[23462] 0 23462 18113 8711 26 3 0 0 syz-executor.3 [23470] 0 23470 18146 13234 33 3 0 0 syz-executor.1 [23517] 0 23517 18179 8746 26 4 0 0 syz-executor.3 [23527] 0 23527 18146 13234 33 3 0 0 syz-executor.1 BUG: workqueue lockup - pool cpus=0-1 flags=0x5 nice=0 stuck for 231s! Showing busy workqueues and worker pools: workqueue events_unbound: flags=0x2 pwq 4: cpus=0-1 flags=0x5 nice=0 active=19/512 in-flight: 6065:call_usermodehelper_exec_work, 9303:call_usermodehelper_exec_work, 20933:call_usermodehelper_exec_work, 10609:call_usermodehelper_exec_work [23542] 0 23542 18179 8746 26 4 0 0 syz-executor.3 pending: call_usermodehelper_exec_work, call_usermodehelper_exec_work, call_usermodehelper_exec_work, call_usermodehelper_exec_work, call_usermodehelper_exec_work, call_usermodehelper_exec_work, call_usermodehelper_exec_work [23601] 0 23601 18146 13234 33 3 0 0 syz-executor.1 [23664] 0 23664 18146 13234 33 3 0 0 syz-executor.1 , call_usermodehelper_exec_work, call_usermodehelper_exec_work, call_usermodehelper_exec_work, call_usermodehelper_exec_work [23742] 0 23742 18146 13234 33 3 0 0 syz-executor.1 , call_usermodehelper_exec_work [23787] 0 23787 18146 13234 33 3 0 0 syz-executor.1 , call_usermodehelper_exec_work, call_usermodehelper_exec_work, call_usermodehelper_exec_work [23852] 0 23852 18146 8719 25 3 0 0 syz-executor.2 ====================================================== WARNING: possible circular locking dependency detected 4.14.98+ #7 Not tainted ------------------------------------------------------ writeback/25 is trying to acquire lock: (console_owner){-.-.}, at: [] log_next kernel/printk/printk.c:492 [inline] (console_owner){-.-.}, at: [] console_unlock+0x28e/0xc60 kernel/printk/printk.c:2378 but task is already holding lock: (&pool->lock/1){..-.}, at: [] show_workqueue_state kernel/workqueue.c:4495 [inline] (&pool->lock/1){..-.}, at: [] show_workqueue_state.cold+0x22f/0xe95 kernel/workqueue.c:4468 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&pool->lock/1){..-.}: -> #2 (&(&port->lock)->rlock){-.-.}: -> #1 (&port_lock_key){-.-.}: -> #0 (console_owner){-.-.}: other info that might help us debug this: Chain exists of: console_owner --> &(&port->lock)->rlock --> &pool->lock/1 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pool->lock/1); lock(&(&port->lock)->rlock); lock(&pool->lock/1); lock(console_owner); *** DEADLOCK *** 6 locks held by writeback/25: #0: ("writeback"){+.+.}, at: [] process_one_work+0x6e5/0x14e0 kernel/workqueue.c:2085 #1: ((&(&wb->dwork)->work)){+.+.}, at: [] process_one_work+0x71b/0x14e0 kernel/workqueue.c:2089 #2: (kernel/workqueue.c:5419){+.-.}, at: [] lockdep_copy_map include/linux/lockdep.h:174 [inline] #2: (kernel/workqueue.c:5419){+.-.}, at: [] call_timer_fn+0xc6/0x680 kernel/time/timer.c:1269 #3: (rcu_read_lock_sched){....}, at: [] show_workqueue_state+0x0/0x100 kernel/workqueue.c:4367 #4: (&pool->lock/1){..-.}, at: [] show_workqueue_state kernel/workqueue.c:4495 [inline] #4: (&pool->lock/1){..-.}, at: [] show_workqueue_state.cold+0x22f/0xe95 kernel/workqueue.c:4468 #5: (console_lock){+.+.}, at: [] console_trylock_spinning kernel/printk/printk.c:1644 [inline] #5: (console_lock){+.+.}, at: [] vprintk_emit+0x11a/0x330 kernel/printk/printk.c:1916 stack backtrace: CPU: 0 PID: 25 Comm: writeback Not tainted 4.14.98+ #7 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x10e lib/dump_stack.c:53 print_circular_bug.isra.0.cold+0x2dc/0x425 kernel/locking/lockdep.c:1258 workqueue writeback: flags=0x4e [23854] 0 23854 18146 13234 33 3 0 0 syz-executor.1 pwq 4: [23872] 0 23872 18212 8723 25 3 0 0 syz-executor.2 cpus=0-1 [23911] 0 23911 18146 13234 33 3 0 0 syz-executor.1 flags=0x5 nice=0 [23970] 0 23970 18146 13234 33 3 0 0 syz-executor.1 active=2/256 in-flight: 25(RESCUER):wb_workfn [24034] 0 24034 18146 13234 33 3 0 0 syz-executor.1 pending: wb_workfn pool 4: [24117] 0 24117 18146 10285 30 4 0 0 syz-executor.2 cpus=0-1 [24121] 0 24121 18146 13234 33 3 0 0 syz-executor.1 flags=0x5 nice=0 [24168] 0 24168 18146 13234 33 3 0 0 syz-executor.1 hung=231s workers=5 manager: 2313 [24234] 0 24234 18146 13234 33 3 0 0 syz-executor.1 [24293] 0 24293 18146 13234 33 3 0 0 syz-executor.1 [24333] 0 24333 18146 13234 32 3 0 0 syz-executor.3 [24372] 0 24372 18146 13234 33 3 0 0 syz-executor.1 [24395] 0 24395 18241 13296 32 3 0 0 syz-executor.3 [24403] 0 24403 18113 8712 25 3 0 1000 syz-executor.5 [24442] 0 24442 18146 13234 33 3 0 0 syz-executor.1 [24487] 0 24487 18146 13234 32 3 0 0 syz-executor.3 [24505] 0 24505 18146 13234 33 3 0 0 syz-executor.1 [24603] 0 24603 18113 8711 25 3 0 1000 syz-executor.5 [24605] 0 24605 18146 8714 26 3 0 1000 syz-executor.5 [24615] 0 24615 18146 13234 33 3 0 0 syz-executor.1 [24708] 0 24708 18146 8745 26 4 0 1000 syz-executor.5 [24725] 0 24725 18146 13234 33 3 0 0 syz-executor.1 [24792] 0 24792 18146 13234 33 3 0 0 syz-executor.1 [24854] 0 24854 18146 13234 33 3 0 0 syz-executor.1 [24917] 0 24917 18146 13234 33 3 0 0 syz-executor.1 [24988] 0 24988 18146 13234 33 3 0 0 syz-executor.1 [25065] 0 25065 18146 13234 33 3 0 0 syz-executor.1 [25166] 0 25166 18146 13234 33 3 0 0 syz-executor.1 [25229] 0 25229 18146 13234 33 3 0 0 syz-executor.1 [25313] 0 25313 18146 13234 33 3 0 0 syz-executor.1 [25364] 0 25364 18146 13234 33 3 0 0 syz-executor.1 [25431] 0 25431 18146 13234 33 3 0 0 syz-executor.1 [25493] 0 25493 18146 13234 33 3 0 0 syz-executor.1 [25516] 0 25516 18113 8714 26 3 0 0 syz-executor.1 [25591] 0 25591 18113 8714 26 3 0 0 syz-executor.1 [25695] 0 25695 18113 8714 26 3 0 0 syz-executor.1 [25768] 0 25768 18146 13234 33 3 0 0 syz-executor.1 [25859] 0 25859 18146 13234 33 3 0 0 syz-executor.1 [25910] 0 25910 18146 13234 33 3 0 0 syz-executor.1 [25990] 0 25990 18146 13234 33 3 0 0 syz-executor.1 [26071] 0 26071 18146 13234 33 3 0 0 syz-executor.1 [26121] 0 26121 18146 13234 33 3 0 0 syz-executor.1 [26196] 0 26196 18146 13234 33 3 0 0 syz-executor.1 [26252] 0 26252 18146 13234 33 3 0 0 syz-executor.1 [26322] 0 26322 18146 13234 33 3 0 0 syz-executor.1 [26355] 0 26355 18146 13234 33 3 0 0 syz-executor.1 [26414] 0 26414 18146 13234 33 3 0 0 syz-executor.1 [26456] 0 26456 18146 13234 33 3 0 0 syz-executor.1 [26538] 0 26538 18146 13234 33 3 0 0 syz-executor.1 [26606] 0 26606 18146 13234 33 3 0 0 syz-executor.1 [26698] 0 26698 18146 13234 33 3 0 0 syz-executor.1 [26764] 0 26764 18146 13234 33 3 0 0 syz-executor.1 [26851] 0 26851 18146 13234 33 3 0 0 syz-executor.1 [26920] 0 26920 18146 13234 33 3 0 0 syz-executor.1 [26981] 0 26981 18146 13234 33 3 0 0 syz-executor.1 [27053] 0 27053 18146 13234 33 3 0 0 syz-executor.1 [27128] 0 27128 18146 13234 33 3 0 0 syz-executor.1 [27198] 0 27198 18146 13234 33 3 0 0 syz-executor.1 [27272] 0 27272 18146 13234 33 3 0 0 syz-executor.1 [27357] 0 27357 18146 13234 33 3 0 0 syz-executor.1 [27431] 0 27431 18146 13234 33 3 0 0 syz-executor.1 [27454] 0 27454 18113 8712 26 3 0 1000 syz-executor.5 [27456] 0 27456 18146 8714 26 3 0 1000 syz-executor.5 [27533] 0 27533 18146 13234 33 3 0 0 syz-executor.1 [27601] 0 27601 18146 13234 33 3 0 0 syz-executor.1 [27650] 0 27650 18146 13234 33 3 0 0 syz-executor.1 [27754] 0 27754 18146 13234 33 3 0 0 syz-executor.1 [27803] 0 27803 18146 13234 33 3 0 0 syz-executor.1 [27872] 0 27872 18146 13234 33 3 0 0 syz-executor.1 [27961] 0 27961 18146 13234 33 3 0 0 syz-executor.1 [28040] 0 28040 18146 13234 33 3 0 0 syz-executor.1 [28087] 0 28087 18146 13234 33 3 0 0 syz-executor.1 [28156] 0 28156 18146 13234 33 3 0 0 syz-executor.1 [28209] 0 28209 18146 13234 33 3 0 0 syz-executor.1 [28284] 0 28284 18146 13234 33 3 0 0 syz-executor.1 [28349] 0 28349 18146 13234 33 3 0 0 syz-executor.1 [28388] 0 28388 18146 13234 33 3 0 0 syz-executor.1 [28472] 0 28472 18146 13234 33 3 0 0 syz-executor.1 [28565] 0 28565 18146 13234 33 3 0 0 syz-executor.1 [28615] 0 28615 18146 13234 33 3 0 0 syz-executor.1 [28724] 0 28724 18146 13234 33 3 0 0 syz-executor.1 [28790] 0 28790 18146 13234 33 3 0 0 syz-executor.1 [28826] 0 28826 18146 13234 33 3 0 0 syz-executor.1 [28893] 0 28893 18146 13234 33 3 0 0 syz-executor.1 [28936] 0 28936 18146 13234 33 3 0 0 syz-executor.1 [28985] 0 28985 18146 13234 33 3 0 0 syz-executor.1 [29093] 0 29093 18146 13234 33 3 0 0 syz-executor.1 [29135] 0 29135 18146 8716 27 3 0 0 syz-executor.1 [29194] 0 29194 18146 13234 33 3 0 0 syz-executor.1 [29284] 0 29284 18146 13234 33 3 0 0 syz-executor.1 [29329] 0 29329 18146 13234 33 3 0 0 syz-executor.1 [29421] 0 29421 18146 13234 33 3 0 0 syz-executor.1 [29471] 0 29471 18245 8757 26 4 0 0 syz-executor.2 [29499] 0 29499 18146 13234 33 3 0 0 syz-executor.1 [29548] 0 29548 18146 13234 33 3 0 0 syz-executor.1 [29599] 0 29599 18146 13234 33 3 0 0 syz-executor.1 [29646] 0 29646 18146 13234 33 3 0 0 syz-executor.1 [29736] 0 29736 18146 13234 33 3 0 0 syz-executor.1 [29754] 0 29754 18179 8750 25 4 0 0 syz-executor.2 [29764] 0 29764 18146 13234 33 3 0 0 syz-executor.1 [29849] 0 29849 18146 13234 33 3 0 0 syz-executor.1 [29902] 0 29902 18146 13234 33 3 0 0 syz-executor.1 [29980] 0 29980 18146 13234 33 3 0 0 syz-executor.1 [30034] 0 30034 18146 13234 33 3 0 0 syz-executor.1 [30112] 0 30112 18146 13234 33 3 0 0 syz-executor.1 [30186] 0 30186 18146 13234 33 3 0 0 syz-executor.1 [30257] 0 30257 18146 13234 33 3 0 0 syz-executor.1 [30359] 0 30359 18146 13234 33 3 0 0 syz-executor.1 [30415] 0 30415 18146 13234 33 3 0 0 syz-executor.1 [30503] 0 30503 18146 13234 33 3 0 0 syz-executor.1 [30554] 0 30554 18146 13234 33 3 0 0 syz-executor.1 [30616] 0 30616 18146 13234 33 3 0 0 syz-executor.1 [30679] 0 30679 18179 8754 27 4 0 0 syz-executor.2 [30685] 0 30685 18146 13234 33 3 0 0 syz-executor.1 [30693] 0 30693 18113 8716 25 3 0 0 syz-executor.2 [30724] 0 30724 18179 8720 25 3 0 0 syz-executor.2 [30791] 0 30791 18146 13234 33 3 0 0 syz-executor.1 [30829] 0 30829 18146 13234 33 3 0 0 syz-executor.1 [30909] 0 30909 18146 13234 33 3 0 0 syz-executor.1 [30958] 0 30958 18146 13234 33 3 0 0 syz-executor.1 [31036] 0 31036 18146 13234 33 3 0 0 syz-executor.1 [31079] 0 31079 18146 13234 33 3 0 0 syz-executor.1 [31137] 0 31137 18146 13234 33 3 0 0 syz-executor.1 [31246] 0 31246 18146 13234 33 3 0 0 syz-executor.1 [31287] 0 31287 18146 13234 33 3 0 0 syz-executor.1 [31336] 0 31336 18146 13234 33 3 0 0 syz-executor.1 [31429] 0 31429 18146 13234 33 3 0 0 syz-executor.1 [31486] 0 31486 18146 13234 33 3 0 0 syz-executor.1 [31569] 0 31569 18146 13234 33 3 0 0 syz-executor.1 [31657] 0 31657 18146 13234 33 3 0 0 syz-executor.1 [31708] 0 31708 18146 13234 33 3 0 0 syz-executor.1 [31792] 0 31792 18146 13234 33 3 0 0 syz-executor.1 [31838] 0 31838 18146 13234 33 3 0 0 syz-executor.1 [31890] 0 31890 18146 13234 33 3 0 0 syz-executor.1 [31961] 0 31961 18146 13234 33 3 0 0 syz-executor.1 [31971] 0 31971 18113 8707 25 3 0 1000 syz-executor.4 [31977] 0 31977 18179 8711 25 3 0 1000 syz-executor.4 [32060] 0 32060 18146 13234 33 3 0 0 syz-executor.1 [32146] 0 32146 18146 13234 33 3 0 0 syz-executor.1