Could you please take a look at this bug and code review? We are seeing more instances of this bug and found that reconnect_work could hang as well, as can be seen from below stacktrace. Workqueue: nvme-wq nvme_rdma_reconnect_ctrl_work [nvme_rdma] Call Trace: __schedule+0x2ab/0x880 schedule+0x36/0x80 schedule_timeout+0x161/0x300 ? __next_timer_interrupt+0xe0/0xe0 io_schedule_timeout+0x1e/0x50 wait_for_completion_io_timeout+0x130/0x1a0 ? wake_up_q+0x80/0x80 blk_execute_rq+0x6e/0xa0 __nvme_submit_sync_cmd+0x6e/0xe0 nvmf_connect_admin_queue+0x128/0x190 [nvme_fabrics] ? wait_for_completion_interruptible_timeout+0x157/0x1b0 nvme_rdma_start_queue+0x5e/0x90 [nvme_rdma] nvme_rdma_setup_ctrl+0x1b4/0x730 [nvme_rdma] nvme_rdma_reconnect_ctrl_work+0x27/0x70 [nvme_rdma] process_one_work+0x179/0x390 worker_thread+0x4f/0x3e0 kthread+0x105/0x140 ? max_active_store+0x80/0x80 ? kthread_bind+0x20/0x20 This bug is produced by setting MTU of RoCE interface to '568' for test while running I/O traffics.
I think that with the latest changes from Keith we can no longer rely on blk-mq to barrier racing completions. We will probably need to barrier ourselves in nvme-rdma...
