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 A4C9DC7EE23 for ; Mon, 8 May 2023 10:29:10 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pvy6Y-0000kx-L3; Mon, 08 May 2023 06:28:30 -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 1pvy6V-0000kW-I2 for qemu-devel@nongnu.org; Mon, 08 May 2023 06:28:28 -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 1pvy6S-0002hM-Af for qemu-devel@nongnu.org; Mon, 08 May 2023 06:28:26 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1683541703; 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=8CSQU7q8v2C6dLNLtEXDHV7t6O6HfpA/FaJMOy1UMp8=; b=hc5bRbrbfhKpxYPCxYz3uripxxGLHddg5mktG8Y45gGVbsT04H693zcIJaJPVHWZThngiL LonnSwVelEB90/ztqamr0DpPNQUuEV6Dn2OUAIQSPMSYXUrQi2bcsLLvWjcj23a7nqrU5J fCJkYS0PBMCNJXf+6dVIoCKXK67cHaQ= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-500-oH3ts2o7NxqldR8FIdXNTQ-1; Mon, 08 May 2023 06:28:22 -0400 X-MC-Unique: oH3ts2o7NxqldR8FIdXNTQ-1 Received: by mail-wm1-f71.google.com with SMTP id 5b1f17b1804b1-3f41efd04dfso9214305e9.1 for ; Mon, 08 May 2023 03:28:21 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683541701; x=1686133701; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=8CSQU7q8v2C6dLNLtEXDHV7t6O6HfpA/FaJMOy1UMp8=; b=d91BZ5yY8LlrP+lr/fbmgBNNhBbGudHnIgbloYRCms7/efKonwgmGofmFxbYVJV39V /ddZHxTKiGb+BhvluCOJ3lv9oFjqiPH2Xa1Ir0+UtL/ZPlWNav/W878f4K1RKwtdsQ8t Pz/2r9DZMOC5mAh0Ts2lLr//M8bkJB4L2lFEHehdgOAeqV8Y5EqGkSofvit8MWH93pov ttcx+D2yyQMq7iSaZYkfW6jLReTP/CsLMlyj/nrnm4FmIMt/tispboLLoiTHj2pf8ht+ SRnUZIrTls1KB7Nsvr7PibzWwpH1SsKFwp/TPtfW3RiMqRZChS2bjNIkGzkh5h5DQldO XR1A== X-Gm-Message-State: AC+VfDxeYMdjJVJBhKMbvgZ4gVRQzK5Vf7krFBVJCZkQVibzcnQe9Urd QuMXsmGyZ6bWu5dvWEUqLSvMcHNUahK7lkz7S2SGC31tNsLc5We+SvnPtYhFA+UeMya7E1aD02p rCiTCC7764EFxKNY= X-Received: by 2002:a05:600c:2213:b0:3f4:1cd8:3e99 with SMTP id z19-20020a05600c221300b003f41cd83e99mr4114594wml.28.1683541700824; Mon, 08 May 2023 03:28:20 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ6LrBXlhbK3WGJmJVumBMNzxItSpD7PJFq96Z8VFTd52yyQJFrTO8g+YMyK8+sVcofw6wnWog== X-Received: by 2002:a05:600c:2213:b0:3f4:1cd8:3e99 with SMTP id z19-20020a05600c221300b003f41cd83e99mr4114584wml.28.1683541700500; Mon, 08 May 2023 03:28:20 -0700 (PDT) Received: from redhat.com ([31.187.78.15]) by smtp.gmail.com with ESMTPSA id d6-20020a056000114600b00306344eaebfsm10914024wrx.28.2023.05.08.03.28.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 08 May 2023 03:28:20 -0700 (PDT) Date: Mon, 8 May 2023 06:28:15 -0400 From: "Michael S. Tsirkin" To: Michael Tokarev Cc: QEMU Developers , Marcel Apfelbaum , Markus Armbruster Subject: Re: missing boot rom: is it really a fatal error? Message-ID: <20230508062407-mutt-send-email-mst@kernel.org> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Received-SPF: pass client-ip=170.10.133.124; envelope-from=mst@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_H2=-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 On Sun, May 07, 2023 at 08:56:23PM +0300, Michael Tokarev wrote: > Hi! > > In old good world ;), there was qemu which didn't require boot roms to be present > for all devices for which bootrom file is defined, missing rom was just a warning. > But this changed in 2014, 9 years ago, with this commit: > > commit 178e785fb4507ec3462dc772bbe08303416ece47 > From: Marcel Apfelbaum > Date: Mon, 27 Oct 2014 19:34:41 +0200 > Subject: [PATCH] hw/pci: fixed error flow in pci_qdev_init > > Verify return code for pci_add_option_rom. > > where inability to load rom file started being treated as an error. > Up until now I didn't even know about this change, until today when someone bugged > me about non-working qemu on debian, due to missing network boot roms (this a > packaging issue due to me being unaware of the above change). > > What is the reason to require boot roms to be present and throw an error if not? > > I'm about to revert that old change on debian, to make it just a warning instead > of an error (the code is different now, but the same principle applies), - because > I dislike dependencies which are useless 99.9% of the time and are trivial to > install when actually needed. > > Thanks, > > /mjt > I advise against it. If you boot guest on a system with boot rom not installed you will not be able to migrate to a system with boot rom installed. why not? because we don't know how big to make the rom BAR. And users will not discover until much much later after they have painted themselves into a corner. -- MST