INFO: task kworker/0:1:25 blocked for more than 120 seconds. Not tainted 4.17.0-rc1+ #8 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:1 D19800 25 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 attempt to access beyond end of device loop7: rw=12288, want=8200, limit=20 kthread+0x345/0x410 kernel/kthread.c:238 attempt to access beyond end of device ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Showing all locks held in the system: 2 locks held by kworker/0:1/25: #0: loop7: rw=12288, want=12296, limit=20 0000000038607db1 ((wq_completion)"events"){+.+.}, at: __write_once_size include/linux/compiler.h:215 [inline] 0000000038607db1 ((wq_completion)"events"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] 0000000038607db1 ((wq_completion)"events"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] 0000000038607db1 ((wq_completion)"events"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:57 [inline] 0000000038607db1 ((wq_completion)"events"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] 0000000038607db1 ((wq_completion)"events"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] 0000000038607db1 ((wq_completion)"events"){+.+.}, at: process_one_work+0xaef/0x1b50 kernel/workqueue.c:2116 #1: 000000005be7b96b ((work_completion)(&wb->release_work)){+.+.}, at: process_one_work+0xb46/0x1b50 kernel/workqueue.c:2120 2 locks held by khungtaskd/892: #0: 000000006f7384d1 (rcu_read_lock){....}, at: check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: 000000006f7384d1 (rcu_read_lock){....}, at: watchdog+0x1ff/0xf60 kernel/hung_task.c:249 #1: 000000005b305b16 (tasklist_lock){.+.+}, at: debug_show_all_locks+0xde/0x34a kernel/locking/lockdep.c:4470 2 locks held by getty/4476: #0: 00000000954a1176 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000fc883528 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4477: #0: 0000000021997a96 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000a2e43a68 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4478: #0: 0000000098cabdf0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000003b50ccf4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4479: #0: 00000000526080ac (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000004a6f21a2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4480: #0: 0000000018b3ae8c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000d2a7c142 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4481: #0: 0000000030da5160 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000b9b1343f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4482: #0: 00000000aefea8f7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000bb52db47 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by syz-executor6/2194: #0: 00000000aff8d705 (&cpuctx_mutex){+.+.}, at: mutex_lock_double kernel/events/core.c:10300 [inline] #0: 00000000aff8d705 (&cpuctx_mutex){+.+.}, at: __perf_event_ctx_lock_double kernel/events/core.c:10360 [inline] #0: 00000000aff8d705 (&cpuctx_mutex){+.+.}, at: __do_sys_perf_event_open+0x19e2/0x3040 kernel/events/core.c:10619 #1: 000000008fa9428f (&cpuctx_mutex/1){+.+.}, at: mutex_lock_double kernel/events/core.c:10301 [inline] #1: 000000008fa9428f (&cpuctx_mutex/1){+.+.}, at: __perf_event_ctx_lock_double kernel/events/core.c:10360 [inline] #1: 000000008fa9428f (&cpuctx_mutex/1){+.+.}, at: __do_sys_perf_event_open+0x19f6/0x3040 kernel/events/core.c:10619 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 892 Comm: khungtaskd Not tainted 4.17.0-rc1+ #8 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 attempt to access beyond end of device 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 loop7: rw=12288, want=8200, limit=20 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2204 Comm: blkid Not tainted 4.17.0-rc1+ #8 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:update_stack_state+0x442/0x670 arch/x86/kernel/unwind_frame.c:218 RSP: 0018:ffff8801c710f5e0 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffff8801c710f810 RCX: ffff8801c710f7c0 RDX: 1ffff10038e21f09 RSI: ffff8801c710fc98 RDI: ffff8801c710f848 RBP: ffff8801c710f6e8 R08: ffff8801c710f848 R09: ffff8801ad544640 R10: ffffed0038e21f0c R11: ffff8801c710f867 R12: 1ffff10038e21ec4 R13: ffff8801c710fc98 R14: ffff8801c710f810 R15: ffff8801c710f860 FS: 0000000000000000(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f574916f4a0 CR3: 00000001cd446000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame.part.7+0x1a9/0x9c0 arch/x86/kernel/unwind_frame.c:329 unwind_next_frame+0x3e/0x50 arch/x86/kernel/unwind_frame.c:287 __save_stack_trace+0x6e/0xd0 arch/x86/kernel/stacktrace.c:44 save_stack_trace+0x1a/0x20 arch/x86/kernel/stacktrace.c:60 save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3554 __split_vma+0x11a/0x7f0 mm/mmap.c:2582 split_vma+0xa3/0xe0 mm/mmap.c:2645 mprotect_fixup+0x568/0x700 mm/mprotect.c:368 do_mprotect_pkey+0x56c/0xa10 mm/mprotect.c:506 __do_sys_mprotect mm/mprotect.c:531 [inline] __se_sys_mprotect mm/mprotect.c:528 [inline] __x64_sys_mprotect+0x78/0xb0 mm/mprotect.c:528 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f5748f67447 RSP: 002b:00007fffe9bc0348 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007f574916f4c8 RCX: 00007f5748f67447 RDX: 0000000000000000 RSI: 0000000000200000 RDI: 00007f5748d4d000 RBP: 00007fffe9bc0610 R08: 0000000000000003 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000206 R12: 00007fffe9bc06f8 R13: 0000000000000002 R14: 0000000000000030 R15: 00007fffe9bc0390 Code: 00 00 48 c7 85 28 ff ff ff 00 00 00 00 e9 0d fd ff ff 48 b8 00 00 00 00 00 fc ff df 49 8d 7e 38 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 1c 02 00 00 49 8b 46 38 48 83 c0 10 48 89 85 10 ff ff ff