In the Linux kernel, following vulnerability has been resolved: net/smc: initialize close_work early to avoid warning We encountered a warning that was canceled before initialization. WARNING: CPU: 7 PID: 111103 at kernel/workqueue.c:3047 __flush_work+0x19e/0x1b0 Workqueue: events smc_lgr_terminate_work [smc] RIP: 0010:__flush_work+0x19e/0x1b0 Call Trace: ? __wake_up_common+0x7a/0x190 work_busy+0x80/0x80 __cancel_work_timer+0xe3/0x160 smc_close_cancel_work+0x1a/0x70 smc_close_active_abort+0x207/0x360 __smc_lgr_terminate.part.38+0xc8/0x180 process_one_work+0x19e/0x340 worker_thread+0x30/0x370 process_one_work+0x340/0x340 kthread+0x117/0x130 __kthread_cancel_work+0x50/0x50 ret_from_fork+0x22/0x30 This is because when smc_close_cancel_work triggered, e.g. RDMA driver rmmod and LGR terminated, conn->close_work is flushed before initialization, resulting in WARN_ON(!work->func). __smc_lgr_terminate | smc_connect_{rdma|ism} ------------------------------------------------------------- smc_conn_create | \- smc_lgr_register_conn for conn lgr->conns_all | \- smc_conn_kill | smc_close_active_abort cancel_work_sync __flush_work | (close_work) smc_close_init INIT_WORK(&close_work) So fix this by initializing establishing the connection.