print_req_error: I/O error, dev nbd0, sector 64 isofs_fill_super: bread failed, dev=nbd0, iso_blknum=16, block=32 block nbd0: Attempted send on invalid socket print_req_error: I/O error, dev nbd0, sector 64 isofs_fill_super: bread failed, dev=nbd0, iso_blknum=16, block=32 INFO: task kworker/u4:1:21 blocked for more than 140 seconds. Not tainted 4.19.0-rc8-next-20181019+ #98 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:1 D12832 21 2 0x80000000 Workqueue: events_unbound fsnotify_mark_destroy_workfn Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3480 schedule+0xfe/0x460 kernel/sched/core.c:3524 schedule_timeout+0x1cc/0x260 kernel/time/timer.c:1780 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+0x427/0x8a0 kernel/sched/completion.c:136 __synchronize_srcu+0x20a/0x2d0 kernel/rcu/srcutree.c:941 synchronize_srcu+0x44c/0x5b0 kernel/rcu/srcutree.c:1019 fsnotify_mark_destroy_workfn+0x1be/0x510 fs/notify/mark.c:776 process_one_work+0xc8b/0x1c40 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task syz-executor4:10865 blocked for more than 140 seconds. Not tainted 4.19.0-rc8-next-20181019+ #98 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor4 D22760 10865 5707 0x80000004 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3480 schedule+0xfe/0x460 kernel/sched/core.c:3524 schedule_timeout+0x1cc/0x260 kernel/time/timer.c:1780 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+0x427/0x8a0 kernel/sched/completion.c:136 __synchronize_srcu+0x20a/0x2d0 kernel/rcu/srcutree.c:941 synchronize_srcu+0x44c/0x5b0 kernel/rcu/srcutree.c:1019 __mmu_notifier_release+0x379/0x630 mm/mmu_notifier.c:102 mmu_notifier_release include/linux/mmu_notifier.h:231 [inline] exit_mmap+0xa1/0x590 mm/mmap.c:3099 __mmput kernel/fork.c:1045 [inline] mmput+0x247/0x610 kernel/fork.c:1066 exit_mm kernel/exit.c:545 [inline] do_exit+0xe74/0x26d0 kernel/exit.c:854 do_group_exit+0x177/0x440 kernel/exit.c:970 get_signal+0x8a8/0x1970 kernel/signal.c:2517 do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x2e5/0x380 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: Bad RIP value. RSP: 002b:00007fb357432cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000072c048 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000072c048 RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000072c04c R13: 00007fffdca6ae5f R14: 00007fb3574339c0 R15: 0000000000000002 INFO: task syz-executor2:10905 blocked for more than 140 seconds. Not tainted 4.19.0-rc8-next-20181019+ #98 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D23336 10905 5623 0x00000006 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x8cf/0x21d0 kernel/sched/core.c:3480 schedule+0xfe/0x460 kernel/sched/core.c:3524 schedule_timeout+0x1cc/0x260 kernel/time/timer.c:1780 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+0x427/0x8a0 kernel/sched/completion.c:136 __synchronize_srcu+0x20a/0x2d0 kernel/rcu/srcutree.c:941 synchronize_srcu_expedited kernel/rcu/srcutree.c:966 [inline] synchronize_srcu+0x1d6/0x5b0 kernel/rcu/srcutree.c:1017 mmu_notifier_unregister+0x3b3/0x600 mm/mmu_notifier.c:381 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:745 [inline] kvm_put_kvm+0x6c0/0xff0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:770 kvm_vcpu_release+0x7b/0xa0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2413 __fput+0x3bc/0xa70 fs/file_table.c:279 ____fput+0x15/0x20 fs/file_table.c:312 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113 get_signal+0x1550/0x1970 kernel/signal.c:2347 do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x2e5/0x380 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: Bad RIP value. RSP: 002b:00007f3ebb652c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006 RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3ebb6536d4 R13: 00000000004c0027 R14: 00000000004d0108 R15: 00000000ffffffff Showing all locks held in the system: 3 locks held by kworker/1:0/17: 2 locks held by kworker/u4:1/21: #0: 00000000cdf3af44 ((wq_completion)"events_unbound"){+.+.}, at: __write_once_size include/linux/compiler.h:206 [inline] #0: 00000000cdf3af44 ((wq_completion)"events_unbound"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000cdf3af44 ((wq_completion)"events_unbound"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 00000000cdf3af44 ((wq_completion)"events_unbound"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 00000000cdf3af44 ((wq_completion)"events_unbound"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 00000000cdf3af44 ((wq_completion)"events_unbound"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 00000000cdf3af44 ((wq_completion)"events_unbound"){+.+.}, at: process_one_work+0xb43/0x1c40 kernel/workqueue.c:2124 #1: 00000000c4b6e45d ((reaper_work).work){+.+.}, at: process_one_work+0xb9a/0x1c40 kernel/workqueue.c:2128 1 lock held by khungtaskd/981: #0: 00000000785e46a7 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379 1 lock held by rsyslogd/5466: #0: 000000003724be0b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5556: #0: 00000000a03f9808 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000007bbc1886 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5557: #0: 00000000e023c141 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000085d5a520 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5558: #0: 000000000d49e45d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000843ba255 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5559: #0: 0000000074a944f7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000004a30eaa5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5560: #0: 000000003cd25bd3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000098e5eb0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5561: #0: 00000000500884a6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000043019435 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 2 locks held by getty/5562: #0: 00000000da608458 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000c04e2b5b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 981 Comm: khungtaskd Not tainted 4.19.0-rc8-next-20181019+ #98 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+0x244/0x39d lib/dump_stack.c:113 nmi_cpu_backtrace.cold.2+0x5c/0xa1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1e8/0x22a 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:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0xb39/0x1050 kernel/hung_task.c:265 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 17 Comm: kworker/1:0 Not tainted 4.19.0-rc8-next-20181019+ #98 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events rtc_timer_do_work RIP: 0010:debug_lockdep_rcu_enabled.part.3+0x2a/0x60 kernel/rcu/update.c:249 Code: 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 53 65 48 8b 1c 25 40 ee 01 00 48 8d bb 7c 08 00 00 48 89 fa 48 c1 ea 03 0f b6 14 02 <48> 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 10 8b 93 7c 08 00 RSP: 0018:ffff8801d9b3f370 EFLAGS: 00000a07 RAX: dffffc0000000000 RBX: ffff8801d9b2e480 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffffffff8539d8e3 RDI: ffff8801d9b2ecfc RBP: ffff8801d9b3f378 R08: ffff8801d9b2e480 R09: ffffed003b5e5b4f R10: ffffed003b5e5b4f R11: ffff8801daf2da7b R12: ffffffff89f2eae0 R13: dffffc0000000000 R14: ffff8801cbcc2ff8 R15: 155f83630b626e00 FS: 0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb12395f140 CR3: 00000001c404a000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_lockdep_rcu_enabled kernel/rcu/update.c:248 [inline] rcu_read_lock_sched_held+0x80/0x180 kernel/rcu/update.c:110 trace_rtc_timer_enqueue include/trace/events/rtc.h:182 [inline] rtc_timer_do_work+0xfd8/0x11a0 drivers/rtc/interface.c:924 process_one_work+0xc8b/0x1c40 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352