INFO: task syz-executor1:24841 blocked for more than 140 seconds. Not tainted 4.19.0-rc4+ #248 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D24240 24841 23438 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3575 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0xbe7/0x1700 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 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: 0033:0x457679 Code: Bad RIP value. RSP: 002b:00007fbee2131c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fbee21326d4 RCX: 0000000000457679 RDX: 00000000200000c0 RSI: 00000000c08c5332 RDI: 000000000000000c RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d1260 R14: 00000000004c8c28 R15: 0000000000000001 INFO: task syz-executor1:24890 blocked for more than 140 seconds. Not tainted 4.19.0-rc4+ #248 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D25544 24890 23438 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3575 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0xbe7/0x1700 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 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: 0033:0x457679 Code: Bad RIP value. RSP: 002b:00007fbee20efc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fbee20f06d4 RCX: 0000000000457679 RDX: 0000000020000000 RSI: 0000000040bc5311 RDI: 000000000000000c RBP: 000000000072c0e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d1428 R14: 00000000004c8f18 R15: 0000000000000003 INFO: task syz-executor1:24891 blocked for more than 140 seconds. Not tainted 4.19.0-rc4+ #248 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor1 D25880 24891 23438 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3575 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0xbe7/0x1700 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 snd_seq_write+0x1f1/0x8d0 sound/core/seq/seq_clientmgr.c:1021 __vfs_write+0x119/0x9f0 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: 0033:0x457679 Code: Bad RIP value. RSP: 002b:00007fbee20cec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fbee20cf6d4 RCX: 0000000000457679 RDX: 00000000ffffffbd RSI: 0000000020042f70 RDI: 000000000000000c RBP: 000000000072c180 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d8d48 R14: 00000000004c5644 R15: 0000000000000004 Showing all locks held in the system: 1 lock held by khungtaskd/984: #0: 00000000e33920bc (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4435 1 lock held by rsyslogd/5216: #0: 000000004e57ec74 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5305: #0: 00000000c2681ac0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000020033e12 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5306: #0: 00000000ac257759 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000e9c93a45 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5307: #0: 00000000ff2ca067 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000022482abf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5308: #0: 0000000068b4a993 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000007fc1fc48 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5309: #0: 0000000045dc7b65 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000ce8fb3a2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5310: #0: 0000000072d01964 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000318aaab1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5311: #0: 00000000244dcf19 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000dda9f269 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 1 lock held by syz-executor1/24829: 1 lock held by syz-executor1/24841: #0: 00000000670503a7 (&client->ioctl_mutex){+.+.}, at: snd_seq_ioctl+0x221/0x440 sound/core/seq/seq_clientmgr.c:2137 1 lock held by syz-executor1/24890: #0: 00000000670503a7 (&client->ioctl_mutex){+.+.}, at: snd_seq_ioctl+0x221/0x440 sound/core/seq/seq_clientmgr.c:2137 1 lock held by syz-executor1/24891: #0: 00000000670503a7 (&client->ioctl_mutex){+.+.}, at: snd_seq_write+0x1f1/0x8d0 sound/core/seq/seq_clientmgr.c:1021 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 984 Comm: khungtaskd Not tainted 4.19.0-rc4+ #248 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+0x1c4/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed 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+0xb3e/0x1050 kernel/hung_task.c:265 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 0 to CPUs 1: INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.359 msecs NMI backtrace for cpu 1 CPU: 1 PID: 24829 Comm: syz-executor1 Not tainted 4.19.0-rc4+ #248 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_release kernel/locking/lockdep.c:3697 [inline] RIP: 0010:lock_release+0x3b3/0x970 kernel/locking/lockdep.c:3919 Code: ff 48 c1 ee 03 0f b6 0c 0e 84 c9 74 09 80 f9 03 0f 8e 0f 05 00 00 48 89 c6 41 89 97 78 08 00 00 48 b9 00 00 00 00 00 fc ff df <48> c1 ee 03 80 3c 0e 00 0f 85 18 05 00 00 49 8d bf 70 08 00 00 4c RSP: 0018:ffff8801daf07b38 EFLAGS: 00000046 RAX: ffff88018e6f0f28 RBX: 1ffff1003b5e0f6b RCX: dffffc0000000000 RDX: 0000000000000001 RSI: ffff88018e6f0f28 RDI: ffff88018e6f0f4a RBP: ffff8801daf07c60 R08: ffff88018e6f0680 R09: 0000000000000001 R10: ffff88018e6f0f28 R11: 05bc14afc5dd28c2 R12: ffff8801daf07b78 R13: ffff8801daf07c38 R14: 0000000000000002 R15: ffff88018e6f0680 FS: 00007fbee2153700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001bdb4a000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: seqcount_lockdep_reader_access include/linux/seqlock.h:82 [inline] read_seqcount_begin include/linux/seqlock.h:164 [inline] ktime_get+0x163/0x440 kernel/time/timekeeping.c:754 clockevents_program_event+0x158/0x370 kernel/time/clockevents.c:336 tick_program_event+0xb7/0x130 kernel/time/tick-oneshot.c:48 hrtimer_interrupt+0x368/0x780 kernel/time/hrtimer.c:1531 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline] smp_apic_timer_interrupt+0x1a1/0x760 arch/x86/kernel/apic/apic.c:1054 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864 RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:783 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:805 [inline] RIP: 0010:__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] RIP: 0010:_raw_spin_lock_irqsave+0x2c/0xd0 kernel/locking/spinlock.c:152 Code: 00 00 00 00 00 fc ff df 55 48 89 e5 41 54 53 48 89 fb 48 c7 c7 e0 29 52 89 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 85 00 00 00 <48> 83 3d cc 68 92 01 00 74 77 9c 58 0f 1f 44 00 00 48 c7 c7 f0 29 RSP: 0018:ffff88019232f548 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: ffff8801c1406830 RCX: ffffc90003c5f000 RDX: 1ffffffff12a453c RSI: ffffffff85ee82f2 RDI: ffffffff895229e0 RBP: ffff88019232f558 R08: ffff88018e6f0680 R09: 0000000000000006 R10: 0000000000000000 R11: ffff88018e6f0680 R12: ffff8801c1406830 R13: ffffc90002351d9c R14: ffff8801c1406940 R15: 0000000000000000 queue_access_unlock sound/core/seq/seq_queue.c:379 [inline] snd_seq_control_queue+0x1ae/0x680 sound/core/seq/seq_queue.c:739 event_input_timer+0x25/0x30 sound/core/seq/seq_system.c:118 snd_seq_deliver_single_event.constprop.17+0x897/0xa30 sound/core/seq/seq_clientmgr.c:621 snd_seq_deliver_event+0x5a4/0xaa0 sound/core/seq/seq_clientmgr.c:822 snd_seq_dispatch_event+0x129/0x660 sound/core/seq/seq_clientmgr.c:896 snd_seq_check_queue.part.4+0x139/0x360 sound/core/seq/seq_queue.c:275 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+0x119/0x9f0 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: 0033:0x457679 Code: 1d 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 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fbee2152c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fbee21536d4 RCX: 0000000000457679 RDX: 00000000ffffffbd RSI: 0000000020042f70 RDI: 0000000000000005 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d8d48 R14: 00000000004c5644 R15: 0000000000000000