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 84261C433EF for ; Mon, 14 Feb 2022 10:35:30 +0000 (UTC) Received: from localhost ([::1]:57122 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nJYhd-0000Ld-IF for qemu-devel@archiver.kernel.org; Mon, 14 Feb 2022 05:35:29 -0500 Received: from eggs.gnu.org ([209.51.188.92]:45520) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nJYcv-00069b-1m for qemu-devel@nongnu.org; Mon, 14 Feb 2022 05:30:37 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:53931) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nJYcs-0007ns-Pa for qemu-devel@nongnu.org; Mon, 14 Feb 2022 05:30:36 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1644834633; 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=1tO2NWITAnce+5vRCgppP+B+Icvby3c0gmVwtt+hV0w=; b=ek/iPh84YnDYDnWYqJCZ/+pjsKusyqeNClD/SHsqhr6JlmxA2zSBqOgydr9Pxok5PzoRO/ mQJU9qdKtbtE2DfIdoqrJpxKjEcv3trw/Fufm8DGZgTbvsJnkzDP59K2Xo2P4o/h+528o4 OHCS6rKCQbdnUWShUxozQVd7SSX5Po0= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-86-9hXoYG-8NyWwpgUOY2DNKA-1; Mon, 14 Feb 2022 05:30:30 -0500 X-MC-Unique: 9hXoYG-8NyWwpgUOY2DNKA-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 32BBF1091DA2; Mon, 14 Feb 2022 10:30:29 +0000 (UTC) Received: from redhat.com (unknown [10.39.192.189]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 263847B6F7; Mon, 14 Feb 2022 10:30:20 +0000 (UTC) Date: Mon, 14 Feb 2022 10:30:18 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Igor Mammedov Subject: Re: [PATCH v4 4/4] hw/i386/sgx: Attach SGX-EPC objects to machine Message-ID: References: <20220205124526.500158-1-f4bug@amsat.org> <20220205124526.500158-5-f4bug@amsat.org> <20220207093752.7503b6cb@redhat.com> <20220214065857.GA5015@yangzhon-Virtual> <20220214092107.56d3f300@redhat.com> MIME-Version: 1.0 In-Reply-To: <20220214092107.56d3f300@redhat.com> User-Agent: Mutt/2.1.5 (2021-12-30) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit 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: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Yang Zhong , Jean-Philippe Brucker , "Michael S. Tsirkin" , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , qemu-devel@nongnu.org, Ani Sinha , Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Feb 14, 2022 at 09:21:07AM +0100, Igor Mammedov wrote: > On Mon, 14 Feb 2022 14:58:57 +0800 > Yang Zhong wrote: > > > On Mon, Feb 07, 2022 at 09:37:52AM +0100, Igor Mammedov wrote: > > > On Sat, 5 Feb 2022 13:45:26 +0100 > > > Philippe Mathieu-Daudé wrote: > > > > > > > Previously SGX-EPC objects were exposed in the QOM tree at a path > > > > > > > > /machine/unattached/device[nn] > > > > > > > > where the 'nn' varies depending on what devices were already created. > > > > > > > > With this change the SGX-EPC objects are now at > > > > > > > > /machine/sgx-epc[nn] > > > > > > > > where the 'nn' of the first SGX-EPC object is always zero. > > > > > > yet again, why it's necessary? > > > > > > Igor, Sorry for delay feedback because of Chinese New Year holiday. > > > > This series patches are to fix below issues I reported before, > > https://lists.nongnu.org/archive/html/qemu-devel/2021-11/msg05670.html > > > > Since the /machine/unattached/device[0] is used by vcpu and Libvirt > > use this interface to get unavailable-features list. But in the SGX > > VM, the device[0] will be occupied by virtual sgx epc device, Libvirt > > can't get unavailable-features from this device[0]. > > > > Although patch 2 in this series already fixed "unavailable-features" issue, > > I've seen patches on libvirt fixing "unavailable-features" in another way > without dependence on /machine/unattached/device[0]. > see: > https://www.mail-archive.com/libvir-list@redhat.com/msg226244.html > > > this patch can move sgx virtual device from /machine/unattached/device[nn] > > to /machine/sgx-epc[nn], which seems more clear. Thanks! > > with those patches device[0] becomes non issue, and this patch also becomes > unnecessary. > I don't mind putting sgx-epc under machine, but that shall be justified > somehow. A drawback I noticed in this case is an extra manual > plumbing/wiring without apparent need for it. This is effectively questioning why we have a QOM hierarchy with named devices at all. IMHO we don't need to justify giving explicitly named nodes under QOM beyond "this is normal QOM modelling", and anything under '/unattached' is subject to being fixed in this way. 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 :|