INFO: task syz-executor.4:8033 blocked for more than 143 seconds. Not tainted 5.1.0-rc6+ #82 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D23576 8033 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 synchronize_rcu_expedited+0x431/0x5b0 kernel/rcu/tree_exp.h:775 namespace_unlock+0x108/0x130 fs/namespace.c:1384 do_umount fs/namespace.c:1605 [inline] ksys_umount+0x73e/0xf00 fs/namespace.c:1702 __do_sys_umount fs/namespace.c:1713 [inline] __se_sys_umount fs/namespace.c:1711 [inline] __x64_sys_umount+0x54/0x80 fs/namespace.c:1711 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45b7e7 Code: Bad RIP value. RSP: 002b:00007ffee9c952e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045b7e7 RDX: 00000000004032d0 RSI: 0000000000000002 RDI: 00007ffee9c95390 RBP: 0000000000007ff2 R08: 0000000000000000 R09: 000000000000000c R10: 0000000000000005 R11: 0000000000000206 R12: 00007ffee9c96420 R13: 0000000001189940 R14: 0000000000000000 R15: 00007ffee9c96420 INFO: task kworker/u4:7:14456 blocked for more than 143 seconds. Not tainted 5.1.0-rc6+ #82 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:7 D25072 14456 2 0x80000000 Workqueue: events_unbound fsnotify_connector_destroy_workfn Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_timeout+0x8ca/0xfd0 kernel/time/timer.c:1779 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 __synchronize_srcu+0x197/0x250 kernel/rcu/srcutree.c:925 synchronize_srcu+0x2dc/0x3e8 kernel/rcu/srcutree.c:1003 fsnotify_connector_destroy_workfn+0x4e/0xa0 fs/notify/mark.c:177 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task syz-executor.0:16461 blocked for more than 143 seconds. Not tainted 5.1.0-rc6+ #82 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D24176 16461 16457 0x00000000 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 exp_funnel_lock kernel/rcu/tree_exp.h:308 [inline] synchronize_rcu_expedited+0x54e/0x5b0 kernel/rcu/tree_exp.h:758 namespace_unlock+0x108/0x130 fs/namespace.c:1384 do_umount fs/namespace.c:1605 [inline] ksys_umount+0x73e/0xf00 fs/namespace.c:1702 __do_sys_umount fs/namespace.c:1713 [inline] __se_sys_umount fs/namespace.c:1711 [inline] __x64_sys_umount+0x54/0x80 fs/namespace.c:1711 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45b7e7 Code: Bad RIP value. RSP: 002b:00007ffe6ca4cc18 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045b7e7 RDX: 00000000004032d0 RSI: 0000000000000002 RDI: 00007ffe6ca4ccc0 RBP: 0000000000000a65 R08: 0000000000000000 R09: 000000000000000c R10: 0000000000000005 R11: 0000000000000202 R12: 00007ffe6ca4dd50 R13: 00000000014bf940 R14: 0000000000000000 R15: 00007ffe6ca4dd50 INFO: task syz-executor.1:16471 blocked for more than 144 seconds. Not tainted 5.1.0-rc6+ #82 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D24176 16471 16456 0x00000000 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 exp_funnel_lock kernel/rcu/tree_exp.h:317 [inline] synchronize_rcu_expedited+0x26f/0x5b0 kernel/rcu/tree_exp.h:758 namespace_unlock+0x108/0x130 fs/namespace.c:1384 do_umount fs/namespace.c:1605 [inline] ksys_umount+0x73e/0xf00 fs/namespace.c:1702 __do_sys_umount fs/namespace.c:1713 [inline] __se_sys_umount fs/namespace.c:1711 [inline] __x64_sys_umount+0x54/0x80 fs/namespace.c:1711 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45b7e7 Code: Bad RIP value. RSP: 002b:00007ffcce2e36f8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045b7e7 RDX: 00000000004032d0 RSI: 0000000000000002 RDI: 00007ffcce2e37a0 RBP: 00000000000055d7 R08: 0000000000000000 R09: 000000000000000c R10: 0000000000000005 R11: 0000000000000206 R12: 00007ffcce2e4830 R13: 0000000002894940 R14: 0000000000000000 R15: 00007ffcce2e4830 INFO: task kworker/u4:2:23394 blocked for more than 144 seconds. Not tainted 5.1.0-rc6+ #82 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:2 D25520 23394 2 0x80000000 Workqueue: events_unbound fsnotify_mark_destroy_workfn Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_timeout+0x8ca/0xfd0 kernel/time/timer.c:1779 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 __synchronize_srcu+0x197/0x250 kernel/rcu/srcutree.c:925 synchronize_srcu+0x2dc/0x3e8 kernel/rcu/srcutree.c:1003 fsnotify_mark_destroy_workfn+0x110/0x3b0 fs/notify/mark.c:827 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Showing all locks held in the system: 1 lock held by khungtaskd/1038: #0: 000000005eeacc0b (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5057 2 locks held by rs:main Q:Reg/7814: #0: 0000000084fa8d29 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 #1: 00000000262bbfe9 (sb_writers#4){.+.+}, at: file_start_write include/linux/fs.h:2825 [inline] #1: 00000000262bbfe9 (sb_writers#4){.+.+}, at: vfs_write+0x429/0x580 fs/read_write.c:548 1 lock held by rsyslogd/7816: #0: 000000009ba1dd6d (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/7938: #0: 00000000d79a163c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000d8f2992c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7939: #0: 00000000f935c4b2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e77f2bed (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7940: #0: 00000000c563b8f9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e44a215c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7941: #0: 000000002a00ead4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000fd49f973 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7942: #0: 000000003b42b7cb (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000bf5ff6a5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7943: #0: 00000000e65e2dac (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000a78cc3ca (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7944: #0: 0000000065d948a6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000f027bd5e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.4/8033: #0: 0000000072be12d0 (rcu_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:285 [inline] #0: 0000000072be12d0 (rcu_state.exp_mutex){+.+.}, at: synchronize_rcu_expedited+0x4ab/0x5b0 kernel/rcu/tree_exp.h:758 2 locks held by kworker/u4:7/14456: #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240 #1: 00000000f5a44f46 (connector_reaper_work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244 1 lock held by syz-executor.1/16471: #0: 0000000072be12d0 (rcu_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:317 [inline] #0: 0000000072be12d0 (rcu_state.exp_mutex){+.+.}, at: synchronize_rcu_expedited+0x26f/0x5b0 kernel/rcu/tree_exp.h:758 2 locks held by kworker/u4:2/23394: #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 00000000f048e97a ((wq_completion)events_unbound){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240 #1: 00000000d02222bd ((reaper_work).work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244 3 locks held by kworker/1:1/13755: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1038 Comm: khungtaskd Not tainted 5.1.0-rc6+ #82 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+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 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:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:288 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: