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Miller" , Jakub Kicinski , Paolo Abeni , Simon Horman , netdev@vger.kernel.org, eric.dumazet@gmail.com, Nikolay Aleksandrov Subject: Re: [PATCH net-next] net: bridge: remove stale rcu_barrier() in br_multicast_dev_del() Message-ID: <20260519110155.GA415776@shredder> References: <20260519095540.2643318-1-edumazet@google.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260519095540.2643318-1-edumazet@google.com> X-ClientProxiedBy: FR4P281CA0419.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:d0::18) To DS0PR12MB7900.namprd12.prod.outlook.com (2603:10b6:8:14e::10) 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: DS0PR12MB7900:EE_|CH2PR12MB4119:EE_ X-MS-Office365-Filtering-Correlation-Id: 58bbd444-a3c4-49df-e10d-08deb5961313 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|1800799024|366016|22082099003|56012099003|18002099003|11063799006; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?+vFzFQtrxiU9cdxk0ux7bAdelbW+6/Jikr7xLo1rkxNtQdfMPjVngH9ZaOvr?= =?us-ascii?Q?VgYy55bxk6j2Z6aAWqV40SXJH7Rpo6djFJj9sajpNTWIqK/qa5TNMgA18bt2?= =?us-ascii?Q?CoqOD7t2OoZAxxQCvV54+uJNSY/vQy/gMQCmIAQKS1pJw16rph4g/5On8g2i?= =?us-ascii?Q?Mv5doFhGaCh3G+/0oW5PAyvnzwTPT1puckh4TcVj4VfeTZ0Z3IoSlPub1s+x?= =?us-ascii?Q?PKbkbiF6oGcnS72uq8iY0wX3FPB99rCCHkpiZLFkB4KogKqfUE+dEtqqSINd?= =?us-ascii?Q?SB0WKIpLMqbJQwr3s0TmCoLaJkOn+azhmGMcFoeuuxqV49b9QGVFVMtaZH6w?= =?us-ascii?Q?ADlsFIEW5emORwIeq4s90EbBDM+FxdPXdwQ01SZ2nEgeyv54DijQpyfVGY2I?= =?us-ascii?Q?8h1GGlVBAMqTzedRio1E7r0i/MiqZoWpFs2PghJVt4vWP7nTn0pvzwRjcpRm?= =?us-ascii?Q?QU5Qj/RcoG0Hi6b/GQ584vQA88gVeqj/cybGJ9tEsV0R+AgnqbIB+2EKF+r4?= =?us-ascii?Q?xE9TiErpOhrx2U1M5WecnJ/HiYoawVSBx4SryrNmnxrlB6mBFVQ0R8uFp5Jf?= =?us-ascii?Q?fDKT4Wmg2et9MhHpcszV+vbTJ7Cw2kDUsW2AHkLl1B8+Iyz/vlIpMNGdzD68?= =?us-ascii?Q?LkjxB/BDpozQR5SUoxFeR4MO5pEnG99nmCjBtAncSE10+fk+Osh6VJ+KaA7H?= =?us-ascii?Q?abB8L2m6KUP2hLDWYvtf6TPk1j/PlhZ9u/WrfA8WbTiQmAWEw6Z2Ob4Rph+N?= =?us-ascii?Q?RLaAFwCst6nXqBhyG3BwLKmZ5L6kiCeaAQvV+eQ+bqcFjVVfCfOFZ5T/yrfT?= =?us-ascii?Q?1x7pR9NwfeYAF7NMR4qjfcvEJPw6P7aAa0DfwrdELrXuSKSwcrDCWuLnjuhh?= =?us-ascii?Q?dZcHWt7AZW90iZ/foA9Plq9xDuaUzThLCs2+e15AjljSYlprc1xeMfda/QnW?= =?us-ascii?Q?XhVzN/v35iWgzGkIYheKtnwg82Doop5+HtIFS3dgDZdmOvwj3SPC2nFSqJMU?= =?us-ascii?Q?aP6e1Rwr7uZXZlVQqz8aZUuee75qtDwszU4WDJcANFnwrteDGF/Ez04K0+xH?= =?us-ascii?Q?D43E/AW3HUcLR/54bTvVeg1U5Nani+VJ9ZLJ8lPvWC+tdm1iPKD5BL2Zy2fk?= =?us-ascii?Q?Og/HQE1qcJSTAoFZMhKHS5/5Pg1hKw/1TLlwGH0KYxeh3o2EDZ7d9AGJ8ON2?= =?us-ascii?Q?aoDsLi5/EFAQRJAhjtNFHfip8/i6V6hkAohuoRquhj1fPH55UtbwShgL1wY+?= =?us-ascii?Q?KQCh1lh5AUQeon1bdqNvAWABwI3mtfVd6hiLiGFMpYhBCbEqXoYDcn3Z87Jx?= =?us-ascii?Q?YWlN37TG1YyqT3ABZb29O8Ww0VVQVkzq/7ae4ADaH5wBZS8TUDOXCvr8WQBp?= =?us-ascii?Q?JsaNxLHpR3brOrs+9TlrtNrxMektMDSZjwsjt6ZuM4ftY4CzehJ6rkuxAjB0?= =?us-ascii?Q?/xmRBdfakadD62BNWC3fA5xyHLIw9v4g2setNMWbWh9rg1jsVcKJrssGEgG1?= =?us-ascii?Q?JBFhXrhVoyRNMGpfjdOr/30kcIvcZ0ZewbnsYQD95j7jbJLzp1IMsKUNUaOq?= =?us-ascii?Q?GbhGS+iX8dQumaz+S2jFmrD1kegx6bCA4sNsO2nrbte4P3aon51gq+7mYs1z?= =?us-ascii?Q?zsw0Ox9eb0ZwuJXBrptX3a9AuLJLix8p5/kX+mihrs+sllHMJxPHywGJxmLP?= =?us-ascii?Q?t1gwBrPydJbROfYUdPIcShOLSLJ2vRpkRx7s3pzkOWtq0183?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 58bbd444-a3c4-49df-e10d-08deb5961313 X-MS-Exchange-CrossTenant-AuthSource: DS0PR12MB7900.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 May 2026 11:02:10.6050 (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: 2Gm3TXIbCsTENTGycLwnDltSUmFeKED0B2p90MonptEI6ftad1LSb5mbJTIjSZtre2urSuNJjjxJ/yjaAjppcg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR12MB4119 On Tue, May 19, 2026 at 09:55:40AM +0000, Eric Dumazet wrote: > This rcu_barrier() came from a time call_rcu() calls were used in > net/bridge/br_multicast.c. > > Now kfree_rcu() is there, we can remove this problematic rcu_barrier() > which causes extreme RTNL pressure in many syzbot reports. [...] > Signed-off-by: Eric Dumazet Reviewed-by: Ido Schimmel