A couple more fixes to enable blktests for the fc transport. 1) Another module unloading hanger which can be triggered with the nvme/048 tests: run blktests nvme/048 at 2023-06-06 13:04:49 nvmet: adding nsid 1 to subsystem blktests-subsystem-1 nvme nvme2: NVME-FC{0}: create association : host wwpn 0x20001100aa000002 rport wwpn 0x20001100aa000001: NQN "blktests-subsystem-1" (NULL device *): {0:0} Association created [478] nvmet: ctrl 1 start keep-alive timer for 1 secs [478] nvmet: check nqn.2014-08.org.nvmexpress:uuid:3d0c3f5d-cb37-4bc4-af29-2168953bfc0a [478] nvmet: nvmet_setup_dhgroup: ctrl 1 selecting dhgroup 0 [478] nvmet: No authentication provided nvmet: creating nvm controller 1 for subsystem blktests-subsystem-1 for NQN nqn.2014-08.org.nvmexpress:uuid:3d0c3f5d-cb37-4bc4-af29-2168953bfc0a. [478] nvmet: adding queue 1 to ctrl 1. [407] nvmet: adding queue 2 to ctrl 1. [6549] nvmet: adding queue 3 to ctrl 1. [1760] nvmet: adding queue 4 to ctrl 1. nvme nvme2: NVME-FC{0}: controller connect complete nvme nvme2: NVME-FC{0}: new ctrl: NQN "blktests-subsystem-1" [478] nvmet: ctrl 1 reschedule traffic based keep-alive timer [407] nvmet: ctrl 1 update keep-alive timer for 1 secs nvme nvme2: NVME-FC{0}: io failed due to lldd error 6 nvme nvme2: NVME-FC{0}: transport association event: transport detected io error nvme nvme2: NVME-FC{0}: resetting controller [478] nvmet: ctrl 1 stop keep-alive (NULL device *): {0:0} Association deleted nvme nvme2: NVME-FC{0}: create association : host wwpn 0x20001100aa000002 rport wwpn 0x20001100aa000001: NQN "blktests-subsystem-1" (NULL device *): {0:0} Association freed (NULL device *): {0:0} Association created (NULL device *): Disconnect LS failed: No Association [407] nvmet: ctrl 1 start keep-alive timer for 1 secs [407] nvmet: check nqn.2014-08.org.nvmexpress:uuid:3d0c3f5d-cb37-4bc4-af29-2168953bfc0a [407] nvmet: nvmet_setup_dhgroup: ctrl 1 selecting dhgroup 0 [407] nvmet: No authentication provided nvmet: creating nvm controller 1 for subsystem blktests-subsystem-1 for NQN nqn.2014-08.org.nvmexpress:uuid:3d0c3f5d-cb37-4bc4-af29-2168953bfc0a. nvme nvme2: reconnect: revising io queue count from 4 to 1 [478] nvmet: adding queue 1 to ctrl 1. nvme nvme2: NVME-FC{0}: controller connect complete [478] nvmet: ctrl 1 reschedule traffic based keep-alive timer [478] nvmet: ctrl 1 update keep-alive timer for 1 secs [478] nvmet: ctrl 1 update keep-alive timer for 1 secs [6549] nvmet: ctrl 1 update keep-alive timer for 1 secs [6549] nvmet: ctrl 1 update keep-alive timer for 1 secs [6549] nvmet: ctrl 1 update keep-alive timer for 1 secs [6549] nvmet: ctrl 1 update keep-alive timer for 1 secs [1760] nvmet: ctrl 1 update keep-alive timer for 1 secs [1760] nvmet: ctrl 1 update keep-alive timer for 1 secs [1760] nvmet: ctrl 1 update keep-alive timer for 1 secs [1760] nvmet: ctrl 1 update keep-alive timer for 1 secs [1760] nvmet: ctrl 1 update keep-alive timer for 1 secs [1760] nvmet: ctrl 1 update keep-alive timer for 1 secs [407] nvmet: ctrl 1 update keep-alive timer for 1 secs nvme nvme2: NVME-FC{0}: io failed due to lldd error 6 nvme nvme2: NVME-FC{0}: transport association event: transport detected io error nvme nvme2: NVME-FC{0}: resetting controller [478] nvmet: ctrl 1 stop keep-alive (NULL device *): {0:0} Association deleted (NULL device *): {0:0} Association freed (NULL device *): Disconnect LS failed: No Association nvme nvme2: NVME-FC{0}: create association : host wwpn 0x20001100aa000002 rport wwpn 0x20001100aa000001: NQN "blktests-subsystem-1" (NULL device *): {0:0} Association created [1760] nvmet: ctrl 1 start keep-alive timer for 1 secs [1760] nvmet: check nqn.2014-08.org.nvmexpress:uuid:3d0c3f5d-cb37-4bc4-af29-2168953bfc0a [1760] nvmet: nvmet_setup_dhgroup: ctrl 1 selecting dhgroup 0 [1760] nvmet: No authentication provided nvmet: creating nvm controller 1 for subsystem blktests-subsystem-1 for NQN nqn.2014-08.org.nvmexpress:uuid:3d0c3f5d-cb37-4bc4-af29-2168953bfc0a. nvme nvme2: reconnect: revising io queue count from 1 to 4 [478] nvmet: adding queue 1 to ctrl 1. [407] nvmet: adding queue 2 to ctrl 1. [6549] nvmet: adding queue 3 to ctrl 1. [1760] nvmet: adding queue 4 to ctrl 1. nvme nvme2: NVME-FC{0}: controller connect complete [1760] nvmet: ctrl 1 reschedule traffic based keep-alive timer [478] nvmet: ctrl 1 update keep-alive timer for 1 secs [478] nvmet: ctrl 1 update keep-alive timer for 1 secs [478] nvmet: ctrl 1 update keep-alive timer for 1 secs [478] nvmet: ctrl 1 update keep-alive timer for 1 secs [1760] nvmet: ctrl 1 update keep-alive timer for 1 secs [6549] nvmet: ctrl 1 update keep-alive timer for 1 secs [1760] nvmet: ctrl 1 update keep-alive timer for 1 secs [6549] nvmet: ctrl 1 update keep-alive timer for 1 secs [1760] nvmet: ctrl 1 update keep-alive timer for 1 secs [1760] nvmet: ctrl 1 update keep-alive timer for 1 secs [6549] nvmet: ctrl 1 update keep-alive timer for 1 secs [1760] nvmet: ctrl 1 update keep-alive timer for 1 secs [6549] nvmet: ctrl 1 update keep-alive timer for 1 secs nvme nvme2: Removing ctrl: NQN "blktests-subsystem-1" [407] nvmet: ctrl 1 stop keep-alive (NULL device *): {0:0} Association deleted (NULL device *): {0:0} Association freed (NULL device *): Disconnect LS failed: No Association nvme_fc: nvme_fc_exit_module: waiting for ctlr deletes BTRFS info (device vda2): qgroup scan completed (inconsistency flag cleared) INFO: task modprobe:11758 blocked for more than 491 seconds. Tainted: G W 6.4.0-rc2+ #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:modprobe state:D stack:0 pid:11758 ppid:11585 flags:0x00004002 Call Trace: <TASK> __schedule+0x17b5/0x4870 ? finish_lock_switch+0x8f/0x120 ? finish_task_switch+0x17f/0x5c0 ? __sched_text_start+0x10/0x10 ? __schedule+0x17bd/0x4870 ? do_raw_spin_trylock+0xc9/0x1f0 schedule+0xe6/0x1e0 schedule_timeout+0x7e/0x1e0 ? __cfi_schedule_timeout+0x10/0x10 ? do_raw_spin_trylock+0xc9/0x1f0 ? __cfi_lock_release+0x10/0x10 ? do_raw_spin_unlock+0x116/0x8a0 wait_for_common+0x377/0x600 ? wait_for_completion+0x30/0x30 cleanup_module+0x222/0x240 [nvme_fc bda1ef6f83d00208ba257c5d0ac34dd6bdb58bf9] __se_sys_delete_module+0x388/0x550 ? __x64_sys_delete_module+0x50/0x50 ? task_work_run+0x236/0x290 ? syscall_enter_from_user_mode+0x2e/0x210 do_syscall_64+0x6e/0xa0 ? syscall_exit_to_user_mode+0x5e/0x220 ? do_syscall_64+0x7d/0xa0 ? syscall_exit_to_user_mode+0x5e/0x220 ? do_syscall_64+0x7d/0xa0 ? syscall_exit_to_user_mode+0x5e/0x220 ? do_syscall_64+0x7d/0xa0 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7fa80811aebb RSP: 002b:00007fff80ea0a88 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0 RAX: ffffffffffffffda RBX: 000055a0b5acf1f0 RCX: 00007fa80811aebb RDX: 0000000000000000 RSI: 0000000000000800 RDI: 000055a0b5acf258 RBP: 0000000000000000 R08: 1999999999999999 R09: 0000000000000000 R10: 00007fa808193ac0 R11: 0000000000000206 R12: 00007fff80ea0ad0 R13: 000055a0b5acf1f0 R14: 0000000000000000 R15: 0000000000000000 </TASK> 2) When executing blktests nvme/030 in a tight loop, I was able to reproduce a different hanger. In this case the ->done() function was never executed on the host fc side. It turns out we didn't enqueue work items correctly and thus would only process one work item. run blktests nvme/030 at 2023-06-13 14:03:52 nvmet: adding nsid 1 to subsystem blktests-subsystem-1 nvme nvme2: NVME-FC{0}: create association : host wwpn 0x20001100aa000002 rport wwpn 0x20001100aa000001: NQN "nqn.2014-08.org.nvmexpress.discovery" (NULL device *): {0:0} Association created [23733] nvmet: ctrl 1 start keep-alive timer for 120 secs nvmet: creating discovery controller 1 for subsystem nqn.2014-08.org.nvmexpress.discovery for NQN nqn.2014-08.org.nvmexpress:uuid:242d4a24-2484-4a80-8234-d0169409c5e8. nvme nvme2: NVME-FC{0}: controller connect complete nvme nvme2: NVME-FC{0}: new ctrl: NQN "nqn.2014-08.org.nvmexpress.discovery" nvme nvme2: Removing ctrl: NQN "nqn.2014-08.org.nvmexpress.discovery" [23771] nvmet: ctrl 1 stop keep-alive nvmet: adding nsid 1 to subsystem blktests-subsystem-2 (NULL device *): {0:0} Association deleted (NULL device *): {0:0} Association freed (NULL device *): Disconnect LS failed: No Association nvme nvme2: NVME-FC{0}: create association : host wwpn 0x20001100aa000002 rport wwpn 0x20001100aa000001: NQN "nqn.2014-08.org.nvmexpress.discovery" (NULL device *): {0:0} Association created [27320] nvmet: ctrl 1 start keep-alive timer for 120 secs nvmet: creating discovery controller 1 for subsystem nqn.2014-08.org.nvmexpress.discovery for NQN nqn.2014-08.org.nvmexpress:uuid:242d4a24-2484-4a80-8234-d0169409c5e8. nvme nvme2: NVME-FC{0}: controller connect complete nvme nvme2: NVME-FC{0}: new ctrl: NQN "nqn.2014-08.org.nvmexpress.discovery" nvme nvme2: Removing ctrl: NQN "nqn.2014-08.org.nvmexpress.discovery" [27320] nvmet: ctrl 1 stop keep-alive nvme nvme2: NVME-FC{0}: create association : host wwpn 0x20001100aa000002 rport wwpn 0x20001100aa000001: NQN "nqn.2014-08.org.nvmexpress.discovery" (NULL device *): {0:1} Association created (NULL device *): {0:0} Association deleted (NULL device *): {0:0} Association freed (NULL device *): Disconnect LS failed: No Association INFO: task kworker/u8:4:102 blocked for more than 491 seconds. Tainted: G W 6.4.0-rc2+ #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:4 state:D stack:0 pid:102 ppid:2 flags:0x00004000 Workqueue: nvme-wq nvme_fc_connect_ctrl_work [nvme_fc] Call Trace: <TASK> __schedule+0x17b5/0x4870 ? try_to_wake_up+0xb5/0xfc0 ? __cfi_lock_release+0x10/0x10 ? __sched_text_start+0x10/0x10 ? _raw_spin_unlock_irqrestore+0x24/0x50 ? lock_release+0x2aa/0xd10 ? wq_worker_sleeping+0x1e/0x200 schedule+0xe6/0x1e0 schedule_timeout+0x7e/0x1e0 ? __cfi_schedule_timeout+0x10/0x10 ? mark_lock+0x94/0x340 ? lockdep_hardirqs_on_prepare+0x2aa/0x5e0 wait_for_common+0x377/0x600 ? queue_work_on+0x57/0xa0 ? wait_for_completion+0x30/0x30 nvme_fc_connect_ctrl_work+0x7dc/0x1a80 [nvme_fc 39e2bf78272df3a610fb1f9884513e99038af746] process_one_work+0x80f/0xfb0 ? rescuer_thread+0x1130/0x1130 ? do_raw_spin_trylock+0xc9/0x1f0 ? lock_acquired+0x310/0x9a0 ? worker_thread+0xd5e/0x1260 worker_thread+0xbde/0x1260 kthread+0x25d/0x2f0 ? __cfi_worker_thread+0x10/0x10 ? __cfi_kthread+0x10/0x10 ret_from_fork+0x29/0x50 </TASK> Daniel Wagner (2): nvme-fc: Do not wait in vain when unloading module nvme-fcloop: queue work items correctly drivers/nvme/host/fc.c | 20 +++++++++++++------- drivers/nvme/target/fcloop.c | 8 ++++---- 2 files changed, 17 insertions(+), 11 deletions(-) -- 2.40.1