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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 3B696C433E0 for ; Mon, 1 Mar 2021 14:02:01 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id D6E3564DF1 for ; Mon, 1 Mar 2021 14:02:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D6E3564DF1 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=citrix.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.91537.172934 (Exim 4.92) (envelope-from ) id 1lGj7G-0002ZL-1L; Mon, 01 Mar 2021 14:01:42 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 91537.172934; Mon, 01 Mar 2021 14:01:42 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lGj7F-0002ZE-UO; Mon, 01 Mar 2021 14:01:41 +0000 Received: by outflank-mailman (input) for mailman id 91537; Mon, 01 Mar 2021 14:01:40 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lGj7E-0002Z7-F6 for xen-devel@lists.xenproject.org; Mon, 01 Mar 2021 14:01:40 +0000 Received: from esa4.hc3370-68.iphmx.com (unknown [216.71.155.144]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 28cbd892-144d-41c3-94c9-a9c4839e7bb2; Mon, 01 Mar 2021 14:01:38 +0000 (UTC) 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: 28cbd892-144d-41c3-94c9-a9c4839e7bb2 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=citrix.com; s=securemail; t=1614607298; h=date:from:to:cc:subject:message-id:references: in-reply-to:mime-version; bh=O5AEz9nTmvG94Dz/cZ00sMyD8v8tmrNrIFGLwZqaMJE=; b=fw0rDzhBFYFXKNCgQKoVMlnaRo/nlVhiZkdDOFBdjlqOWzuyABtjShpW WfVMbVCBD20b0HtNxpDr6lxjy8DyzZV8Cryt+lxhUy6Lv3vvTPFLsm11G UftABkdDCXiEqs8rd6fQjN+KcJlNuIUAbfWaQCgpz0xZyld2H7HlmUt81 M=; Authentication-Results: esa4.hc3370-68.iphmx.com; dkim=pass (signature verified) header.i=@citrix.onmicrosoft.com IronPort-SDR: rMLn6bj7Mxcp9bZvQjv/xeZlwnfurQ4gHBMWzf0587OqCyUPCvxkOjQB0NJuWcUcfFi9Txq0qz U2EN+NRxn2LdCk0c8YTZ31Z2cEZMrQrXGJtHZvUiOsNtcqyOG1ejVVLKCWhVTeJu+aqqwAUvm0 dbT2Y5qXCb3w6C7HF3tHb8FvdHBioyiJ0VUSKeIcaKBWg3rQleKtfdXkAmWZMu+IAIb9IMNdhc qafBahFFhcw3pjws/cw05Dt8tFG3sRKKvpRsUK7OKYxnEnzP19nbuxsiIPn5yBejgF/oIYD4Nw NCc= X-SBRS: 5.2 X-MesageID: 39636946 X-Ironport-Server: esa4.hc3370-68.iphmx.com X-Remote-IP: 162.221.156.83 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.81,215,1610427600"; d="scan'208";a="39636946" ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=QaQtpyi+hhGoZnXIOJUIgUXbFCcGQeq1fsFY0y75PVyFAoFUHBWeEUYbpdTNXw3h5h+YCLPDHvZs5CMlZG73kpfR4zaHSD0d7fAjlD6MGjwmapCTE+Sh0kPIbwNagGYdXK9wrZ9nsyh9lxZMzSBmtXa3ooTR5DbHPCmqkeylbZTg6jXwYf8RmqFxCKPs1FjtGB85Eh36PJ9B59UhbwdYFX8OfNpCdPHBxNJdTfh8SKojZsSUCIxacYkrxGpIIdZbzUymjux5yOeZALSuFH+BmrAMViHBwtok150MBY6cw0fIoP3tSrMdTpuqcU+jd+GaAmOa/o6OqNpBR/+P7OH4AQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=O5AEz9nTmvG94Dz/cZ00sMyD8v8tmrNrIFGLwZqaMJE=; b=JmsUifwB91IyR5j7bybixCSAjXBCfStIFgIDW3mA28qrF0Q8FmtQGk6xQRyaptJbAvLyBgxGosqr2gBEjun1OG/XB80bRCr2zIk8f7tWVpEHsKXXAKR0I4lFmYIGfl6A5Lf1kCNAiAwgOIqXLkRaU/lVYSKHK7+8YjwXJTpbQmocaqMaLIDPFYyItc4wj5pDsCeU9RYpIv0F0wJChat/4DZZ1HiqmFYRMRMsyVWL8NKRyhwQYE20QQt/9vmQOnNxurTIbLVovwRUSXN7e7iEqeYbjyVqaeIhLCUR3NPxti933GTemg16+a7JgMV7BaTunbgqYx0oA5I0f536guihTQ== 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.onmicrosoft.com; s=selector2-citrix-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=O5AEz9nTmvG94Dz/cZ00sMyD8v8tmrNrIFGLwZqaMJE=; b=Y2Xausy7RaT5Kd08+m2oyq76nLW+EQWczvKXCP6Fc0XV6bkU7qiOojwkp2s+CS59LWsPZvRDn/gfLRuX040WUPTd/QCbeYLmB2snVEShRWUYkdjsvbz6kbxzknEfRtmAKoy9hXAsQBswrpEF1R1Qa9bzXY8SFGwgFjI1GSdU1Ik= Date: Mon, 1 Mar 2021 15:01:27 +0100 From: Roger Pau =?utf-8?B?TW9ubsOp?= To: Jan Beulich CC: "xen-devel@lists.xenproject.org" , Andrew Cooper , Wei Liu , George Dunlap , Ian Jackson Subject: Re: [PATCH 2/2][4.15?] x86: fix build when NR_CPUS == 1 Message-ID: References: <1d8d5089-32a9-9c42-5949-8f9cd20f33e0@suse.com> Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1d8d5089-32a9-9c42-5949-8f9cd20f33e0@suse.com> X-ClientProxiedBy: AM6PR0202CA0058.eurprd02.prod.outlook.com (2603:10a6:20b:3a::35) To DS7PR03MB5608.namprd03.prod.outlook.com (2603:10b6:5:2c9::18) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 3ee85fe5-65e4-43e8-d3db-08d8dcba85eb X-MS-TrafficTypeDiagnostic: DM6PR03MB3740: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:7691; X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; 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:DS7PR03MB5608.namprd03.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(7916004)(39860400002)(136003)(366004)(376002)(396003)(346002)(33716001)(5660300002)(2906002)(8936002)(6486002)(956004)(8676002)(66946007)(66556008)(66476007)(83380400001)(85182001)(4326008)(186003)(6496006)(16526019)(54906003)(316002)(26005)(4744005)(6666004)(478600001)(9686003)(86362001)(6916009);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData: =?utf-8?B?R2FiaFZuTnF0ZEZWZ3FneUwwTUhqd2k5elEzQmlmY2wwQkUxcjlWMXFvSUZM?= =?utf-8?B?c1hRb2xpYThWS050UnNwc3BtWXFtSDhBcGh6SUhlMmh0dmcrbGJYTGN2M1kv?= =?utf-8?B?NU0vNnhKV05seWRZK29VTnNNOUUxZFFlbXBQU081cWltWnIyTWU2b083K1dK?= =?utf-8?B?Myt6Y0NHZ1dacUFkWHpxdWtTeUVySUYvNXBrZE1nTzNzTXJhdEtXTjJCMHJr?= =?utf-8?B?WVFTdmVTUGs5RnhaUnNrd240NzZQNzJsWHgwUUFzemtjV1EraFlHOGcwb1JK?= =?utf-8?B?Q3BJeW1VaFI2WFFwd3haZ1NXeVVHcXlOWDNiSWpMY0ViYjJmMTZVNGF1YlNp?= =?utf-8?B?RDVRMUV0UENoSjNuRXVidmNINHdXVGQ4NFlwT1pOQmc2R0tBUDM4bVN0ZG12?= =?utf-8?B?ZUJsaWNiNE9MN1EyQlNjcTRsN3luVHVHd2tOVENVRjMydWtTVytkckNkbHo4?= =?utf-8?B?MXYxLzZtMjF3S1JOVm5DNWM1Vldpa1l5ek1JNEdRN0FveE84VVMyQXRCMUhN?= =?utf-8?B?U1pzOW5yTU95cFRwajJEY1djcVBPNVVOcHpzWlpldTBqdjRlNUY5eXpoYUdO?= =?utf-8?B?WWViRWJIVkthckV4MThuTU5kK3p4VnpHdm8weTU5V0xieXNoMURObEppaTN0?= =?utf-8?B?Vnh2ZEZPQVFNS3ZlSW5UNTNTZWlHSUpqMFd5Z0xhZVdhdmxtd3RuTzluYlU1?= =?utf-8?B?bFc5eGlldTRPeDFmb0pmT0M0ZUF0aDhWOUlMckduZ1U3cXFTZ3JqL3BxczNo?= =?utf-8?B?VWpmRmhXTFVoUDh0UXRCQ0ZSMlNaU0p3WWVIdm9oTFBZVHBOZWpuVnpOWXM3?= =?utf-8?B?cnBiMDhVeTB3OU8vL0JLRkFZVXo2RzF3amtzeWRiWHQ5Q25BMmtpQitnVXZN?= =?utf-8?B?V0F0RjFUWUpySjcxRVJkWU1yL3pjVUM4S3hsVjRMZmt5K0hyME5jMVhDUWlo?= =?utf-8?B?a29WdmxJdVdhTDRYcmFaZ1NSclpnc3JOb2xxQTFkQ05JNnRjV0dLVmdNbFB2?= =?utf-8?B?RjdOZzNyU0JqNFRxOEp2VXl4UjkwU09tVkJpTm4rRDlheFJIdW1ndFFIcHJX?= =?utf-8?B?dFkvSDRKTHd5emFLZTZSUEpONHhpUGVHa1A2UVk3SXJYMHNGSy84RnFYeS9L?= =?utf-8?B?Ui9VOVVMd2M2N09HWXFBT0YvVnJQcDNERTRDVnljUVdad1lxeGJ1d29nd284?= =?utf-8?B?RVExWTdVbitWZFBEK29CdFgwMnhuYlZCVi8welhLM3hKVzh2Y2lBRUNvTEpo?= =?utf-8?B?dTJDODZ5a0ZUZE50bWdET1dVL0x4OERHMmVSYkhPZHFQWVNQMVppSEFqMEFv?= =?utf-8?B?c29DbGZHNWhUWnd5aWVVNG94VFVuSGNDWGVIbFIzMU85MnlMN3Y3VXZrc1ZR?= =?utf-8?B?cGdydFZ4STJpbUdaV3ZIUm1WZHZCZDBQK3dvZE53VG9RbDVUWTIvb3Y1c0I0?= =?utf-8?B?VDhOREdPL1QrdDNtL08wV0l5S3N4T0U5c3hyTysvUVB3Y21aQk5pSUUwVHFZ?= =?utf-8?B?cnJWV1VtV2RIeHJZbnJ2SE5yUm9VSWt5NVFkN1o0QndhOFhqbWdZMTIxNTNL?= =?utf-8?B?YkkrQVQzcUQwakxnZzRRaUVhYXEzUUlTSmlvWWtQMGREYnJnMG1LRUhvYTRN?= =?utf-8?B?K1VaZ3QvZDRkVThheHdzVXZSSDNwK1ZiNzI4U3Z0c0w2NVFGUDJvT3ErRHd1?= =?utf-8?B?ZjlHWlFIU21xWTdDajVTTnFFNFNLS1hIMmxGRDF6OFpPdmpRSlNpWmZ3QU5s?= =?utf-8?Q?7hcFEHFfZzneVlyxlXUPpzO98jF+VW3fj+OXx1f?= X-MS-Exchange-CrossTenant-Network-Message-Id: 3ee85fe5-65e4-43e8-d3db-08d8dcba85eb X-MS-Exchange-CrossTenant-AuthSource: DS7PR03MB5608.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Mar 2021 14:01:34.3052 (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: RQy8mSHv0qOZ/8qHomC5tmOR+sCsyKE9o3ii/AvyZny7aPAuyErXxvMCECYh0Yx5ZPCUVYILziGepiq4s1eFHg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR03MB3740 X-OriginatorOrg: citrix.com On Mon, Mar 01, 2021 at 09:31:07AM +0100, Jan Beulich wrote: > In this case the compiler is recognizing that no valid array indexes > remain (in x2apic_cluster()'s access to per_cpu(cpu_2_logical_apicid, > ...)), but oddly enough isn't really consistent about the checking it > does (see the code comment). I assume this is because of the underlying per_cpu access to __per_cpu_offset using cpu as the index, in which case wouldn't it be better to place the BUG_ON there? Also I wonder why the accesses the same function does to the per_cpu area before the modified chunk using this_cpu as index don't also trigger such warnings. Thanks, Roger.