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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?YYVyJS6uxhP+GmHs3mhVm1cGMkcNLzbqxyW9THklFzNte5CPyKLtdIGKWesW?= =?us-ascii?Q?J+RaE7/pvqkrNwYPbkCjeQjFucf1y3Qy8hvPs2pVSzO7WLJdeyM6Yw+TFDOJ?= =?us-ascii?Q?o0/Q7iEcg2EGbpPqYohcOqcaX55re9FqZzZx46knSC+mFxvq8G3ZuMce/UhS?= =?us-ascii?Q?7KUdAsVTXIt3oeUC2PlUS6Fil0RtsTg5RQ6xiKy62HjrhTWr/04+ft86kVF6?= =?us-ascii?Q?KYJSipPXe4e8DF6rFKUPVYMLozxPHg4KF8z0DTqYlk7UCBPmQk4uiZOhbeYZ?= =?us-ascii?Q?aj2v6UIT3rnX1p/McpCixvjoeJNSsIG5rkGd2ejb3Dv6GjLQJURseo4+PJMA?= =?us-ascii?Q?xuefLgjRThcpq68qJ5sXxZ5u7jaBFJ2LZTDA9UZUV/rDvpViqrmRZFyq1nBT?= =?us-ascii?Q?DgXFP1GsfD67afUVwDrESWwLYnyDB6dHb+IHciMiLbWEP37Roe1hhDQe94Jp?= =?us-ascii?Q?GaWJlZf6WI5XudfihzdnjCgTh7TWk2NhDCJrcQBRWZyiXVbfoqfhJElCLGZK?= =?us-ascii?Q?r+eAuqIrPF7x8I0kTLpIlQsYOPy5DJ21jqUAR2WBj4XEn+mncwMaoNZssLxA?= =?us-ascii?Q?o3kIizUc4me9a9k/Mw1D5GL/JPmI+BpEZjgwf6E0lQ7TjO6nJaK24otGkjQF?= =?us-ascii?Q?b+ZpFJOaWsD1Z6WRWHSZI6zG2652ICRNlGQVCXkZMPpzXevlf4g2fp9bPD7I?= =?us-ascii?Q?f2GbnTH+tkrVaEbwNoWFuAEk28lg4seYBr9vgimMMn60kiEUYFS3LaN01MaS?= =?us-ascii?Q?bfP/Hv4nYdvdOkqWEJcLhrlEUYUGmUGbZdLcx1zMQEPkeUGYLIbG9MEuxwue?= =?us-ascii?Q?dtgQ9Hu2xfi3JGo9CEOdoz8AUXtqKHpmRJofWDtoIqo2xoHA6dA7I4aUWj0L?= =?us-ascii?Q?J2/F8tFsudhNSI8/aB5Pp3nd6qwWOa5FYTcaZJasFvbJeftsS5xDnYHvwBPo?= =?us-ascii?Q?12Qw9QJCdV2w6Th0IjHHC5mVTKCMRe/EXnaWrK4DUQk4hOAGaNLskCUFN1dY?= =?us-ascii?Q?bkkSGXdO806d9C1lX2NxVOGaPOJLlsGh1JV4Jv9FVVxdNCoRqlZxrI+92tDp?= =?us-ascii?Q?AN/6sdqqCQgvjtTBlTarlVSAK7cTX3IeISN1ZLb7zRpQV2w2vKUcfLcMVXr1?= =?us-ascii?Q?48Y7soXd+mReOpEV2XAdU46fpwIcQlEewRBLY6PUJ2eKvssTXjtCRh9QTlGe?= =?us-ascii?Q?pD0r6GX5auHhiAI/lPyYxT6LuJtlX3aLrPWu4eBu/kvGEu7QXOWBtoeqFdnD?= =?us-ascii?Q?KxEkTTptfBbhd1YWBDLIhYuDFwfhUZU323CnGiONj7P0tes+9lfes3iF3aQE?= =?us-ascii?Q?TuLTXg7ZTbINYbUIWtEoUoNDsE6DJRXEPEazGUxku2uHHpBIswZckCovD6YB?= =?us-ascii?Q?PDrizQXkdQl1ul+qt1xNuVrOHWquA55nf+7sh0Z7Mu58+usgsjBTyslpQ/Tg?= =?us-ascii?Q?/72WX1xoHwwTKGCerYRdYGVJ6Am/8XRK/ScN2dRR9eJEhFa702LP5gbdbilv?= =?us-ascii?Q?j7wBNy5/BX62U+ltgDgiqPEPZHx+i2iNXkI32gdm8FC9EmSgNA9Gi7diIt9y?= =?us-ascii?Q?7H79uKZASVpprlgBQoLcsZRMdAUySWLd+Zgru0+dZAuIXl9KvL2E3/7hboht?= =?us-ascii?Q?X/MSpjr17rcuhUEWgOVg0ygsYvS86SaaabqLOKhHaMSiy5+/ITMh3RELw09K?= =?us-ascii?Q?XsngBPcpYnPLVPKI3TSTsxItJnqsqi658HmzlPmn0/3/DuQLz0vktnhDaiFW?= =?us-ascii?Q?Xevrv2lztQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a7a5a87f-4fd5-41a2-db90-08dec222dc42 X-MS-Exchange-CrossTenant-AuthSource: SA3PR12MB7901.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Jun 2026 10:20:11.7144 (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: qRLC1OJUW+ytKj3owH2Cs0xstG2i5ldJgBoCK1r8tBnxER5tLv1K7uYQUVurZmP4DwNDc/UHf80IxwLk7JguhA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB7819 On Sun, May 31, 2026 at 11:07:04AM +0800, Yuyang Huang wrote: > /proc/net/igmp walks the multicast list locklessly under RCU and reads > timer-related fields (im->tm_running, im->reporter, im->timer.expires) > to print the timer state of multicast memberships. Concurrently, these > fields are modified under im->lock spinlock in timer management paths > (igmp_stop_timer(), igmp_start_timer(), and igmp_timer_expire()). Fix this > intentional lockless snapshot by annotating the lockless reads 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 Reviewed-by: Ido Schimmel [...] > @@ -2964,6 +2964,7 @@ static int igmp_mc_seq_show(struct seq_file *seq, void *v) > struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq); > char *querier; > long delta; > + int tm_running; Nit: Please move this above 'delta' for reverse xmas tree ordering > > #ifdef CONFIG_IP_MULTICAST > querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :