Option ' A+ɚ8ߥ2wkt/?ܘKkK֩S7 $WetѪ#`Ip;fA憰d'"XCp_Jᔇ+7 t 5@1I SvvD73 aH@=CO%P*B\~>q&6s7)@' to dns_resolver key: bad/missing value INFO: task kworker/0:2:2105 blocked for more than 120 seconds. Not tainted 4.17.0-rc2+ #17 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:2 D19800 2105 2 0x80000000 Workqueue: events cgwb_release_workfn Call Trace: context_switch kernel/sched/core.c:2848 [inline] __schedule+0x801/0x1e30 kernel/sched/core.c:3490 schedule+0xef/0x430 kernel/sched/core.c:3549 bit_wait+0x18/0x90 kernel/sched/wait_bit.c:197 __wait_on_bit+0xb3/0x130 kernel/sched/wait_bit.c:48 out_of_line_wait_on_bit+0x204/0x3a0 kernel/sched/wait_bit.c:63 wait_on_bit include/linux/wait_bit.h:76 [inline] wb_shutdown+0x370/0x470 mm/backing-dev.c:366 cgwb_release_workfn+0x87/0x750 mm/backing-dev.c:509 process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145 worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279 kthread+0x345/0x410 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Showing all locks held in the system: 2 locks held by khungtaskd/892: #0: 00000000ed2b4010 (rcu_read_lock){....}, at: check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: 00000000ed2b4010 (rcu_read_lock){....}, at: watchdog+0x1ff/0xf60 kernel/hung_task.c:249 #1: 000000001b5da285 (tasklist_lock){.+.?}, at: debug_show_all_locks+0xde/0x34a kernel/locking/lockdep.c:4470 2 locks held by kworker/0:2/2105: #0: 00000000abd49cb1 ((wq_completion)"events"){+.+.}, at: __write_once_size include/linux/compiler.h:215 [inline] #0: 00000000abd49cb1 ((wq_completion)"events"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000abd49cb1 ((wq_completion)"events"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 00000000abd49cb1 ((wq_completion)"events"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:57 [inline] #0: 00000000abd49cb1 ((wq_completion)"events"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 00000000abd49cb1 ((wq_completion)"events"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 00000000abd49cb1 ((wq_completion)"events"){+.+.}, at: process_one_work+0xaef/0x1b50 kernel/workqueue.c:2116 #1: 0000000004c06750 ((work_completion)(&wb->release_work)){+.+.}, at: process_one_work+0xb46/0x1b50 kernel/workqueue.c:2120 2 locks held by rs:main Q:Reg/4431: #0: 00000000cb4d8cf7 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1a9/0x1e0 fs/file.c:766 #1: 00000000873cd018 (sb_writers#4){++++}, at: file_start_write include/linux/fs.h:2718 [inline] #1: 00000000873cd018 (sb_writers#4){++++}, at: vfs_write+0x452/0x560 fs/read_write.c:548 2 locks held by getty/4524: #0: 0000000059c54fba (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000b09a9fbc (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4525: #0: 00000000936af44e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000005578c83d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4526: #0: 0000000026c24815 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000a016ba33 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4527: #0: 00000000530b2ab0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000009d56159b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4528: #0: 000000004a9253b1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000893c74d4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4529: #0: 00000000f77e4df7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000002706348a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4530: #0: 00000000f6f1974a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000001f304921 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 1 lock held by syz-executor2/4599: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor1/4600: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor7/4602: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor3/4601: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor5/4603: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor0/16057: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor4/18610: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor4/18617: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor4/18620: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor4/18621: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 2 locks held by syz-executor4/18622: #0: 00000000cb9cc81f (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1a9/0x1e0 fs/file.c:766 #1: 00000000873cd018 (sb_writers#4){++++}, at: file_start_write include/linux/fs.h:2718 [inline] #1: 00000000873cd018 (sb_writers#4){++++}, at: vfs_write+0x452/0x560 fs/read_write.c:548 1 lock held by syz-executor4/18623: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor4/18624: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 1 lock held by syz-executor6/18618: #0: 00000000873cd018 (sb_writers#4){++++}, at: sb_start_write include/linux/fs.h:1550 [inline] #0: 00000000873cd018 (sb_writers#4){++++}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 892 Comm: khungtaskd Not tainted 4.17.0-rc2+ #17 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline] check_hung_task kernel/hung_task.c:132 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] watchdog+0xc10/0xf60 kernel/hung_task.c:249 kthread+0x345/0x410 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54