INFO: task syz-executor3:7623 blocked for more than 140 seconds. Not tainted 4.19.0-rc2-next-20180904+ #55 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D24952 7623 4309 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x87c/0x1df0 kernel/sched/core.c:3473 schedule+0xfb/0x450 kernel/sched/core.c:3517 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3575 __mutex_lock_common kernel/locking/mutex.c:1003 [inline] __mutex_lock+0xbf9/0x1700 kernel/locking/mutex.c:1073 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088 snd_seq_ioctl+0x221/0x440 sound/core/seq/seq_clientmgr.c:2137 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702 __do_sys_ioctl fs/ioctl.c:709 [inline] __se_sys_ioctl fs/ioctl.c:707 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457099 Code: 48 8b 54 24 38 48 8b 7c 24 48 eb 8d 48 8b 6c 24 50 48 83 c4 58 c3 48 89 04 24 48 89 5c 24 08 e8 fd a8 fb ff 48 8b 44 24 40 48 <8b> 4c 24 48 48 8b 54 24 38 4c 8b 54 24 18 e9 ee fe ff ff 48 89 74 RSP: 002b:00007f3bab83ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f3bab83b6d4 RCX: 0000000000457099 RDX: 00000000200000c0 RSI: 00000000c08c5332 RDI: 000000000000000b RBP: 00000000009301e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d0918 R14: 00000000004bf1b8 R15: 0000000000000002 INFO: task syz-executor3:7626 blocked for more than 140 seconds. Not tainted 4.19.0-rc2-next-20180904+ #55 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D25528 7626 4309 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x87c/0x1df0 kernel/sched/core.c:3473 schedule+0xfb/0x450 kernel/sched/core.c:3517 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3575 __mutex_lock_common kernel/locking/mutex.c:1003 [inline] __mutex_lock+0xbf9/0x1700 kernel/locking/mutex.c:1073 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088 snd_seq_ioctl+0x221/0x440 sound/core/seq/seq_clientmgr.c:2137 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702 __do_sys_ioctl fs/ioctl.c:709 [inline] __se_sys_ioctl fs/ioctl.c:707 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457099 Code: 48 8b 54 24 38 48 8b 7c 24 48 eb 8d 48 8b 6c 24 50 48 83 c4 58 c3 48 89 04 24 48 89 5c 24 08 e8 fd a8 fb ff 48 8b 44 24 40 48 <8b> 4c 24 48 48 8b 54 24 38 4c 8b 54 24 18 e9 ee fe ff ff 48 89 74 RSP: 002b:00007f3bab819c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f3bab81a6d4 RCX: 0000000000457099 RDX: 0000000020000380 RSI: 0000000040505331 RDI: 0000000000000005 RBP: 0000000000930280 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d0bb8 R14: 00000000004bf610 R15: 0000000000000003 Showing all locks held in the system: 1 lock held by khungtaskd/792: #0: 0000000094cfbf31 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4436 1 lock held by rsyslogd/4168: 2 locks held by getty/4259: #0: 0000000047b3391d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000002066990d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4260: #0: 000000009fa374f5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000aee6bd0a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4261: #0: 000000007c11e3f7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000d3e40d17 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4262: #0: 00000000bcd66c6f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000005b62dc77 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4263: #0: 0000000096228e45 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000008fc88d80 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4264: #0: 0000000022f53615 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000ecf46ca8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4265: #0: 000000003c93d6b3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000002954ca07 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 3 locks held by kworker/u4:4/6529: #0: 000000002fafc136 ((wq_completion)"%s""netns"){+.+.}, at: __write_once_size include/linux/compiler.h:215 [inline] #0: 000000002fafc136 ((wq_completion)"%s""netns"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000002fafc136 ((wq_completion)"%s""netns"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 000000002fafc136 ((wq_completion)"%s""netns"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 000000002fafc136 ((wq_completion)"%s""netns"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 000000002fafc136 ((wq_completion)"%s""netns"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 000000002fafc136 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0xb44/0x1aa0 kernel/workqueue.c:2124 #1: 000000008f3a4e21 (net_cleanup_work){+.+.}, at: process_one_work+0xb9b/0x1aa0 kernel/workqueue.c:2128 #2: 00000000e1417b03 (pernet_ops_rwsem){++++}, at: cleanup_net+0x13f/0xb60 net/core/net_namespace.c:518 3 locks held by syz-executor3/7595: 1 lock held by syz-executor3/7623: #0: 00000000ea002473 (&client->ioctl_mutex){+.+.}, at: snd_seq_ioctl+0x221/0x440 sound/core/seq/seq_clientmgr.c:2137 1 lock held by syz-executor3/7626: #0: 00000000ea002473 (&client->ioctl_mutex){+.+.}, at: snd_seq_ioctl+0x221/0x440 sound/core/seq/seq_clientmgr.c:2137 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 792 Comm: khungtaskd Not tainted 4.19.0-rc2-next-20180904+ #55 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+0x1c9/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.3+0x48/0x88 lib/nmi_backtrace.c:101 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:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0xb39/0x1040 kernel/hung_task.c:265 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.552 msecs NMI backtrace for cpu 0 CPU: 0 PID: 7595 Comm: syz-executor3 Not tainted 4.19.0-rc2-next-20180904+ #55 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:perf_swevent_hrtimer+0x422/0x510 kernel/events/core.c:9100 Code: bf 00 00 00 49 8b 46 50 e8 db 5b 6c 05 4c 89 ea 48 89 df 48 89 c6 e8 2d e8 d6 ff e8 38 c2 e8 ff 48 b8 00 00 00 00 00 fc ff df <49> c7 04 04 00 00 00 00 44 89 f8 48 8b 8c 24 38 02 00 00 65 48 33 RSP: 0018:ffff8801db007180 EFLAGS: 00000006 RAX: dffffc0000000000 RBX: ffff8801d18c8318 RCX: ffffffff816afe30 RDX: 0000000000010100 RSI: ffffffff81941438 RDI: 0000000000000006 RBP: ffff8801db007408 R08: ffff880185720580 R09: ffffffff88f7d01b R10: fffffbfff11efa01 R11: 0000000000000000 R12: 1ffff1003b600e38 R13: 0000000000002710 R14: ffff8801db025d40 R15: 0000000000000001 FS: 00007f3bab87d700(0000) GS:ffff8801db000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020c00000 CR3: 00000001d73dc000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1398 [inline] __hrtimer_run_queues+0x3eb/0xff0 kernel/time/hrtimer.c:1460 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline] smp_apic_timer_interrupt+0x16d/0x6a0 arch/x86/kernel/apic/apic.c:1054 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:867 RIP: 0010:arch_local_irq_enable arch/x86/include/asm/paravirt.h:798 [inline] RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] RIP: 0010:_raw_spin_unlock_irq+0x56/0x70 kernel/locking/spinlock.c:192 Code: 11 88 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 1d 48 83 3d eb de 3a 01 00 74 11 fb 66 0f 1f 44 00 00 <65> ff 0d 33 0e 2b 79 5b 5d c3 0f 0b e8 a9 12 e5 fa eb dc 0f 1f 80 RSP: 0018:ffff8801db007970 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: ffff8801db023740 RCX: 1ffff10030ae41bc RDX: 1ffffffff10237cf RSI: 0000000000000000 RDI: ffffffff8811be78 RBP: ffff8801db007978 R08: ffff880185720dc0 R09: 0000000000000002 R10: ffff880185720580 R11: 0000000000000000 R12: 000000010001c042 R13: dffffc0000000000 R14: ffff8801db007c50 R15: 00000000ffffffff __run_timers+0x9c8/0xc60 kernel/time/timer.c:1685 run_timer_softirq+0x1d/0x40 kernel/time/timer.c:1695 __do_softirq+0x2eb/0xa74 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x1d6/0x210 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x18e/0x6a0 arch/x86/kernel/apic/apic.c:1056 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:867 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:788 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa1/0xc0 kernel/locking/spinlock.c:184 Code: 68 be 11 88 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 21 48 83 3d 3e da 3a 01 00 74 0e 48 89 df 57 9d <0f> 1f 44 00 00 eb bb 0f 0b 0f 0b e8 0f 0e e5 fa eb 97 e8 08 0e e5 RSP: 0018:ffff880188667878 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 0000000000000286 RCX: 1ffff10030ae41bc RDX: 1ffffffff10237cd RSI: 0000000000000000 RDI: 0000000000000286 RBP: ffff880188667888 R08: ffff880185720dc0 R09: 0000000000000006 R10: ffff880185720580 R11: 0000000000000000 R12: ffff8801c7f1da98 R13: ffff8801cf559b0c R14: ffff8801c7f1da98 R15: 0000000000000286 spin_unlock_irqrestore include/linux/spinlock.h:384 [inline] snd_seq_prioq_cell_out+0x1e3/0x350 sound/core/seq/seq_prioq.c:253 snd_seq_check_queue.part.4+0x1a6/0x360 sound/core/seq/seq_queue.c:280 snd_seq_check_queue sound/core/seq/seq_queue.c:255 [inline] snd_seq_enqueue_event+0x346/0x4d0 sound/core/seq/seq_queue.c:343 snd_seq_client_enqueue_event+0x2a5/0x510 sound/core/seq/seq_clientmgr.c:957 snd_seq_write+0x3f1/0x8d0 sound/core/seq/seq_clientmgr.c:1074 __vfs_write+0x117/0x9d0 fs/read_write.c:485 vfs_write+0x1fc/0x560 fs/read_write.c:549 ksys_write+0x101/0x260 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457099 Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f3bab87cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f3bab87d6d4 RCX: 0000000000457099 RDX: 00000000ffffff76 RSI: 0000000020000000 RDI: 0000000000000005 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d8400 R14: 00000000004cae90 R15: 0000000000000000