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 26584C77B7F for ; Mon, 8 May 2023 10:38:34 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pvyFa-0005NO-SR; Mon, 08 May 2023 06:37:51 -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 1pvyFT-0005Mj-4x for qemu-devel@nongnu.org; Mon, 08 May 2023 06:37:43 -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 1pvyFR-0005dd-Ii for qemu-devel@nongnu.org; Mon, 08 May 2023 06:37:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1683542260; 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=HaQy9fJQzBpLmqDD9N1u58teUu+qZNPnimfoMdI90eg=; b=WyH54UgtbG+q5rdp0H/V1aQUjZDXQyWM28x99SxfXQxN+zOGpexO5zX+SXg8yHHD9lQjBY V5SD2+HmP/f08Txw/FG3ND8wAUVL0lcbFS9EIc8P/LfYAspY5+lj8VnMV6Nn3rUC2dmgq9 vSZDo/D7B0lYoUXYdavmU+fu8xAPgGg= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-581-52sfzWL7NXS_7kAT4vtLCg-1; Mon, 08 May 2023 06:37:38 -0400 X-MC-Unique: 52sfzWL7NXS_7kAT4vtLCg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 006032999B2A; Mon, 8 May 2023 10:37:38 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.192.121]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D17682026D16; Mon, 8 May 2023 10:37:37 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 58D6B21E6924; Mon, 8 May 2023 12:37:36 +0200 (CEST) From: Markus Armbruster To: "Michael S. Tsirkin" Cc: Michael Tokarev , QEMU Developers , Marcel Apfelbaum Subject: Re: missing boot rom: is it really a fatal error? References: <20230508062407-mutt-send-email-mst@kernel.org> Date: Mon, 08 May 2023 12:37:36 +0200 In-Reply-To: <20230508062407-mutt-send-email-mst@kernel.org> (Michael S. Tsirkin's message of "Mon, 8 May 2023 06:28:15 -0400") Message-ID: <87sfc7jehb.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 Received-SPF: pass client-ip=170.10.129.124; envelope-from=armbru@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, 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 "Michael S. Tsirkin" writes: > 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. For what it's worth: we know when property "romsize" is set. > And users will not discover until much much later after they have > painted themselves into a corner.