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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?pkulq/QS9D/khlVUfjwZxdXV4ZetlRCSiBxxuoHw3cc3Yn/UZqn13cOzg8yg?= =?us-ascii?Q?cgrQUZDXXzLRcXi9kyL7Sw5Myfw4WecjollT0Ceks8V3SFv0bK/ymlwC1VBy?= =?us-ascii?Q?XSZfR8LZq+QRrUMSyLkjXKDYrCCSawsBkXKlnyenpwsEDZc7UjTxRuhBiZd4?= =?us-ascii?Q?Jvro7X0apkoELcGliFONUPa7lHDl8iyRIZmR1aOpi7+FAFVWV9oYaAUAQgnN?= =?us-ascii?Q?rsP5/PSAHh4W/OHonlGZJ8LBnAg5e7rle3EeLsb0G5q4rbWHHaBIrvnjmEr3?= =?us-ascii?Q?uYAxG1Ks9muE/Ogdj2isFRGOi0z7tQsvs+U+nMzsXpgBK79kCvpqP5EGwAdd?= =?us-ascii?Q?dmoCkEWKswl+kfJXIR2zrf/gF0nVp43PR9b9HYx7J2zdqtok43BymJvDhkHD?= =?us-ascii?Q?TnK37VK7fKZsBOOH9i6x0So5FK6TLaysiqLriVCkppoH5m27K7YqCcwPpc6R?= =?us-ascii?Q?1hHjYC2+9gjoHNNL/UbMU9z6ljGGKcNmo+sq3ORRautb7SfkhwWf/2cDNzsY?= =?us-ascii?Q?hR6ygN4dFYyMlQ1BcwMrXlFnJhK/nmCCuE1tHVWwpWzK7RgenTX5rh5F1Exb?= =?us-ascii?Q?rWf7T+SV01lx6v2FqFT026MedOTPmuxsSc/Q4SzwAOvaKQQLPfg9FQfpZb+y?= =?us-ascii?Q?BLE/ih9hwVv0znGd81qdUKqPnbG+P24ODRCV+Lii7qkoeG05lKMN60rFJAk9?= =?us-ascii?Q?eSDBuQIExcr3rnqELL0E1bVvNIowBJExHNJutmqVY2gutWRojPubxY9lQMBa?= =?us-ascii?Q?/h5EerrDebjwr4wUk9ZWGbgEiPDQm1Az5kjsS4i2686soxbVKR14kmqAVD0t?= =?us-ascii?Q?ctdrlpvk8vWoghR+9vYgTZXvpI5VuneGlgPFfxLH8aVXO5XEuZLNzM1WdRqK?= =?us-ascii?Q?SarSFu6AhQE3/U+cb5INzxfnEwKVy8tgjGw8nvXpO0WY1g+cMZ+wOX6zIq/B?= =?us-ascii?Q?n+CfUodBrZ6ZzxNIjvRwA1xn37ngrZfOq8xuEYyPQOIUpTmVf6GM21+Y879c?= =?us-ascii?Q?sVX1ks9gMfEMRSCaG3JB9MIPZjWF6hyFlRyrvQlR2ACehLT64mNaIcqbMAHc?= =?us-ascii?Q?kAIpdHpYwEVv+1aBu4RGsgw+mk+brUIBMP9Tqqi94OYhRsH/ANb6q/VNmXv2?= =?us-ascii?Q?7JODvB11e3PCyGwcR3Aiqfivs0LqAK31vRX5g45xR41PJDxgA+eyREY0bDlI?= =?us-ascii?Q?3O0ziaUGAMYfbccKmGZXt9a5zTeDwgPGG9223k9nzbM+rO9d1TuscS3/onBC?= =?us-ascii?Q?3EUQAj6OwPD5orVqJgTuLoqP9xoi/tLtxP8qqQMmI4HF0m/UUNHXrMJPNlSh?= =?us-ascii?Q?ieyysdR3FCvwPfea9XxpcUJ32ejnD+uZ34Xipqt0klVQDTVchAzV2mgmPyId?= =?us-ascii?Q?FJvA6jD2DKqJYxhjmBc/mGwWhhkfZ7kJmtf8U2m9KIx8dzUUiv7glgoAu4oO?= =?us-ascii?Q?ngbTZUYkcMy90Mk/fufqMof5uG6qP+f2pML8J2JRVrTrQQpSVJNYbnmU0s1t?= =?us-ascii?Q?vq8V99A464GEgK6F5oiHgOGmV5eVPVyqaLXGLScIDVgIJvFkmnsUJem+TV8T?= =?us-ascii?Q?I2aXtvT3I5Wz/3OpA0StDJIjjcyVUGNWW4pAf695gUO9V3DCSj8uTeSMph+K?= =?us-ascii?Q?86kYAtdvcawxdZL8iv0qGNgm2OOsrcy8gwZCjRu/9nxMopqnaCpE+9I+dEyE?= =?us-ascii?Q?pB/C1/QbWEnfo/ljJ7y0mwsRbCcosexw7Snr+O9SmveBw8ZC?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9023bde6-0a14-4552-b986-08de9f85e0bb X-MS-Exchange-CrossTenant-AuthSource: SA3PR12MB7901.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Apr 2026 09:10:48.6393 (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: TLWtNyDUcvOahTVFrIl8GHl8NtGyi4UX0nqLFRjaDjQGknOFx7geap4TJ6vjQj/S0u0xZv40kvg4sJ5ZhRH8Ng== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR12MB5839 On Mon, Apr 20, 2026 at 09:26:50PM +0300, Ido Schimmel wrote: > On Mon, Apr 20, 2026 at 02:32:08PM +0300, Ido Schimmel wrote: > > On Sun, Apr 19, 2026 at 10:53:32PM +0800, Ren Wei wrote: > > > From: Haoze Xie > > > > > > Several l3mdev slave-side helpers resolve an upper device and then use > > > l3mdev_ops without first proving that the resolved device is still a > > > valid L3 master. > > > > > > During slave transition, an RCU reader can transiently observe an upper > > > that is not an L3 master. Guard the affected slave-resolved paths by > > > requiring the resolved upper to still be an L3 master before using > > > l3mdev_ops, while keeping existing L3 RX handler providers intact. > > > > > > Fixes: fdeea7be88b1 ("net: vrf: Set slave's private flag before linking") > > > Cc: stable@kernel.org > > > Reported-by: Yifan Wu > > > Reported-by: Juefei Pu > > > Co-developed-by: Yuan Tan > > > Signed-off-by: Yuan Tan > > > Suggested-by: Xin Liu > > > Tested-by: Haoze Xie > > > Signed-off-by: Haoze Xie > > > Signed-off-by: Ao Zhou > > > > I think it's fine for net: > > > > Reviewed-by: Ido Schimmel > > Thought about this again. I would like to check another approach > (synchronize_net() after clearing IFF_L3MDEV_SLAVE). Will update > tomorrow. Sorry about the back and forth, but I thought about it again last night and I think that this is a better fix: https://github.com/idosch/linux/commit/e67517758ebcddf8a1b97817e4ab0fbf82f467fe.patch It's a minimal fix in the control plane of the VRF driver which doesn't add more checks in the data path. I can submit it later this week unless there are objections.