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 7A208CF9C6B for ; Tue, 24 Sep 2024 08:46:36 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1st1B5-0006sy-ES; Tue, 24 Sep 2024 04:45:47 -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 1st1B1-0006sE-W9 for qemu-devel@nongnu.org; Tue, 24 Sep 2024 04:45:46 -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 1st1Az-0003dL-8t for qemu-devel@nongnu.org; Tue, 24 Sep 2024 04:45:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1727167540; 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=XMBhLuLKAGj/L7UU0MwXAH+HXBYid+z2XzbTcY25Lsg=; b=IJ7YjwG8zJrOe9pCN6Ml3AVPuHcYv80Hjfk6mtC24yfGZo3dGBYuB6oFKIt6R8imuPOJZL upsdmb7r9b6xN1SEBe6BTzVpkgmuQWi+37uMRz0w/K2DT6WAPmr8pGFzsZlDJh5/Cy6GWN dn9VIqxP8JsutO+1MuWhNpWOBMsWz+A= Received: from mx-prod-mc-04.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-688-zR08SeqEMxaz-JVnv2xlbg-1; Tue, 24 Sep 2024 04:45:35 -0400 X-MC-Unique: zR08SeqEMxaz-JVnv2xlbg-1 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (unknown [10.30.177.12]) (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-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 1BCAF19030BD; Tue, 24 Sep 2024 08:45:34 +0000 (UTC) Received: from redhat.com (unknown [10.39.194.29]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7706119560AE; Tue, 24 Sep 2024 08:45:29 +0000 (UTC) Date: Tue, 24 Sep 2024 10:45:25 +0200 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Manos Pitsidianakis Cc: qemu-devel@nongnu.org, Cleber Rosa , John Snow , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Paolo Bonzini , Alex =?utf-8?B?QmVubsOp?= e , Gustavo Romero , Peter Maydell , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Pierrick Bouvier , Richard Henderson Subject: Re: [PATCH v2] Add -build-info and -build-info-json CLI arguments Message-ID: References: <20240923-feature-build-info-cli-v2-1-66b3462f16a1@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/2.2.12 (2023-09-09) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 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: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.144, 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_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=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, Sep 23, 2024 at 10:09:32PM +0300, Manos Pitsidianakis wrote: > Hello Daniel, > > On Mon, 23 Sep 2024 19:45, "Daniel P. Berrangé" wrote: > > On Mon, Sep 23, 2024 at 09:05:24AM +0300, Manos Pitsidianakis wrote: > > > Add -build-info and -build-info-json CLI arguments for human and machine > > > readable output of build/compile-time configuration data. The source for > > > this data is the meson generated config-host.h. > > > > > > This information is mainly of interest to developers and other folk who > > > deal with many different builds of QEMU and need a way to properly > > > differentiate them. > > > > > > Because there's always the chance someone will want to consume an > > > interface programmatically, also add a -json option that does the same > > > but outputs a machine-readable JSON object. > > > > This turns our build system configuration information into a > > defacto public API, and while its using JSON, it isn't yusing > > QAPI. > > > > To some degree we leak our build system config names externally > > because the "if" stanzas in the QAPI schema get copied into the > > docs. > > > > Overall though I don't think we should be exposing this build > > config infomation externally. We've had many times, particularly > > with testing, where people have wanted to access CONFIG_XXX info > > about a QEMU binary, but IIRC we've always steered people towards > > querying for the actual feature they want, rather than looking > > at CONFIG_XXX settings. > > > > ie, look a query-audiodevs to discover what audio baxckends are > > built-in, don't look for CONFIG_XXX settings related to audio. > > If there are gaps in information we can query from QMP, we should > > aim to close those gaps. > > > > IOW, I don't think we should expose this build info info in either > > human readable or machine readable format. > > QAPI/QMP is not the perspective of this patch, this is for people who use > custom-built (i.e. not from a distro) binaries and want to be able to > identify how it was built. Launching a binary to query stuff is > unnecessarily complex for this task, and the info is not generally > interesting to the API consumers as you said. Launching QEMU to talk QMP is our defined public API for querying anything about the capabilities of QEMU. We're worked hard to get away from providing ad-hoc ways to query QEMU from the command line and going back to that is not desirable. It may be slightly more complicated, but not by very much. 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 :|