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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id B3EB4C4332F for ; Wed, 14 Dec 2022 11:31:50 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1p5Pyu-0002Kj-Ua; Wed, 14 Dec 2022 06:31:28 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p5Pyl-0002JM-LL for qemu-devel@nongnu.org; Wed, 14 Dec 2022 06:31:15 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p5Pyj-00062O-Tx for qemu-devel@nongnu.org; Wed, 14 Dec 2022 06:31:15 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1671017472; h=from:from:reply-to: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=4J58rsfRVQad+uxiP3edDoD9MOaylfdRXUM/Lyi50Ro=; b=XXsUGzArLMAeyyJ3nqjLNYexprQX6Os9nDKpF1OSLG2CHat5C3tM7D8/SOejkjGtv8EI7X g9fhS2QIax8KCvxTY+7KOwm3Oe5VFsAFzwMTibBCfcLdIEfcqKDLQZI23kJIcnLqDSlhHJ 7jZwjnk4GZNb/q5Q6Evk0l2IRfWdpGM= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-510-vKl1k4tGOD2YgPFO3Zx5-g-1; Wed, 14 Dec 2022 06:31:09 -0500 X-MC-Unique: vKl1k4tGOD2YgPFO3Zx5-g-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 0B66A1871CDB; Wed, 14 Dec 2022 11:31:09 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.128]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2FF3F79A1; Wed, 14 Dec 2022 11:31:08 +0000 (UTC) Date: Wed, 14 Dec 2022 11:31:03 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: James Bottomley Cc: qemu-devel@nongnu.org, Stefan Berger , Markus Armbruster Subject: Re: [PATCH] tpm: add backend for mssim Message-ID: References: <4780481659602f92fffacac66e7dca41ad2787c4.camel@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/2.2.7 (2022-08-07) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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_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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Mon, Dec 12, 2022 at 05:06:05PM -0500, James Bottomley wrote: > On Mon, 2022-12-12 at 15:47 +0000, Daniel P. Berrangé wrote: > > Copy'ing Markus for QAPI design feedback. > > > > On Sat, Dec 10, 2022 at 12:10:18PM -0500, James Bottomley wrote: > [...] > > > +## > > > +# @TPMmssimOptions: > > > +# > > > +# Information for the mssim emulator connection > > > +# > > > +# @host: host name or IP address to connect to > > > +# @port: port for the standard TPM commands > > > +# @ctrl: control port for TPM state changes > > > +# > > > +# Since: 7.2.0 > > > +## > > > +{ 'struct': 'TPMmssimOptions', > > > +  'data': { > > > +      'host': 'str', > > > +      'port': 'str', > > > +      'ctrl': 'str' }, > > > +  'if': 'CONFIG_TPM' } > > > > We don't want to be adding new code using plain host/port combos, > > as that misses extra functionality for controlling IPv4 vs IPv6 > > usage. > > > > The existing 'emulator' backend references a chardev, but I'm > > not especially in favour of using the chardev indirection either, > > when all we should really need is a SocketAddress > > > > IOW, from a QAPI design POV, IMHO the best practice would be > > > >  { 'struct': 'TPMmssimOptions', > >    'data': { > >        'command': 'SocketAddress', > >        'control': 'SocketAddress' }, > >    'if': 'CONFIG_TPM' } > > > > > > The main wrinkle with this is that exprssing nested struct fields > > with QemuOpts is a disaster zone, and -tpmdev doesn't yet support > > JSON syntax. > > > > IMHO we should just fix the latter problem, as I don't think it > > ought to be too hard. Probably a cut+paste / search/replace job > > on the chanmge we did for -device in: > > > >   commit 5dacda5167560b3af8eadbce5814f60ba44b467e > >   Author: Kevin Wolf > >   Date:   Fri Oct 8 15:34:42 2021 +0200 > > > >     vl: Enable JSON syntax for -device > > > > This would mean we could use plain -tpmdev for a local instance > > > >    -tpmdev mssim,id=tpm0 \ > >     -device tpm-crb,tpmdev=tpm0 \ > > > > but to use a remote emulator we would use > > > >     -tpmdev "{'backend': 'mssim', 'id': 'tpm0', > >               'command': { > >                  'type': 'inet', > >                  'host': 'remote', > >                  'port': '4455' > >                }, > >               'control': { > >                  'type': 'inet', > >                  'host': 'remote', > >                  'port': '4456' > >                }}" > > > > (without the whitepace/newlines, which i just used for sake of > > clarity) > > Just on this, might it not be easier for the commandline to do what > gluster does? just use the '.' as a separator and subqdict extraction, > so you'd specify > > -tpmdev mssim,id=tpm0,command.type=inet,command.host=remote,command.port=4455,control.type=inet,control.host=remote,control.port=4456 > > With the added bonus that X.type could be defaulted to inet and > control.host could follow command.host and so on? These days, we have a policy of not tyring to map nested data onto the flat QemuOpts. This has been done in several areas and we've ended up with a mess of ever so slightly different impls each with their own flaws. This is why our preferred approach these days is to add support for JSON syntax to enable non-flat config. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|