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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?mdahBzgFG0IX6sG9YoZflL1zkuXgxfv/18IRu1ApU9LI8YleBRIGCB0kQO9G?= =?us-ascii?Q?XZpLoh1TgfhTQFZTtK9K3AFzpq5t4A3BGMcEQBBgyw+Slbii/4662DEfGmyr?= =?us-ascii?Q?TrDAbz3DGIn+ydWXMhn8ZUhDozHKXfpgkAWEVk+4eZ4GButQz1N/vWPF6fHY?= =?us-ascii?Q?JaGQLTerfiXGVA2fu5MJB7vuqyH20IytlC15jyvfI/rlZv+bEqBSxW22lEjx?= =?us-ascii?Q?+EMJ37PyOOdYv5arw0r1QZLgh759ep5regBArVtaOlzbKIDn+Qw2VwiL2JoY?= =?us-ascii?Q?CO9Tl649jkwetjF6t5xKLDpIAzWvfIqrIAxnyOnsEX7Py7z5Yh0p3COL6HFo?= =?us-ascii?Q?Ye6zyaGxQC0dakKUtQh8g+RgYe7vT1rq4UIKXVBLYCLA/cjXScFN2w6UU4Rl?= =?us-ascii?Q?IN2TEoGJUvi/c5WQf2/+eTqHssa1Dcb3d1kHw4y5aD4v4ahy2eVwgO+2eonE?= =?us-ascii?Q?91UWixwHas64UsHffJeJpOUDp1JuYBkg3NHHlI3qwuqtCw6YWouE0d3rLkqZ?= =?us-ascii?Q?7Gp4o5UkKx3p2BTr26Cj8U+EifIDRL1v20bp1HR6ThD8VIbbSbmvZ2vbmUST?= =?us-ascii?Q?C2XT9aCJADhaeBpuRtUtNYNcI7X68Dur+DINWY1BBQU5kgBViTeddXeIf4nT?= =?us-ascii?Q?dStG6EeS2CVAWtfrRnED0U5m8y3h1GyQLPvOCskv4HoSCaLWHcmBp/LvhmrJ?= =?us-ascii?Q?GZBxqL8JtRQAw761RYjf4jIuz5YAXNv9zHtRK2ZuwT8jwCiF8iTGXlWhkHNU?= =?us-ascii?Q?0UtjoeX4gxDOVWxm6A/hTOSWACCUSZ4PcXU3/8V13DsefEpY31FHI54+1Ahc?= =?us-ascii?Q?1XNtEmyqrfpBxV+V51s7wlIcLgUXNqcJsmJqCEpPt3Xu7VP6dJaUpGswzpzm?= =?us-ascii?Q?rfkRlOdFn1vvup23oFqiyIkz3Zyx1CI+Lmyhar230YGjsKqFu+VqY+ambUrx?= =?us-ascii?Q?gKdOWVOp9BysF+yAmHiqbWxIfnswBA0R5jgN0YNHegwi8+l7+2rJBegH+7oV?= =?us-ascii?Q?NqhsAF32FgmqzoktaYVxSQcDzZokX08KzMt3BnzTOkCOJ33AjBYtjHL6OQow?= =?us-ascii?Q?BG+iH0Q45nIsUraCc99F/zgzasfKkyLqAIHNeNFGJ6EAtS6jlBTlW8omxu5c?= =?us-ascii?Q?sQZxZ/UMP1fDHFnZ6Oi2H5oqOKfHUgLPY1NmR8/Xffcn5ErbOKEVp6wbjKkb?= =?us-ascii?Q?lIVD1pzvYGE4smOzgxGzcjWHGXevAk6Sc/BTrC2LZ2OzO7RURPsmsOU4N49o?= =?us-ascii?Q?5e/oDrwvLYK/xm+dvBKt+tHqM6dHi811MvRqT/QVmZ6vSh3MQJaOIFbT0x0x?= =?us-ascii?Q?nWAFDeULWf3bivvbllagh8STtKdDh8Y1zGii/54KQfECR3x+IhTIg+4djV4t?= =?us-ascii?Q?lGERRanx7Ub8dFsJfDdu2PK6EZoTCwOaefq0pU91WrYJIc1Z00TYs448c82E?= =?us-ascii?Q?gxJ1sS5xNLZTkUoMb2KNC+nslOxC+S0Ju+8hfq+6xoNWoRUSCr8vxYz1NsIV?= =?us-ascii?Q?N6OXXh3sn+J1oeHxr40o0BA1c9kwbGyKAkULb8RqbxXql01m9LK4pdI1hYqb?= =?us-ascii?Q?ehSNflYJvXIC5MJ6s18GxegBs0nzr0PJowr7oTFAvEHOAoUgrfoNq99VY60z?= =?us-ascii?Q?UM3AItR5nXDu6WmH462Z9o3V6dAnqLnqqOXXD6VfPPbdNnR23kzWpPn2WQet?= =?us-ascii?Q?sL1xHKmDbDDNyqunM3SVnAcQbwPt5SbXbF1DVTIrfcCF4zJzJK+C52bKubP6?= =?us-ascii?Q?WZwql34W1g=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 49696138-efe4-47ea-5792-08dec222c228 X-MS-Exchange-CrossTenant-AuthSource: SA3PR12MB7901.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Jun 2026 10:19:27.7051 (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: Y8fnXfy/ssonE32mioU8t4v/XW85tv4RM8OHHWj7Z2erpQgtGr0VleW5jUBDJTMK0edmbzhkXxRUsrFQuBKiQg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB7819 On Sun, May 31, 2026 at 11:07:03AM +0800, Yuyang Huang wrote: > /proc/net/igmp walks the multicast list for IPv4 interfaces locklessly > under RCU and prints state->in_dev->mc_count. Concurrently, device > init/destruction and multicast join/leave paths update the count > under the RTNL lock. Fix this intentional lockless snapshot by > annotating the read with READ_ONCE() and the updates with WRITE_ONCE(). > > Fixes: 1d7138de878d ("igmp: RCU conversion of in_dev->mc_list") Pending Paolo's approval, please drop the Fixes tag given the patch is targeted at net-next. > Signed-off-by: Yuyang Huang Code looks fine: Reviewed-by: Ido Schimmel