snp': 'SevSnpGuestInfo' }, > + 'if': 'TARGET_I386' } > + > > ## > # @query-sev: [...]