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Message-ID: Date: Thu, 14 Sep 2023 07:52:33 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Subject: Re: [PATCH v2] x86/amd: do not expose HWCR.TscFreqSel to guests To: Roger Pau Monne Cc: Andrew Cooper , Wei Liu , =?UTF-8?Q?Sol=c3=a8ne_Rapenne?= , xen-devel@lists.xenproject.org References: <20230913145220.11334-1-roger.pau@citrix.com> Content-Language: en-US From: Jan Beulich In-Reply-To: <20230913145220.11334-1-roger.pau@citrix.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: FR4P281CA0128.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:b9::17) To DU2PR04MB8790.eurprd04.prod.outlook.com (2603:10a6:10:2e1::23) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DU2PR04MB8790:EE_|AS1PR04MB9286:EE_ X-MS-Office365-Filtering-Correlation-Id: 6dd6b050-f440-4e09-683e-08dbb4e6cc1f X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 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:DU2PR04MB8790.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230031)(39860400002)(376002)(136003)(346002)(366004)(396003)(451199024)(186009)(1800799009)(38100700002)(86362001)(36756003)(31696002)(31686004)(478600001)(316002)(6666004)(6506007)(6486002)(53546011)(966005)(5660300002)(4326008)(54906003)(66556008)(6512007)(83380400001)(26005)(66946007)(66574015)(8676002)(6916009)(41300700001)(2906002)(66476007)(8936002)(2616005)(45980500001)(43740500002);DIR:OUT;SFP:1101; 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This imo wants (or even needs) extending to address the aspect of then exposing, on newer families, a r/o bit with the wrong value. > Reported-by: Solène Rapenne > Link: https://github.com/QubesOS/qubes-issues/issues/8502 > Fixes: 14b95b3b8546 ('x86/AMD: expose HWCR.TscFreqSel to guests') > Signed-off-by: Roger Pau Monné As mentioned before, with this Fixes: tag I think the description absolutely needs to mention the (changed) view on the Linux log message that had triggered the original change. It certainly helps here that Thomas has already signaled agreement to a Linux side change. Jan