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Thu, 26 Feb 2026 21:01:56 +0000 Date: Thu, 26 Feb 2026 13:01:44 -0800 From: "Luck, Tony" To: Borislav Petkov CC: "Li, Xiaoyao" , Rong Zhang , "Thomas Gleixner" , Ingo Molnar , Dave Hansen , "x86@kernel.org" , "H. Peter Anvin" , Fenghua Yu , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH -v2] x86/split_lock: Restructure the unwieldy switch-case in sld_state_show() Message-ID: References: <20251215182907.152881-1-i@rong.moe> <20260104191726.GEaVq8xqi0OhsIs284@fat_crate.local> <20260107112835.GBaV5DY1sc3HeLKINb@fat_crate.local> <20260108103850.GAaV-JOgVZNHuZIkBh@fat_crate.local> <20260226145033.GAaaBduQ0rWXydOkAm@fat_crate.local> Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20260226145033.GAaaBduQ0rWXydOkAm@fat_crate.local> X-ClientProxiedBy: SJ0P220CA0002.NAMP220.PROD.OUTLOOK.COM (2603:10b6:a03:41b::10) To SJ1PR11MB6083.namprd11.prod.outlook.com (2603:10b6:a03:48a::9) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SJ1PR11MB6083:EE_|MW4PR11MB6570:EE_ X-MS-Office365-Filtering-Correlation-Id: 27f80219-924f-4cfb-e8aa-08de757a46b6 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|366016|1800799024; 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> + if (sld_state == sld_warn) { > + /* > + * This is handling the case where a CPU goes offline at the > + * moment where split lock detection is disabled in the warn > + * setting, see split_lock_warn(). It doesn't have any effect > + * in the fatal case. > + */ > + if (cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/splitlock", NULL, splitlock_cpu_offline) < 0) > + pr_warn("No splitlock CPU offline handler\n"); } > + > + } else if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) { > + pr_info("#DB: %s on user-space bus_locks\n", action); > } > } -Tony