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 X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A4A47C433DF for ; Mon, 12 Oct 2020 10:32:07 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 037E220790 for ; Mon, 12 Oct 2020 10:32:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 037E220790 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ilande.co.uk Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:56078 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kRv7e-00038D-32 for qemu-devel@archiver.kernel.org; Mon, 12 Oct 2020 06:32:06 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53032) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kRv5z-0001gf-J1; Mon, 12 Oct 2020 06:30:24 -0400 Received: from mail.ilande.co.uk ([2001:41c9:1:41f::167]:49472 helo=mail.default.ilande.uk0.bigv.io) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kRv5t-0006t7-NW; Mon, 12 Oct 2020 06:30:22 -0400 Received: from host86-158-109-18.range86-158.btcentralplus.com ([86.158.109.18] helo=[192.168.1.65]) by mail.default.ilande.uk0.bigv.io with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1kRv5r-0004Y3-Je; Mon, 12 Oct 2020 11:30:16 +0100 To: Eduardo Habkost , qemu-devel@nongnu.org References: <20201006220647.GR7303@habkost.net> From: Mark Cave-Ayland Message-ID: Date: Mon, 12 Oct 2020 11:30:11 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.3.1 MIME-Version: 1.0 In-Reply-To: <20201006220647.GR7303@habkost.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 86.158.109.18 X-SA-Exim-Mail-From: mark.cave-ayland@ilande.co.uk Subject: Re: Purpose of QOM properties registered at realize time? X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on mail.default.ilande.uk0.bigv.io) Received-SPF: pass client-ip=2001:41c9:1:41f::167; envelope-from=mark.cave-ayland@ilande.co.uk; helo=mail.default.ilande.uk0.bigv.io X-detected-operating-system: by eggs.gnu.org: No matching host in p0f cache. That's all we know. X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Maydell , qemu-riscv@nongnu.org, qemu-arm@nongnu.org, qemu-ppc@nongnu.org, Paolo Bonzini , "Daniel P. Berrange" , John Snow Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 06/10/2020 23:06, Eduardo Habkost wrote: > Hi, > > While trying to understand how QOM properties are used in QEMU, I > stumbled upon multiple cases where alias properties are added at > realize time. > > Now, I don't understand why those properties exist. As the > properties are added at realize time, I assume they aren't > supposed to be touched by the user at all. If they are not > supposed to be touched by the user, what exactly is the purpose > of those QOM properties? > > For reference, these are the cases I've found: (cut) > -- > hw/misc/mac_via.c=1011=static void mac_via_realize(DeviceState *dev, Error **errp) > hw/misc/mac_via.c:1028: object_property_add_alias(OBJECT(dev), "irq[0]", OBJECT(ms), This one was me trying to work out how to wire up an IRQ from a child device embedded within the macio device - I'll send a patch to remove it shortly. ATB, Mark.