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=-5.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 0E798C433B4 for ; Tue, 6 Apr 2021 09:49:50 +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 9C6B6613BC for ; Tue, 6 Apr 2021 09:49:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9C6B6613BC 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]:56048 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lTiLE-0002WH-Iu for qemu-devel@archiver.kernel.org; Tue, 06 Apr 2021 05:49:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:51040) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lTiJF-0001dY-7g for qemu-devel@nongnu.org; Tue, 06 Apr 2021 05:47:46 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:55337) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lTiJ4-0008RW-6z for qemu-devel@nongnu.org; Tue, 06 Apr 2021 05:47:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617702451; 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:in-reply-to:in-reply-to: references:references; bh=PNvaWNPL2Y1WPPsqporgBhyuhMu+0f6ltnCNLMWNAYg=; b=cKOitJm50YeIdxS2VIeyzSFndxiE1XNk86Jj0pWHLlPYwvM3P51uqEk2EzY0KmSa3RgN4L A0eUe1FN1tVV4tsUI8la0Vk5DuPVFCxACgZ4MLyi/dGPaY59IgsTkFfZjNWKKXZS2KLm4O VY62NG3kYjqh9aez+MgIeGdb0Z4vbmA= 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-12-GcLkASTEMr-wqxfzpKz5aQ-1; Tue, 06 Apr 2021 05:47:27 -0400 X-MC-Unique: GcLkASTEMr-wqxfzpKz5aQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C500783DD22 for ; Tue, 6 Apr 2021 09:47:26 +0000 (UTC) Received: from redhat.com (ovpn-114-172.ams2.redhat.com [10.36.114.172]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 8894019635; Tue, 6 Apr 2021 09:47:15 +0000 (UTC) Date: Tue, 6 Apr 2021 10:47:12 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Igor Mammedov Subject: Re: [PATCH 2/6] pci: introduce apci-index property for PCI device Message-ID: References: <20210315180102.3008391-1-imammedo@redhat.com> <20210315180102.3008391-3-imammedo@redhat.com> MIME-Version: 1.0 In-Reply-To: <20210315180102.3008391-3-imammedo@redhat.com> User-Agent: Mutt/2.0.5 (2021-01-21) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 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 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: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 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_LOW=-0.7, RCVD_IN_MSPIKE_H4=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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: jusual@redhat.com, qemu-devel@nongnu.org, laine@redhat.com, mst@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Mar 15, 2021 at 02:00:58PM -0400, Igor Mammedov wrote: > In x86/ACPI world, linux distros are using predictable > network interface naming since systemd v197. Which on > QEMU based VMs results into path based naming scheme, > that names network interfaces based on PCI topology. > > With itm on has to plug NIC in exactly the same bus/slot, > which was used when disk image was first provisioned/configured > or one risks to loose network configuration due to NIC being > renamed to actually used topology. > That also restricts freedom to reshape PCI configuration of > VM without need to reconfigure used guest image. > > systemd also offers "onboard" naming scheme which is > preferred over PCI slot/topology one, provided that > firmware implements: > " > PCI Firmware Specification 3.1 > 4.6.7. DSM for Naming a PCI or PCI Express Device Under > Operating Systems > " > that allows to assign user defined index to PCI device, > which systemd will use to name NIC. For example, using > -device e1000,acpi-index=100 > guest will rename NIC to 'eno100', where 'eno' is default > prefix for "onboard" naming scheme. This doesn't require > any advance configuration on guest side to com in effect > at 'onboard' scheme takes priority over path based naming. > > Hope is that 'acpi-index' it will be easier to consume by > management layer, compared to forcing specific PCI topology > and/or having several disk image templates for different > topologies and will help to simplify process of spawning > VM from the same template without need to reconfigure > guest NIC. > > This patch adds, 'acpi-index'* property and wires up > a 32bit register on top of pci hotplug register block > to pass index value to AML code at runtime. > Following patch will add corresponding _DSM code and > wire it up to PCI devices described in ACPI. You've illustrated usage & benefits with NICs, but IIUC, this feature is wired up for any PCI device. Are you aware of any usage of this feature for non-NIC devices ? 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 :|