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 4C009C44500 for ; Thu, 22 Jan 2026 08:24:23 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.1210476.1522128 (Exim 4.92) (envelope-from ) id 1vipys-0001fC-Fp; Thu, 22 Jan 2026 08:23:54 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 1210476.1522128; Thu, 22 Jan 2026 08:23:54 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1vipys-0001f5-Cj; Thu, 22 Jan 2026 08:23:54 +0000 Received: by outflank-mailman (input) for mailman id 1210476; Thu, 22 Jan 2026 08:23:53 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1vipyr-0001ez-8D for xen-devel@lists.xenproject.org; Thu, 22 Jan 2026 08:23:53 +0000 Received: from CY3PR05CU001.outbound.protection.outlook.com (mail-westcentralusazlp170130007.outbound.protection.outlook.com [2a01:111:f403:c112::7]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id adeca11c-f76b-11f0-b15e-2bf370ae4941; Thu, 22 Jan 2026 09:23:51 +0100 (CET) Received: from CH7PR03MB7860.namprd03.prod.outlook.com (2603:10b6:610:24e::14) by PH0PR03MB6938.namprd03.prod.outlook.com (2603:10b6:510:16c::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9542.9; Thu, 22 Jan 2026 08:23:47 +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 15.20.9542.008; Thu, 22 Jan 2026 08:23:46 +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" X-Inumbo-ID: adeca11c-f76b-11f0-b15e-2bf370ae4941 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=uzX47nrBqRlxBqmqq9r67p5WRr+8GiTBMjndYSgqehzcHrHgtOVCDHjChHSOuR6MRHrMxHT+rBk5v2jPvO7Rq/NgJLmWwCy/ZaKpbW2UUHnvLxPfEisR9j/SjFLq0mqNoSypTm7YFsClyXPbsAS8ac+5JUtRCStLz9xKd/cZHsCEs33Drlj9nT61cLqM/Vyqse55YH037pTH+/O0h1MzvEH27goeI5Yovoc7vl3B+uB6XXCmUN4v+9df4HF0D8TnjikbNt93XDJj1nQXf5LGs2gOa3/YDuiXAfIT8PDEuuoyJCPR2LfYNi3rMvdJndUKXJh9HvbjPZ/T7q7oKKQEXQ== 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=jWx11zkhJal/3cG430UB5J5NPVmKeBxVAY+JCjZJie8=; b=yKn6A5lYb89WYaOiie9gqumaLsmJt1AYEPuvusqFuQl72udQzcuEz5EhZp1uOK8m7rEOmipDV27khGShjGCWKI1Nxv7GjYNE/Rv0/X3MjPxUCgJSK0eiY9adD0nClz/AmfYlYd0O2++ub8HR9nvasajj0sJ4ko1xXzum56p+ucq+cKwnMYhWZU5DSlcxe3hPK0Fw4uFyMY0qb/TqZ4OqW4ThuUjLdQNSfwI8WFW5Pp0Igl/sGQu4t0yhNaGKR8XYhqLJD5uCjsu7jWySqb1BjRiq00veAqWt9ZY1fDpN9IGrltIHslwK4rgJxhs1OS8NrXKWUYHOwLIaJyYI12l1gA== 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=jWx11zkhJal/3cG430UB5J5NPVmKeBxVAY+JCjZJie8=; b=Ytc+BReW8KGJxas4GBPDW0VsEkcj2VF26zEkCjF83lZKKpIVe9qtMTg2SuMO/YK8FmfGsSsGbFu736iVlKWFYSpDnSIE7pt4NeYCF35jgw3llmvouNcxdT7eUG1xJk07vfWj5OiPv82R7bel7g3XN+QW1+hb9wFTaPxSs96hcrs= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=citrix.com; Date: Thu, 22 Jan 2026 09:23:43 +0100 From: Roger Pau =?utf-8?B?TW9ubsOp?= To: Jan Beulich Cc: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org, James Dingwall , Juergen Gross , Stefano Stabellini , Oleksandr Tyshchenko , Jason Andryuk Subject: Re: [PATCH] Partial revert "x86/xen: fix balloon target initialization for PVH dom0" Message-ID: References: <20260120140648.25977-1-roger.pau@citrix.com> <634471a1-1185-4644-aeea-7891e62bc1f0@suse.com> Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <634471a1-1185-4644-aeea-7891e62bc1f0@suse.com> X-ClientProxiedBy: MA2P292CA0009.ESPP292.PROD.OUTLOOK.COM (2603:10a6:250:1::14) To CH7PR03MB7860.namprd03.prod.outlook.com (2603:10b6:610:24e::14) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH7PR03MB7860:EE_|PH0PR03MB6938:EE_ X-MS-Office365-Filtering-Correlation-Id: 93d73caf-3410-4bf6-182d-08de598f900d X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|1800799024|366016; X-Microsoft-Antispam-Message-Info: =?utf-8?B?SHRiamgvSUNwYURRVXR5UjMwVEx1NlJaQ1RyTW5EWEw2NHJSZmFKK2p0cjA3?= =?utf-8?B?a0VPdzN5d0lFVTdQRVp4MXNlNGRUeDNXQUswcURIQWRkTWR6bldXOU5JZE5o?= =?utf-8?B?aWhqb3JoNFVjMWthYlJxSTZwQlF2L3haNldxeURPQm13SXVXZjdLVmI5QzRC?= =?utf-8?B?dXNiQlVwV0dwZm5OU1FrOGYxT3c1MlVDVXdLcjFwY21qdlFSaWFkNyt4dVg2?= =?utf-8?B?VUZ5M3hGdWtzZHNPVnVoemRockxCMVpmTXVTNnl4NHlEVUY0L2hlK1g1QUxL?= =?utf-8?B?SUFhNGRqZUt5SUVKV283Z2VvZWFJSFJNQWtvYm00Y2V1a2Q2cWtGcjd3S2c1?= =?utf-8?B?SFF4UGVBU1h1YzNldml0SlFXYmg3M1J5TlhGQWtBUzZic1duMUJ2VW9ERm9Z?= =?utf-8?B?OG42cEJrMWw1S1l2ZVBDTXZaUTE0eGhYU0h3OHNXVzhlaUY5RVRUL1l6dHVm?= =?utf-8?B?VjMzb3VuRWkzVDZodmsrUndtWDdTc3psMm9hQjhSMG1yQW15Y0dXOHZ3dXVC?= =?utf-8?B?VjNIYlNqY3o5SUdJTDVTUTYxVjU4UG5TQUd5T2dZSXZmQmNRNkpiVGxsK0lS?= =?utf-8?B?ZTNmSk9aaWVLU29zK1RPQkQ1emo5MnBiRlBBZGJrVC9VK3lDNG5VajBNeVdV?= =?utf-8?B?Zm50bHo0RHRkRzRpS3pyR0xNeXYvNmNzSkhpVzVQR090UkxObkh1MTZhQkFY?= =?utf-8?B?Y3BDSFlUbDZIR1VKUWJXVFBPYS9lZGViTVczQWprM1pTWmF1M3hDMTRlMnVC?= =?utf-8?B?N2tIbVYxVERkamNVNzlOOGZ5YzhyS3hjYUJhVTJ3VktVdEZxYUJkM28xT2pp?= =?utf-8?B?Vzh5eTVGQWRlRDIvSFk2V3l4ODFVVmVFV3h5MFBKeTZ5cyt3ZmFJenJXZi9K?= =?utf-8?B?L2p4Njg5ZzBENmtma0oreDZkVTZUcjVZVWtSUUM0d3lodE5pYXo4VXpDRE9G?= =?utf-8?B?MHh3UTdxbUhtQytFQS8rOUwrUmhhSFZVZEtTR3VNTS9NalRDc0RpRHRYSnRl?= =?utf-8?B?RWZEVGFBa1FOOVpSK1hFK044T0RIdXBOSGxqcGh2SnJPaUtyZ1lmRWJmUFd6?= =?utf-8?B?UkdJWFFBWTRtSkFZZDRMU1dSdzZBdWphN2N1QVJsN29scnJ6dmFBdG1Kc2lq?= =?utf-8?B?NWl0Z0M2OWFsZHRCNVNaR3pNZjc1eXdZM1U5NXp5WG5xamwwNSt3VXI0Syti?= =?utf-8?B?Z1p4WktxRHR1YVlGdGFaQ1lsYTQrZnNmdk9aZXY1SVJPTUVJdFBhUVVqbHVP?= =?utf-8?B?ZVd1OFNvTUpmVGJjcnB1dDlTZWovYmJsbHRWRTh1dXBCTVVLeWxMSS9VZDA1?= =?utf-8?B?SlZBZTY5eFVtbDlHb3lRSlUveEd0bFVPUnFMSm05a05mTDBoUzg2MXJIVXUz?= =?utf-8?B?Sml4L09zZ3dNUWhUWmpCcTFiOUxtWDdwS2pHZUMrZ2RndHFrQ1ZLYVZsMWhM?= =?utf-8?B?eksxZWdCaHRNT3BwY0xwaGFzKy92a3dRVGtmRjdtVHNJMkhsdWVSR0kydndm?= =?utf-8?B?Um5NaUFtNXE5ZUFTVnYzcEpnby8yYVl1Y0p1NDc0ODBkT0paSmhaODl6SzhG?= =?utf-8?B?d3FCZlVDTWVkdDQ3UzRNTi9UbjBHb3diTmlkR2cwTWJSVkVQUU9Da3VwZlRr?= =?utf-8?B?L1E0TWUvbjYyblYrMll4amxtNC9Ed0hMMjJFdEFwd0d4SEZSUHVneUEyZUJl?= =?utf-8?B?K1M4VC85L3pJTjl4N3lDOTZNbHk2bTBpUmUrbHh0d2dhOVIzS21aMndFLzQy?= =?utf-8?B?MnExcFhzTlROOGh5TkxPcDkzNDlLRDlRSWxQQWpsZ3A3U0I1bE1DYlBzRWJi?= =?utf-8?B?czE0L21mdW1WSE5NV0VJUnpIdTJDTDM2akFTRFlmWkg1Z2JzSzlxQWdWWU5J?= =?utf-8?B?Z1QxU0l6RFlMeTFpcHhkSllyNUU5b1daMFc3UCthVThUaEZ5U0RjUnFoVlV2?= =?utf-8?B?bW1tdURPaEYwNTg4UU9rVjJtYSs4UTk4RTl4QUxycFlmNmtjdGxhMTFSSGVM?= =?utf-8?B?NjV6ME5IN045ajV1Z2tPRnNjQm01ZjlMN05tbUwrZVZIdkh3LzN6SzNRblht?= =?utf-8?B?MEthRlpVZG5VSmhCc0NudklPRFFMeWVmNFpTRTUzQ1dydWRiRW5nY3Y4OTMy?= =?utf-8?Q?BF5M=3D?= 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)(1800799024)(366016);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?cW9kdWpjcXBJZk5kMks5UUZIYkRrOWw3QXdxMzBVcVdvNnJ2VjB6MHlyZWRO?= =?utf-8?B?MGp1NkVPOHJDcXRWL3Fnbkl1UVBsWis2MW50dFlQUFBvWGJjMk5JR04yTkhZ?= =?utf-8?B?dlJKTkR2UHVDMXA1SWY5NVlQdWdYZ25POVY2UExOcXdDOU1hdmV2RlFjVWg1?= =?utf-8?B?TWZZeG5ZQVRVZ2ZQOVNsd2NEK2M1NENlUVh3R3A3clFVVDVXTWFSUHFGRXpK?= =?utf-8?B?b2E3eWNLQ2lTMlVzeEpTVmd2TCtwSFRtcTM4Z2wweksrM0pEa21LRzBFQ0s5?= =?utf-8?B?d3dQQjJPM2xzaFhZV0pRSHF5QlZCVXhHeEtISmVkZVJraTVvYy9aWmQzalhU?= =?utf-8?B?L0ErVERYYmVwQnYwR0FvQm1CekJQRTAzcUVZdWxrbHBzUDUrUEM5a1Fwa2wx?= =?utf-8?B?b1BYVW5uR2JBRVNzcHVXNzJzZEZlMnJYbU54RU41V2g1dFo0WVNZZjc0MEFY?= =?utf-8?B?QjF1N3A5K0dBWUkyVnQ5ZWRVWEtSb2YrVThaaWhjcUZVQ3RkNHdySFU0L1dw?= =?utf-8?B?Zm9xMHg0azJvWjJrMVFETmVYTmtranpSVEJ6QjVEbE5tNXp2bkg0ZWRiMWVS?= =?utf-8?B?UXBxZXB5aXZOWlVCaktmL1Vsa25UdkJCUmRhckJjbGRMa1V0RUV1M3R5bXc0?= =?utf-8?B?UDl0cUMxbzFVMlFJRmwwbnV6Z09RSHNaQVhyNVJTWjduc25NZUhCTk9lVUcw?= =?utf-8?B?Rk93Y1MyR0taOGw0b2xLdDQ0amRxd0FGZklzSitXSC9sWkFGTDRuR1BoR3po?= =?utf-8?B?ME1LOExFNTVoZkF5M1pCOEJQazBscVk3VFgrV3E2YUhUN1M3VmRMU2ZCQmlU?= =?utf-8?B?SjFZVHdXeUZ5Zmh5QVhYZHlWQS9GM1IvRjlZZEovVW5qaDBONUh3UlBzMkhi?= =?utf-8?B?MGdRV3ZTbGxyQ1ZjbmRoUUVHM2hUN1BXMGgyeEczSVdyWWNncEFOeHZjSGRS?= =?utf-8?B?QmEwTkN1OHRPYVltVHA2bXdTaWdyRm9KYm80ZnRMeGZiTUtHQit6MUVoeDVV?= =?utf-8?B?U2x3Nk5rNEdjNWhFdkUrWHpsSnVOTEJPKzR6bndrekpxOUNWaHh1YkJtcFdD?= =?utf-8?B?QURwdk1KckY3NkVuS0V0UnNjWU8xQW1SbmlzWXMwU1hmYy9iTEhMd3ErK0hQ?= =?utf-8?B?QWtxSytiL1k4OW5rWmthMWNUWkxlcXF1RlI3b3ozeWFWUzY2d0p5WDVIcjhG?= =?utf-8?B?ekk0QUZyNExmcWxzbDVhU3RFTzNudXZYenV4cGtUR0s0VzYrUGd1d01yN1Z1?= =?utf-8?B?ZU8wbm9UM09tK05NZ2tYTGRPU3R5d1Q0ZzF4Qyt4K0JiNmVJckhhRFAwcnpM?= =?utf-8?B?RVcwSjFMSTJGOG1yVGorTFhtWHlTSSs4enZoVWJ4LzJBUTRKUkJ4SzUwVW5E?= =?utf-8?B?RUpnYllRRkMwVFNKNHlEM0ZQdUtWS2FRR1BxdkpDai9ZNjdTUmM5TjgrZHFm?= =?utf-8?B?dThncmhOVGpsdkl3dkVBTVY3bnA4YXdQeEhpclpCUVpHb0tWck9WUktwU2xS?= =?utf-8?B?ckRDUFFFRndLcWhNYjJhN0dwZ1NNVTIzUGdmemFSL3ljQUVJNkNSeXhTNDB3?= =?utf-8?B?a29GL053aHoySGMwYjI3cnEyVHlYeWY4SU1kN1dlNGV0OXpxc0NUVEtKNWVq?= =?utf-8?B?OEEvV2J4bDFqc2YxYUFnempIY1RaakJYT0Q2WDJsNUt4NHRqVW91b3U4NEFt?= =?utf-8?B?dGdieDNlTzh5elZzOVJLdHQ4MUtURmJUSGtsVE5IVU85T0xldTJzeG1ZWEEv?= =?utf-8?B?SEtkY3M2eXZpRGZtVXg4VW10L1h6cHVQbXZiNWppWVVLYThoZ3lkMTVlZmUx?= =?utf-8?B?T1oyZUY5MlFkdFh4RHl3NE1iS2R2VUtjaGd5RUhFWjg1dUFQMTRQVUpreVR2?= =?utf-8?B?dThYRHY4MFRWdnpoSkdHeVU3d0psbVRZNUVESUkxTERRVmhRNHJOcGwzWGgw?= =?utf-8?B?eWpLVmNza1ZRWE5WZkdGd05UN2NGZ1J3bzN0Y3ErSFlsUlg2MzhVZG1pbGFo?= =?utf-8?B?NkZIb09Gb3Y0RHI0bWFMRXo3MHg1RVVlczdTTW4vT01qMkN4amJzRHpRdTNI?= =?utf-8?B?WXNkOGE0NHVNUE93S2M1RnNJWnNuQ2E3SzhOanFaQTIvZzlPeVFvRkVqS3h1?= =?utf-8?B?ZDhNMEFuNHZMU3BoblBxb0hsMGZvUW1MNWV0aFBCOWZQTFpmeDMvZFZZQTJ3?= =?utf-8?B?Z01aVVJYZWtQbmdKKzhpdmdVemlnOTlIMWVxQXROdjJFYnVVbDYxSDJKNjVp?= =?utf-8?B?eWJnUWZYQ2ZzQkJjY2trSTh2S0lZdnVEMzNqOVAzV1o2bGFqa211aEFYM1dL?= =?utf-8?B?TUh6WWRpWG5mQVdHWGJTY0hCb3RXcTlweFlVWFlaQVlyeGpRalh1dz09?= X-OriginatorOrg: citrix.com X-MS-Exchange-CrossTenant-Network-Message-Id: 93d73caf-3410-4bf6-182d-08de598f900d X-MS-Exchange-CrossTenant-AuthSource: CH7PR03MB7860.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Jan 2026 08:23:46.7696 (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: qTEcWNEgdpiBgoCWRQyBVBVZBpFp6yvjXQTp3zH+w3IaaLqk6MqoV1B7PAosU+xiEQAACiRYNSj+HtKXuqproA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR03MB6938 On Thu, Jan 22, 2026 at 08:17:22AM +0100, Jan Beulich wrote: > On 21.01.2026 18:49, Roger Pau Monné wrote: > > --- a/drivers/xen/balloon.c > > +++ b/drivers/xen/balloon.c > > @@ -724,7 +724,8 @@ static int __init balloon_add_regions(void) > > static int __init balloon_init(void) > > { > > struct task_struct *task; > > - unsigned long current_pages; > > + unsigned long current_pages = 0; > > With this, ... > > > @@ -732,8 +733,13 @@ static int __init balloon_init(void) > > > > pr_info("Initialising balloon driver\n"); > > > > - current_pages = xen_pv_domain() ? min(xen_start_info->nr_pages, max_pfn) > > - : get_num_physpages(); > > + if (xen_initial_domain()) > > + current_pages = HYPERVISOR_memory_op(XENMEM_current_reservation, > > + &domid); > > + if (current_pages <= 0) > > ... why <= ? Gives the impression you may mean to cover HYPERVISOR_memory_op() > returning an error, yet that'll require a signed long variable then. Oh, indeed, current_pages should be signed long. This was an untested mash-up of a slightly different patch, where I didn't realize that current_pages was unsigned. Thanks, Roger.