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 B8FBDEB64DA for ; Thu, 20 Jul 2023 19:36:41 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qMZRe-0003u5-0R; Thu, 20 Jul 2023 15:36:14 -0400 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 1qMZRb-0003rX-6w for qemu-devel@nongnu.org; Thu, 20 Jul 2023 15:36:11 -0400 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 1qMZRZ-0007Y1-LO for qemu-devel@nongnu.org; Thu, 20 Jul 2023 15:36:10 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1689881769; 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=gBMnzG4MebFIf16BpkbQyP0Yw4tKPK9x1cMKc+CNT+k=; b=SOv/3Cgz26a4G9cq11pQzRv2Jrymh15zTRrQuMP9saA5bYAunC92ATezJOacOLT2PTUN0p T9O+aPZeU8fyhU+piz7QW1v7smNMpyro/MSI7e22lmE/9peGoK5lK10IXiE44/gcDhV1vi G7DQEXQvKgs4j9amLTQR7Sev+bz1vlU= Received: from mimecast-mx02.redhat.com (66.187.233.73 [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-296-sTKFDoLzPx6EJnvZT2Gw4g-1; Thu, 20 Jul 2023 15:36:04 -0400 X-MC-Unique: sTKFDoLzPx6EJnvZT2Gw4g-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 093EB3C160E4; Thu, 20 Jul 2023 19:36:03 +0000 (UTC) Received: from localhost (unknown [10.39.194.253]) by smtp.corp.redhat.com (Postfix) with ESMTP id 61A3740C6F4C; Thu, 20 Jul 2023 19:36:02 +0000 (UTC) Date: Thu, 20 Jul 2023 15:36:01 -0400 From: Stefan Hajnoczi To: Stefano Garzarella Cc: Alex =?iso-8859-1?Q?Benn=E9e?= , qemu-devel@nongnu.org, virtio-dev@lists.oasis-open.org, slp@redhat.com, mst@redhat.com, marcandre.lureau@redhat.com, viresh.kumar@linaro.org, takahiro.akashi@linaro.org, erik.schilling@linaro.org, manos.pitsidianakis@linaro.org, mathieu.poirier@linaro.org Subject: Re: [virtio-dev] [RFC PATCH] docs/interop: define STANDALONE protocol feature for vhost-user Message-ID: <20230720193601.GI210977@fedora> References: <20230704123600.1808604-1-alex.bennee@linaro.org> <3ogh7u3ezp7vlrp3ticquoajgsnpnglplm44osrsd7gvxv2lyn@g22qgf4vwgp5> <87o7krg0sn.fsf@linaro.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="PJgjM68U1AKlFxoJ" Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org --PJgjM68U1AKlFxoJ Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Jul 07, 2023 at 12:27:39PM +0200, Stefano Garzarella wrote: > On Tue, Jul 04, 2023 at 04:02:42PM +0100, Alex Benn=E9e wrote: > >=20 > > Stefano Garzarella writes: > >=20 > > > On Tue, Jul 04, 2023 at 01:36:00PM +0100, Alex Benn=E9e wrote: > > > > diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.= rst > > > > index 5a070adbc1..85b1b1583a 100644 > > > > --- a/docs/interop/vhost-user.rst > > > > +++ b/docs/interop/vhost-user.rst > > > > @@ -275,6 +275,21 @@ Inflight description > > > >=20 > > > > :queue size: a 16-bit size of virtqueues > > > >=20 > > > > +Backend specifications > > > > +^^^^^^^^^^^^^^^^^^^^^^ > > > > + > > > > ++-----------+-------------+------------+------------+ > > > > +| device id | config size | min_vqs | max_vqs | > > > > ++-----------+-------------+------------+------------+ > > > > + > > > > +:device id: a 32-bit value holding the VirtIO device ID > > > > + > > > > +:config size: a 32-bit value holding the config size (see ``VHOST_= USER_GET_CONFIG``) > > > > + > > > > +:min_vqs: a 32-bit value holding the minimum number of vqs support= ed > > >=20 > > > Why do we need the minimum? > >=20 > > We need to know the minimum number because some devices have fixed VQs > > that must be present. >=20 > But does QEMU need to know this? >=20 > Or is it okay that the driver will then fail in the guest if there > are not the right number of queues? I don't understand why min_vqs is needed either. It's not the front-end's job to ensure that the device will be used properly. A spec-compliant driver will work with a spec-compliant device, so it's not clear why the front-end needs this information. Stefan --PJgjM68U1AKlFxoJ Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmS5jKAACgkQnKSrs4Gr c8iL2QgAqCc6gx0y20MWAVkqX4M5cONVtaHUBQz26ZTaU20ipQ1qS4HYsgGW67hX fthNJsVS3gGpAhkjOf3bWMB5s20sjAEdifjqZe8C2HL2AxRJsNYBZwH/btA3aWbC 0w7uxLUcXv1ccqsE4CMp+DPIHOnKwA5ewlbg7P04ya4kNjzx5WM2EMJhlJ9vbybx +7UuPukQDV/TG3yBJOz61wCQQ/ABt0njwxXJakMVyRj0O6aHbZDPs09ibFmc9jDW O+35GNYVSdvN3/cd8J6Vc2ikJ4q+jEK0/E8jbh6+jc7OOQ3BKnluKhwkGYvouSDK Ia7ziZJnl7n7fzghOOdSpPu8/a63RQ== =dGKO -----END PGP SIGNATURE----- --PJgjM68U1AKlFxoJ--