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Thu, 1 Oct 2026 13:05:52 +0000 Date: Thu, 1 Oct 2026 21:05:37 +0800 From: Chao Gao To: "Edgecombe, Rick P" CC: "kvm@vger.kernel.org" , "linux-coco@lists.linux.dev" , "linux-kernel@vger.kernel.org" , "kas@kernel.org" , "x86@kernel.org" , "dave.hansen@linux.intel.com" , "binbin.wu@linux.intel.com" , "bp@alien8.de" , "mingo@redhat.com" , "tony.lindgren@linux.intel.com" , "tglx@kernel.org" , "hpa@zytor.com" , "yilun.xu@linux.intel.com" Subject: Re: [PATCH v3 09/10] x86/virt/tdx: Use early returns in get_tdx_sys_info() Message-ID: References: <20260930053901.22528-1-chao.gao@intel.com> <20260930053901.22528-10-chao.gao@intel.com> Content-Type: text/plain; charset="iso-8859-1" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-ClientProxiedBy: TY4P301CA0093.JPNP301.PROD.OUTLOOK.COM (2603:1096:405:37a::11) To IA0PR11MB8380.namprd11.prod.outlook.com (2603:10b6:208:485::21) 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: IA0PR11MB8380:EE_|CHXPR11MB9674:EE_ X-MS-Office365-Filtering-Correlation-Id: c74f6870-ce1a-42bf-1f73-08df1fbcb8b2 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|23010399003|1800799024|366016|376014|4143699003|11063799006|10067099003|56012099006|22082099003|18002099003; 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It chains its metadata reads >> with: >> >>       ret = ret ?: get_tdx_sys_info_foo(...); >> >> The function is maintained by hand now. Use conventional early returns >> instead. >> >> Print the module version only after its metadata has been read >> successfully. The "ret ?:" chain had no early exit, so the pr_info() >> between the reads ran even when the version read itself failed, printing a >> partially read or all-zero version. That isn't considered a big problem, >> but early returns make it easy to avoid. > >Nit: The reason it is good to change it in this patch is because not doing the >early exit looks very obviously wrong now, where it didn't before. Good point. I was struggling with how to justify this change, and your reasoning is better. I will add it to the changelog.