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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?8MCFzd51no/52FyQtOZlq1MAfKB9fkzmgUAb7HWcyIHUJW90SGp1/weaKejx?= =?us-ascii?Q?3KJbclBOQpfltNquvvd/0/VxvKD3qxOxvED6rDA8uxr/swNqRocHGaBcbJaD?= =?us-ascii?Q?4ssZ3TYyxxjdngTOCBza6mLShJaLzDwXOtVml1rDlpdKQzeR5qzPlGsTwyCA?= =?us-ascii?Q?ffZkRkUDeeln5v+8rjA4Ho2WON44ejJ2RQb7GuAN4ASK0oXaDkRGHYraJ89g?= =?us-ascii?Q?jgD/M3vrya9l4rFMKhBqn2A+4vQngOWnLjtU4KUrX/sCA1RufhSiiKV0NaKO?= =?us-ascii?Q?LaSkoLy3GY49ULODg0mmz1fpD0ydm56QZswPqDK2bpaUTHk/k+O7UxMC4cIY?= =?us-ascii?Q?22RLiJCXKU67FrEGe+jqWK9777pYdHDoUpIKiqkq2/D/v4A57WO+iWY7ILQX?= =?us-ascii?Q?RJDkWnLNHvxtFUuJ5Lhgsfc85NLkO5Fe5HNrRkDG/tfPz8L5fsKfI04CCGM9?= =?us-ascii?Q?yaceynpV0o+U4YdWzdcGR997YpWPX7nwszM+uRqhllg/qV+MZb3whnzp3ONv?= =?us-ascii?Q?vyEV7c5riQktA5gyXiOuwgSjJJoHDsfDXa/8Lc1k88QQiJ+0kMV/DdHzxLbg?= =?us-ascii?Q?J9OlVrFJF2siL0Bt3d/O0u96BSZemX3seDyNQw5/2dYCKQNBhJMnt++vqxM3?= =?us-ascii?Q?3KxriurovSn0ERLGLEoEa0pJqyV9GvwEA0M1JBSWEe744+1CdW6V45xwb4B7?= =?us-ascii?Q?agQk4cM65K4PX/PpIfTjRMr3WNE6KdHU/dwIR8ER8zYNo2bQM7NVFJi6SsmC?= =?us-ascii?Q?g+eDMdhSx29Mj3B66V78QSyVrHCS/Yo8N06rb4fN3zNJOhJNGFfiLo0oJJum?= =?us-ascii?Q?5ZibrrPx9KJTxezJ+MCBmOmPNv6HKq0MxLXd/oQnBbivhThwsD8nQvJzV8d5?= =?us-ascii?Q?bEDO5iSvncHer3gfjS4Er576EskYJWnLnk8I69/es1/A/OFC2RSniROuUMvn?= =?us-ascii?Q?FW2ktWPBQpFtWz+RSctyuPVfDyqUqxRmCh9QcxAHhUWHczQ3c3DrHNhmfmeA?= =?us-ascii?Q?cuIFAbocB+R4N0r8edBZi6K7Va9DzUcyzcnaCjvru2Dbw5pmspmUGTWm1wtb?= =?us-ascii?Q?LD/1yiFHitCRli9yTgu9lrbax8F7URjX5/tskxnqc062cBMqLSooNuc7ByL1?= =?us-ascii?Q?u5fn44wcjZExXZmUMnjac6QD1QijsU3RpKagFHwfR19MHiB03p/dNSQF53le?= =?us-ascii?Q?+NM/J6MELqrsIdQjx/OabuU/P2jn1S9lU8TekNWuEZtsK5NhigGfHtyv5zNW?= =?us-ascii?Q?KjfO3Hedz8dBEFpfzNTvC0Z9hUH+rpjwp4W33mVX263mU2S3OoBQjgkaNRee?= =?us-ascii?Q?ydm74tcCPmCsN813mo6o0b3Jf1swUlM417jIl8dq3ZhGQiBU80Z/lUdGd88G?= =?us-ascii?Q?1/WiscdyV8YR2d03bzwTaq1Be4Cdm9fCECB+WNeHTQd7hLQOoYEmEbIE3GsB?= =?us-ascii?Q?YcsQ6yFn2E6Zgfdy19fWsPZnw4o28a1Mg+u64cdkAArGtizhloPLv92rzpRL?= =?us-ascii?Q?vEaCxR87jQk7fLpRMfdVIS1eU6naoS4QFlikNnRhpEibm+x07hSI4LIKIlwQ?= =?us-ascii?Q?CHU/LpULNPwVe55OQEoXuofZTulZbdrdjS3JsbLafABMBiWbfZC2CJfKRsus?= =?us-ascii?Q?fS+MntDs/LLs+dmomgXpyyNclP2BirLc585da0x1zcVN7rImzjuEuaBG9err?= =?us-ascii?Q?FHv6b/jxzGBMlj8ZJnbv8co8nDZSVDvxzf6Ioks8zhl3u7p4?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 147786ed-f9c4-4f40-a159-08df1227a4d3 X-MS-Exchange-CrossTenant-AuthSource: PH0PR12MB7957.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Sep 2026 06:15:59.1059 (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: CnaKCAqGfeoQuL+F4NOF0r2vCJKrwn4+6U5+2xwmd3gmEVhlPp6TM7b9rCuZFIAPB1VhlyuLJlKsvgq+Pfr3dA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB5593 On Fri, Sep 11, 2026 at 01:50:21PM +0300, Nikolay Aleksandrov wrote: > This is a follow-up of one of sashiko's pre-existing bug reports. > br_mst_set_state() calls switchdev_port_attr_set() for nonzero MSTIs > while holding rcu_read_lock() which invokes the blocking switchdev > notifier chain and may sleep. Nonzero MSTI changes come from netlink > with rtnl held. Move the switchdev call before entering the rcu section and > assert that rtnl is held. > > The call cannot be deferred because netlink needs its error and extack. > Also DSA reads the old bridge MST state during the callback and checks it. > A deferred callback will be late and will see the updated state. > > Fixes: 7ae9147f4312 ("net: bridge: mst: Notify switchdev drivers of MST state changes") Nit: blaming 3a7c1661ae13 ("net: bridge: mst: fix vlan use-after-free") would be more accurate, but in practice it doesn't matter since this commit blamed ec7328b59176 that is present in the same release as 7ae9147f4312. > Signed-off-by: Nikolay Aleksandrov Reviewed-by: Ido Schimmel