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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, Simon Horman , Jonathan Corbet , David Ahern , Przemek Kitszel , mlxsw@nvidia.com Subject: Re: [PATCH net] Documentation: networking: Add a caveat to nexthop_compat_mode sysctl Message-ID: References: Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: FR5P281CA0017.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:f1::9) To SA3PR12MB7901.namprd12.prod.outlook.com (2603:10b6:806:306::12) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SA3PR12MB7901:EE_|SN7PR12MB8101:EE_ X-MS-Office365-Filtering-Correlation-Id: d9034aaa-0b88-43cd-a95d-08dd186700dd X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|376014; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?8fzMul9gXwkhKE7F/TnSfuGZGafYaPxu5/VrzZpPZDssEQMjlKXeKEx5IMfD?= =?us-ascii?Q?S/pqa++h0gaWgo7aFcH4DAEXbI4CJY/Y9GJ2/cdTZNpI1pT8YiIA4U/h6qx0?= =?us-ascii?Q?NKgmYZJhHwfBRtGZCui67Ken2NmzOPttn53EvLp/yd+8aRaaTVtkahmwqztj?= =?us-ascii?Q?RID7geAnk9z5ZYs62oSniqzxMj/c3WY+3KG7yuwJX42YLupb13WuxV4AZjHu?= =?us-ascii?Q?DAWecvE0hev8SxtC5sLjfKee42bsIoFi2VitYAQ8gzpCAAsDqLOg7xpnVGdn?= =?us-ascii?Q?TqNPSvrqJ61GOSmopsqHkzD7sIXF/y1ltHqrPxDa1oTTvx/nTtVRncWqqazy?= =?us-ascii?Q?mGk8w2SubOMMBQU2BRsYezuZntYrJFfmYnrsK3TSCL2DelB+1cxTFf/VWNwE?= =?us-ascii?Q?x/Bk4tkaHWFVADhMlu1t79RT0y5kWwZUY3s9vHoqGxqDMamEpwc6MLWFG5Fz?= =?us-ascii?Q?bQPE1NZmsVgJVA0W/c0K4xryFx/N70vBkKIZx0IAtCL9VvKO1XJ8DyWhdL+2?= =?us-ascii?Q?5R603v8zOktT8OGSKNmPT4CO1OxlQXvMlSikv0VhvaPssLJBMB4EZU3+dZMQ?= =?us-ascii?Q?XNvMcUN8VHKEmMXu2Sx9yDhLryZ9LOEORGr2aVeGaXaXOHrnWL03gCMZaS7y?= =?us-ascii?Q?IyjwFX9XIFbcM1/BSDccJYWmZtTTjdTY76n6TpNmVFiJgwQRzjQtNNby/Zgr?= =?us-ascii?Q?JPNa+19brki8W0gG16GMTuMJw02gnAM3UoD0f2uPAb0ZtU0u+Xcjr8xNSU7S?= =?us-ascii?Q?RFALBWF4NRRE1HW/pIngs1/maHvMN7G8SLyqII/wKH2COKX7fONs90zRz0ER?= =?us-ascii?Q?e/5cg2e6K1eKv+9wVJcE5rxS4/UlXvCkHLTqsedfBTvMVPv4himAhyh0WUzi?= =?us-ascii?Q?f89mBshjMbucWRsoIEuGTcwcsbfglD7apgnKi8Rqzxn9IiVx0S0bnN098NCN?= =?us-ascii?Q?DzmqwWlO706rm6Fwa5vxmWOmC3JOmgDhCLlKR2Q4QpGpiWwxTQiaq7BroSWN?= =?us-ascii?Q?6qxKvJtSGlQ7qVINdu4X1rXrFPv4y8IsDEwL+LWw8WSSNEK5Kjpz/1qhxPvs?= =?us-ascii?Q?eduTi+KhGB2jctmIMxIJ072bO1mXGw//hYIT579gLREWSAT7cS+qMJXohKfb?= =?us-ascii?Q?nz4pUEi9OKGF9jsqrzVkKYfXachqBl9thgPdz56pnnJhLUhzkruFaPMLsJc/?= =?us-ascii?Q?vfc8cOtUbMFynOKTO9uKJA8yOZPom93yowSCsZ0wIFqOU++pIj0hh9Js40Jw?= =?us-ascii?Q?xvimCUD0vVJZHeR7/1Tgw7n7GqOXD53E94PtFLiYYy8plgCcNRZI/ZOAlgPp?= =?us-ascii?Q?6BqOIiuTyXrE9uUPgg87CKZYVTWeD+q5zpv3MjJBBjkvkA=3D=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:SA3PR12MB7901.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(1800799024)(376014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?r1vuPAzcwdMqQYNmK37HFJDfuAqdnT1kD9lsQ7evRQzatWgKM8mmJqdUmNwv?= =?us-ascii?Q?wMTvSJbXnaS9W6H+qTEKHJytJBbPztGAsW22dDj4DpYnkmWnewSBZd1Li0Qu?= =?us-ascii?Q?ubzMEjkg37F7oC4Bd12no3uHpWsc/9Bw2GP7T/Ef1n/tIDB6VT6VtxzGXeyo?= =?us-ascii?Q?H5E69zvo+sYghih1dHxAitk0nSpZt1FHpwyEhuKBwA++0JId4ZsxYkaCesS5?= =?us-ascii?Q?PR31GU47riMOiTxm/YIvyOq+ZGjFQyD1TNPm6xNkmze79wHnAl0xvB2mWClr?= =?us-ascii?Q?yGiJYuUWUDgDgLJ5kMpFwQrOR8bpZZ02TQLvd4xMJ8wtgJ7B6ocZzacNR9db?= =?us-ascii?Q?zY4IvzTO7NoImpw4OIt7UyXQL2hHopKMFCUXmMB9lkG2M17i5uH5FR5pU4df?= =?us-ascii?Q?018DivnfdRiKevvhYXaQejy/L7+6zHyKh9ci6aF6FywazWhj9zRmUtL0iutk?= =?us-ascii?Q?zsVzK0S9z/pf7d/RHuiPzuL/kP28VG+iD8w5W9J5fZixv7vg7cVVNydKddaz?= =?us-ascii?Q?LjkRheUV/EH9ZjX4mlWY+XZesF7QJeiYmo7CUjG+xk+d0oWOqU8MqVjCeyBG?= =?us-ascii?Q?djbSi2apOgAowfdsL0WMosnnLLHyTF4B2NdXCrvESHgl1ptNtG/BYX2hUWkG?= =?us-ascii?Q?ndaiMNc4CYe0Ry3RzT8Qv4uvvb3rj+ucFF3MCOiAJ7MOrXv54ZOzsIruTm6A?= =?us-ascii?Q?qXLGgo87GinBYMTcIF2iKQOUxTiJbSm0Q/dlzOgqGWtSErstHv9EDaqzka+8?= =?us-ascii?Q?u/ib8GMNT9z71sTgOVn8vpIZ6V2pBJOBKCy3nk8hNhK1l1JG0R5/U7bhIRit?= =?us-ascii?Q?v13N7CSCW+0Loamu3X/mNxfqMvbA7OFkZbh2WFCV0p827ekAhnsIkQ4yacG8?= =?us-ascii?Q?lMV2aj5dpvOriUJd4dO4tW6gNw/jeoLzn8lW5Qugqur71bTPXLxdhrzwu2b3?= =?us-ascii?Q?dVDI0hIsHlVRKqe9/gsVKA9ATMgvWkjpXHzApUOtzKBx+0JlG3t08C1QMNGc?= =?us-ascii?Q?KjaDwkhOa+RCrFIxb9QCkBfEOoQsJbHsqMvuGy5oQlUhpadfquRpJsAvzB7B?= =?us-ascii?Q?/m3+Uj2lWf2x/MFs3cDvCaEsRe55yuoBOFszD9Dcuhu72WtUXYKPlQvAI36h?= =?us-ascii?Q?jbY5zuJYdR1M7Gvj1Yt3G5kIi0fLB2bFdwOFDdv7ONGvNV2+LO+YkYCJooK1?= =?us-ascii?Q?Z47P9yYD64LScDuXeAit5ymBuIbSxFoUb0IbUsbzlqnRmbZd6LeyQlyDi8aJ?= =?us-ascii?Q?9sZHqm/770Xd+I9B0mG1apf/4gD9RHtY4zDz1kgajeKzsudJv66aj6Z3XqNp?= =?us-ascii?Q?CCZQ83pcMokh1KbECPqV0x/CATGSgxl8amYsat3YSsFMPtqsO6FcmirUAYCi?= =?us-ascii?Q?CF17X1whxWkx9HAqOs6QA8w/vS3/hZ04NQjShr2GZq2xrDrKNtL5SXXwcMZd?= =?us-ascii?Q?avnD8ZVaZr44Wx+HIWSeYJTDQrb0lnAY511KJErpBVETtcKF6savqX7FT2vL?= =?us-ascii?Q?YTvEihF8RFyVkhkbSmWVLufXrWPK0c7L0ZC88GtxBD/uXF/5Fgh3gv/3twJN?= =?us-ascii?Q?/NsrNRmznaRMZJF21bu85CBEP2BpUicjtSQGsq2c?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d9034aaa-0b88-43cd-a95d-08dd186700dd X-MS-Exchange-CrossTenant-AuthSource: SA3PR12MB7901.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Dec 2024 15:34:43.3160 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 5+DBJCdGzwTTx9BjfPOee8VInSqW1Of7z5CrseF/frnNQHngd3/dkotqaf1k3KGNEfeAsDsgcemkWt3PdLQdaA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR12MB8101 On Mon, Dec 09, 2024 at 12:05:31PM +0100, Petr Machata wrote: > net.ipv4.nexthop_compat_mode was added when nexthop objects were added to > provide the view of nexthop objects through the usual lens of the route > UAPI. As nexthop objects evolved, the information provided through this > lens became incomplete. For example, details of resilient nexthop groups > are obviously omitted. > > Now that 16-bit nexthop group weights are a thing, the 8-bit UAPI cannot > convey the >8-bit weight accurately. Instead of inventing workarounds for > an obsolete interface, just document the expectations of inaccuracy. > > Fixes: b72a6a7ab957 ("net: nexthop: Increase weight to u16") > Signed-off-by: Petr Machata Reviewed-by: Ido Schimmel