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 0279EE66887 for ; Sun, 24 Nov 2024 14:24:48 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tFDWk-000188-Bo; Sun, 24 Nov 2024 09:23:54 -0500 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 1tFDWf-00017s-SD for qemu-devel@nongnu.org; Sun, 24 Nov 2024 09:23:49 -0500 Received: from mout02.posteo.de ([185.67.36.66]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tFDWQ-0002bO-Ns for qemu-devel@nongnu.org; Sun, 24 Nov 2024 09:23:37 -0500 Received: from submission (posteo.de [185.67.36.169]) by mout02.posteo.de (Postfix) with ESMTPS id 4D3C9240101 for ; Sun, 24 Nov 2024 15:23:28 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=posteo.net; s=2017; t=1732458208; bh=2MJGTHtwie0rwB93olR2WoDlfQqyQr9af8HZtlELRSU=; h=Message-Id:To:Subject:From:Date:MIME-version:Content-type: Content-Transfer-Encoding:From; b=fPBbj6xCnYnEFvy3vO6WbeET/cQMYaxZZUywaWh/j7PThUJTS93INe/xGUeyZffZk YevAMLex2Ipcbyu6Tju7eV8AuuBsh7gKByQafdfJy1/EYW8V0cKH3aANnabud7VpZ6 cdGObhZdmCcq6uMXBzT+GBTZCJ4J4dxEcu3D7qp9teYB5feKKnBZGRLa7QANCJnu3P L9fuOqGF3ShPG7+j7VANfRpQLQO1jDFv6Euzma8xoXDaO0GXJO3IJXZF0SytSAy9nL sv0WagX6ySDwP4PsxwdQlbczJjMuFSVHrsCiGHz2GBXW92Yi69L4jTUinm18c5zgNE kTIKFXy1cqqAA== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 4Xx9zz0DxCz6tn4 for ; Sun, 24 Nov 2024 15:23:26 +0100 (CET) Message-Id: To: qemu-devel@nongnu.org Subject: Onboarding QEMU Firmware Configuration to other machines From: Anne Macedo Date: Sun, 24 Nov 2024 14:22:29 +0000 MIME-version: 1.0 Content-type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=185.67.36.66; envelope-from=retpolanne@posteo.net; helo=mout02.posteo.de X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Hello! How should one port fw_cfg to other QEMU machines? Context: - I found a possible bug on the Debian builds for Raspberry Pi 4 that is only triggered when I try to launch it on QEMU; - I wrote an issue on systemd (I thought it had something to do with logind) and they requested me to only fill bugs if they show up on the upstream. - I tried baking systemd with mkosi – however, to test with mkosi and qemu, it uses fw_cfg [1] which seems specific to the virt machine on ARM. - Opened an issue [2] and started working on that [3] However, I still don't understand exactly how fw_cfg works. My current understanding is that it is a device that, when connected some memory mapping will happen on the guest so that it can access this memmap. TL;DR which steps should I take to onboard fw_cfg to machines such as raspi4b? Thanks! Anne [1] https://github.com/systemd/mkosi/blob/6c33859a1b445e0bff19d9e7f28158140893a3e4/mkosi/config.py#L456 [2] https://gitlab.com/qemu-project/qemu/-/issues/2695 [3] https://gitlab.com/retpolanne/qemu/-/commit/86fca16555385c3685b7a1489a9cfaa255e148cf