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.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 B6C89FF885A for ; Tue, 28 Apr 2026 07:49:26 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.1295410.1572062 (Exim 4.92) (envelope-from ) id 1wHdBZ-0000HY-7M; Tue, 28 Apr 2026 07:48:49 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 1295410.1572062; Tue, 28 Apr 2026 07:48:49 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1wHdBZ-0000HR-3L; Tue, 28 Apr 2026 07:48:49 +0000 Received: by outflank-mailman (input) for mailman id 1295410; Tue, 28 Apr 2026 07:48:48 +0000 Received: from mx.expurgate.net ([195.190.135.10]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1wHdBY-0000HL-8c for xen-devel@lists.xenproject.org; Tue, 28 Apr 2026 07:48:48 +0000 Received: from mx.expurgate.net (helo=localhost) by mx.expurgate.net with esmtp id 1wHdBX-007BUw-3Y for xen-devel@lists.xenproject.org; Tue, 28 Apr 2026 09:48:47 +0200 Received: from [10.42.69.5] (helo=localhost) by localhost with ESMTP (eXpurgate MTA 0.9.1) (envelope-from ) id 69f06654-2eae-0a2a0a5409dd-0a2a45059f60-40 for ; Tue, 28 Apr 2026 09:48:46 +0200 Received: from [52.101.56.7] (helo=BN1PR04CU002.outbound.protection.outlook.com) by tlsNG-c201ff.mxtls.expurgate.net with ESMTPS (eXpurgate 4.56.1) (envelope-from ) id 69f0665d-aaa8-0a2a45050019-3465380733bd-3 for ; Tue, 28 Apr 2026 09:48:46 +0200 Received: from CH7PR03MB7860.namprd03.prod.outlook.com (2603:10b6:610:24e::14) by BN9PR03MB6204.namprd03.prod.outlook.com (2603:10b6:408:101::21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9846.26; Tue, 28 Apr 2026 07:48:44 +0000 Received: from CH7PR03MB7860.namprd03.prod.outlook.com ([fe80::f5ba:35df:1c9f:b343]) by CH7PR03MB7860.namprd03.prod.outlook.com ([fe80::f5ba:35df:1c9f:b343%4]) with mapi id 15.20.9846.025; Tue, 28 Apr 2026 07:48:44 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" Authentication-Results: eu.smtp.expurgate.cloud; dkim=pass header.s=selector1 header.d=citrix.com header.i="@citrix.com" header.h="From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=E6e84rqZK2HeKCPLoCPjafeM1dPfXU2Wf3lZrRiN4dyOoXZpDA8gkax8//YOWNY4Jm8jR88UhiVOlE6JVVHsb5KvBtvAT8D7oP5GntIM64oMZGeX8eWNXG3NP/3WE4k2aKRmDZaZdIYjxjNeHy+OphEQJB3l+FqO9tnLhjNIsGATlK12UgrnYFZtKrBPYlDlM/Hm735f/RNuOTW8+29ejkEbGc5GeebLqVg0xtcTL9Ku79h7YZfY2h92ixyCJFeViYS5lYb63ewtAMES0CeYui+zAbOLu8Q1QgUTz297wm55ygtYYTtR9zfA9vqq5zBrHlmzEircpEExVsx8MTJEvA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=t5LjEDnCnKB+aJUEQ/u4vjV15DYk3BNPjC1GMqMTxMY=; b=YaAZuoizsBHsdFwlz31H0Ns6/Rvh2VmFwl6dsRVO+SWr+4gFmkgPmxqJFvM7VpuAf+imzTsVpuSGZIS4umIdKVJbmF9HlSSOeqlkZmcD9f0I7R3j6sAjG5YlRI15bIbL9mpusag8R2MpmHgls3zAFGkhQajzgPakzXBBMUHfo/Jr69GHyWBF9w1U9MdOvhuvcrJgFquoY6bB5J25EUxmbLyRdoZXSUR49V8JU/yqYdFi8tfwInwaiECGQuNZYtypy6CrWWDmJWymo9dkPntBvc7AHOxbTR49ZjnUgaBbE5uTLvFSli4zZBVXHj7clMsuDL5DyabvAgngdU87VZkJGQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=citrix.com; dmarc=pass action=none header.from=citrix.com; dkim=pass header.d=citrix.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=citrix.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=t5LjEDnCnKB+aJUEQ/u4vjV15DYk3BNPjC1GMqMTxMY=; b=YTQrsln/vCVjdEsRvlj67EpfiIMtd4IWBKyJBwyue4HqmHbzyvYVe4tKDgCs2V1ffDzyNbfQvXVhL7TqY7ifBkA0YGGXQebyWmo4dqQsCg8OM/roKLf45FM+5aumPuQneWPda6O64K5ZrD0Lw83nDdZGknH/hYgJ0TR4ceZnNQY= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=citrix.com; Date: Tue, 28 Apr 2026 09:48:41 +0200 From: Roger Pau =?utf-8?B?TW9ubsOp?= To: Thierry Escande Cc: xen-devel@lists.xenproject.org, Jan Beulich , Andrew Cooper , Anthony PERARD , Michal Orzel , Julien Grall , Stefano Stabellini , Juergen Gross Subject: Re: [PATCH 00/17] Q35 initial support for HVM guests Message-ID: References: <20260313163455.790692-1-thierry.escande@vates.tech> Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20260313163455.790692-1-thierry.escande@vates.tech> X-ClientProxiedBy: BN9P220CA0016.NAMP220.PROD.OUTLOOK.COM (2603:10b6:408:13e::21) To CH7PR03MB7860.namprd03.prod.outlook.com (2603:10b6:610:24e::14) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH7PR03MB7860:EE_|BN9PR03MB6204:EE_ X-MS-Office365-Filtering-Correlation-Id: 83eb3cea-0ab0-45c9-7126-08dea4fa9277 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|366016|1800799024|56012099003|22082099003|18002099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:CH7PR03MB7860.namprd03.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(376014)(366016)(1800799024)(56012099003)(22082099003)(18002099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?SUU0VGRYMFlPL3AxRDUvS2xtMS93cUEzeTcwUnhBNHdmWjd6aU9oNXAzemRw?= =?utf-8?B?eEpON0p1ZXBqOFhja1MvWHpOcklHSVVqaE5pTU4yOStjYW4rc1dadGNKNXVh?= =?utf-8?B?SU5rSW55eStXdnMyUGlxaGVpazR5V0hOTk9kQ2xKQzRMYWdTNUZHWER4eGdt?= =?utf-8?B?eFJlYll4UWF1SzQ4c0FoUmEwU3lqRGNGMmh1dTdVV1NFcXAvZEI3ZllwUVE5?= =?utf-8?B?NkxPdm9PamNzWWh2dnR1eWZ2bUFCN3k5SVozejd2NjdqNERCTy9EWTVpK3Jr?= =?utf-8?B?NzBpdDYzWm9DU1R6L2J2UmhETFlPQk8xRUw1Y0xGZ01TZW5EV3hMSnJPOG9G?= =?utf-8?B?ZUxFNU1nRzR3d1dtT2wrdG9EOE5laytDdG16MzZQMkJEd3N3ZU1leVcwcGQ5?= =?utf-8?B?S01hOXludFhNUVNhY3JXQjArbjJkUGlnRVptaXdadE9mYitsN1IzdXBhaG9w?= =?utf-8?B?MmZ2eEcvRmU0T01mT3VVajdodlM0Q21STXFBVzhZVzA3N1JNakNCU2hCQ2M5?= =?utf-8?B?SnRMMzQxY2Q0VFRQeWwrRXpHVXFOMjZXV0NYOFhSSzloVWFFOWcvQnNmYWJF?= =?utf-8?B?alM1TUJoN2dDZndMeGtteDlHQnJ1K3Jpa0lYVlU5ekNjanNlU2p0Y25tdzZN?= =?utf-8?B?RW52eVVuTlZqSWd1T0FJNkRuUjJpNUVqcmxMRzVsYkZnNHpDdWJ2ZzUzOVVD?= =?utf-8?B?dlBnN01McVZEZm1VWHpLbTZWbkZBVjFkVGhNaTJmREdWc3E0YXpyWWlZNjdq?= =?utf-8?B?cU14NHZDOGxidHV6MTJ2ZkVBWFIvNDJyR2oyeUFYM2pjak11VUcvYWx5cHA4?= =?utf-8?B?QXNRa09XVm4yQjFBQk1GaWRlSXVLdlFCc0p6OXY3L2ZiYk0rQmcyRFlucUxY?= =?utf-8?B?Z3FacGlvbCtLMStaSHFIa005TDcyY0VqdG1tTWJYVlRnZUw1UCs3S0RQN3Fr?= =?utf-8?B?RGE4TVlkVVdLL01tdngzSSsxUnNyR24ybjc4VnpYVWg5SFpsZVVUdVU2RUM5?= =?utf-8?B?RWdZVk9QdlRjT0JoKzVVMlh5TzRGckVyRkJFOHNtMHhPZTBBRngvcjJSM1pQ?= =?utf-8?B?Y1ZWd0o4Qml0WXg1NzNIWWlIUHdXcjFGV1NyQk16ZmZhYk5pTC9pZVFxenZy?= =?utf-8?B?b3oydlJrQXVMMVNicWVGV25DbE0rcWZ2TVNrdTF4SlZyYklRcVRaaWdsbFAv?= =?utf-8?B?OTVHaFZMQS8rYVpYRjc2dmNMR1cvVE5jTnF4Y3Y4ZGpsaTk1ZEcveDRWK3ph?= =?utf-8?B?em5oTklZZEREN2NjK3dkbm5FTWNZUFYyTDVrN1g4Nlk1SWI1N1JTMkd3aTBz?= =?utf-8?B?MmluZ0M4NXZrZVBoSm9YLy9OMnFGaDQyQjc5UzZNSnp6L3lkYW4xMFZPVzJv?= =?utf-8?B?dzlZSFBXajNOK2REQ0FHUUkyZ1NXRnliSktYT1Q5Ty85cXlHTXkzR2djMkg4?= =?utf-8?B?OEF2UDFhYUhWc05haWFhNVhOYWJOODc2cnAyNnU0cmZuU0tIUkIvZ2g4YVRU?= =?utf-8?B?a3lzZWZCVzQvQlEwa0haNDhXczhkUEo0QVpaM2lRSkJHMmRVYU1TOE95SE5H?= =?utf-8?B?czF5c1FZaGsrRzlFNHJpbmR3UkRWd0xwRzVmTzhMc0U5NExWekM4RGJNMnR2?= =?utf-8?B?bFFWc1F2ZWtqQnZ2UVRRNXk2WXBCRzFuL0F4czF2dlQ5QVVUQTBuZDZBdnBZ?= =?utf-8?B?aUlmcmtGdDkyTDV6MXlaYmdjNGlPWTZONXdaR2hBMmhXRkpCVFZrUDFEY2pS?= =?utf-8?B?cEtKYjFiamxMSHM4YVF5bW9IMTdLZHExczJZUkV5R1VWb045aVJiSk9wdUgz?= =?utf-8?B?THg4MGJlMktEdUt5RCtRY3VPTnBOcGlyK0xCQXdHVXNIMmIxSjIvRnhKQ0s1?= =?utf-8?B?OTZ2bFVSU3BoaUVKWnBLR3E5ZVJvQmYwYUdRWlk0RjExZzZSd2lrQmdxV1dX?= =?utf-8?B?V3AyUWRvTzR5OWZueCtJN1NZc2Z5UXZHRENkZ1dEcElmT3RIU0tXc2lUUG5s?= =?utf-8?B?V1Bpb2JwRWxSb3pubTdpczUxK2I2WFg1ZDlZcnZ4Rk9HNkpWTWlzcEZvZFdE?= =?utf-8?B?ZVlvemh4Z3JTUzFWVHhkdEx2UWRrQm9mU2xIc3JNL3k4MU1PSmZRTFh1U0Vi?= =?utf-8?B?Si9FSDFKcGF1QnBEM2tTNmgzRUZNQVBVN1JJYjBNenpiMU4xMER2NGR2bm9t?= =?utf-8?B?Wkh2ZHV0VDBSZ212MmpQU2VGRE5iR3hiWTdGb3JwY1pNQTE0cEZOQnZndUdH?= =?utf-8?B?K2Noa2pJZEdmRVgvRlNRYWhUdVVPaGdDb3ZJVmNtd0wrd3R1L2cyQnBUcEEy?= =?utf-8?B?Wi8vc2Z3amxISDE0a3RDcjBYQ0xZZlZDTldERGNpRlE4SWFnTzdXUT09?= X-OriginatorOrg: citrix.com X-MS-Exchange-CrossTenant-Network-Message-Id: 83eb3cea-0ab0-45c9-7126-08dea4fa9277 X-MS-Exchange-CrossTenant-AuthSource: CH7PR03MB7860.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Apr 2026 07:48:44.1878 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 335836de-42ef-43a2-b145-348c2ee9ca5b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: vrmdLBiHJa9C9UxeqDy4LO3OWAnar2G+sL8ye+YXFefA/rP3FlPoGcxJBougOoXjfscAniEBI4pTjs+lfnZtSQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN9PR03MB6204 X-purgate-ID: tlsNG-c201ff/1777362526-E0FA2443-F201F1E8/0/0 X-purgate-type: clean X-purgate-size: 2096 On Fri, Mar 13, 2026 at 04:35:01PM +0000, Thierry Escande wrote: > This series introduces initial Q35 chipset support for HVM guests, based on the > patchset at [1] by Alexey Gerasimenko. > > Basic support means that this patchset allows to start an HVM guest that > emulates a Q35 chipset via Qemu and implements access to PCIe extended > configuration space for such devices emulated by Qemu. > > Support for PCIe device passthrough is not implemented yet. This is planned but > implies modifications in the hypervisor and the firmwares, mainly for the > support of multiple PCI buses. Why do you need multi bus support to expose PCIe capabilities? I'm not seeing the relation between those two. You could still expose a single bus on the MCFG table. > In order to create a Q35 guest, a new domain config option has been added, > named 'device_model_machine'. Possible values are: > - "i440" - i440 emulation (default) > - "q35" - emulate a Q35 machine > > If the option is omitted it defaults to "i440", not impacting existing domain > configuration files. > > DSDT files for Q35 and i440 are largely similar so the existing file dsdt.asl > has been split with i440 and q35 specific parts put in seperated files. > > The PCIe MMCONFIG area is configured by hvmloader and its base address and size > are set in Xen using a new pair of hypercalls HVMOP_get|set_ecam_space. I guess I will see how that looks like in the series, but the setting of the ECAM region would better be done by the toolstack. Setting it in hvmloader is possibly not the best placement, because it doesn't run for PVH guests (and we will want ECAM support for PVH at some point), and there's also a vague plan/intention to get rid of hvmloader even for HVM guests eventually. > Access > to the MMCONFIG area from a guest is trapped by Xen and transfered to the > emulator as XEN_DMOP_IO_RANGE_PCI ioreq type. Thanks for doing this bit, IIRC from when this was last posted this was the biggest shortcoming of the series when originally submitted. Thanks, Roger.