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 lists1p.gnu.org (lists1p.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 6E880C79F80 for ; Fri, 4 Sep 2026 08:20:01 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1x2P97-0005wh-K2; Fri, 04 Sep 2026 04:19:37 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1x2P95-0005wG-JL for qemu-devel@nongnu.org; Fri, 04 Sep 2026 04:19:35 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1x2P93-0001g4-KP for qemu-devel@nongnu.org; Fri, 04 Sep 2026 04:19:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1788509972; 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=spxozVQA6iSz1FLZsD/Ul/7ecf3JuPqoCoxd76szXFE=; b=YNqTokBw5o7rOGDF2sbW5ZEEWxmda47vtqZ08cSSJqN/lklhBElu++YxXa4IU8YkPOyQ+V l1iqN7ir7uhXDJQuPe/I8LC34ca5RLVVjmt12nqGX+vH/esNqiD2FRjVHz+aqGxMzOOFSL p4oRk9HsGFJeuKM3TVYxBLz08Yr8j7Y= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-661-p1hUJDl3MOCeXBzBjNfHZA-1; Fri, 04 Sep 2026 04:19:28 -0400 X-MC-Unique: p1hUJDl3MOCeXBzBjNfHZA-1 X-Mimecast-MFC-AGG-ID: p1hUJDl3MOCeXBzBjNfHZA_1788509967 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 51D35195399B; Fri, 4 Sep 2026 08:19:27 +0000 (UTC) Received: from redhat.com (headnet03.pony-001.prod.iad2.dc.redhat.com [10.2.32.114]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id F30D71955F70; Fri, 4 Sep 2026 08:19:24 +0000 (UTC) Date: Fri, 4 Sep 2026 09:19:22 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Pierrick Bouvier Cc: qemu-devel@nongnu.org, anjo@rev.ng, Daniel Henrique Barboza , philmd@oss.qualcomm.com, Peter Maydell , Paolo Bonzini , Richard Henderson , Yonggang Luo Subject: Re: [PATCH 00/47] single-binary: implement dynamic filtering for QOM types Message-ID: References: <20260828225901.367438-1-pierrick.bouvier@oss.qualcomm.com> <4b4f77ee-21e9-405e-a1da-21506afa1c5b@oss.qualcomm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <4b4f77ee-21e9-405e-a1da-21506afa1c5b@oss.qualcomm.com> User-Agent: Mutt/2.4.0 (2026-06-19) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: 12 X-Spam_score: 1.2 X-Spam_bar: + X-Spam_report: (1.2 / 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, RCVD_IN_SBL_CSS=3.335, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development 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 Fri, Aug 28, 2026 at 04:13:32PM -0700, Pierrick Bouvier wrote: > On 8/28/2026 3:58 PM, Pierrick Bouvier wrote: > > Now that we can link a single-binary with at least two targets (arm, aarch64), > > we want to make sure that we expose the same set of machines (later devices and > > cpus) than target binaries. For that, we implemented a static filtering based on > > target interfaces that each machine will implement to declare which targets have > > this machine. > > > > However, we discovered that this static filtering is not enough. Indeed, some > > machines and devices do not depend only on target, and their presence can depend > > on Kconfig or host/target combination. Thus, our static approach can't work, and > > we need something more flexible. > > > > The goal of this series is to focus on the filtering mechanism, not on the > > qemu-system binary itself, even though it's included here to give a full picture > > of what we are building. > > > > v3 > > -- > > > > Suggested by Richard, we simply use a callback added to TypeInfo. > > Added full example with a single binary for arm+aarch64, and then > > arm+aarch64+microblaze. > > Also, added scripts/single-binary-compare-cmdline.sh, which compares list of > > cpus, devices and machines between single-binary and original binaries. > > This is what we can use in CI to ensure we correctly tagged all QOM types. > > > > After applying this series, and running > scripts/single-binary-compare-cmdline.sh, you'll see than many devices > are visible for microblaze, and should not. > > microblaze+arm is a more interesting combination than riscv+arm because > riscv has a lot of devices in common with arm. On the opposite, > microblaze has a very reduced set (no virtio, no pci, etc). > > I would like to focus the conversation on how to filter the remaining > types. We could maybe generate something directly from Kconfig output, > so we don't need boilerplate for each CONFIG_X entry. I'm still not clear on why we need to filter the devices at all for a new "qemu-system" binary ? Looking at the device delta listed in your other mail, a large number of those are PCI based. The microblaze machine types don't expose a PCI controller, so those PCI devices are redundant / won't be used with microblaze machines, which is why existing qemu-system-microblaze doesn't link to those devices. The same is true of many of the arm machines too though. Only a subset of arm machines have PCI, but the qemu-system-arm binary still includes and lists all these PCI devices. Users simply can't create a PCI device for the arm machines that lack a PCI controller, or they'll receive an error. Why doesn't this approach extend into the future qemu-system binary ? List everything, and if the user tries to add a device that's not compatible with a machine, then it will simply result in an error. It seems like much less work overall to do no filtering at all, than trying to do per-target filtering which is the wrong granularity to begin with, since the device usability contraints come from the machine rather than the target. With regards, Daniel -- |: https://berrange.com ~~ https://hachyderm.io/@berrange :| |: https://libvirt.org ~~ https://entangle-photo.org :| |: https://pixelfed.art/berrange ~~ https://fstop138.berrange.com :|