INFO: task syz-executor.4:18482 can't die for more than 143 seconds. syz-executor.4 R running task 27160 18482 30115 0x00004006 Call Trace: Showing all locks held in the system: 1 lock held by khungtaskd/1065: #0: ffffffff88fa7f00 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5337 1 lock held by rsyslogd/8659: #0: ffff8880a4d0ae20 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8751: #0: ffff8880a1ef2090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f392e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8752: #0: ffff8880a7509090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f192e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8753: #0: ffff888096497090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f252e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8754: #0: ffff88809663c090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8755: #0: ffff888090d73090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8756: #0: ffff888091e1a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f2d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8757: #0: ffff88809988a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f012e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.4/18482: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1065 Comm: khungtaskd Not tainted 5.3.0-rc6-next-20190830 #75 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+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b 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:269 [inline] watchdog+0xc99/0x1360 kernel/hung_task.c:353 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 18482 Comm: syz-executor.4 Not tainted 5.3.0-rc6-next-20190830 #75 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__kasan_check_read+0x1/0x20 mm/kasan/common.c:92 Code: c9 8f 05 8b 5d c4 e9 c5 9d ff ff 48 8b 73 58 89 c2 48 c7 c7 90 db a7 88 f7 da e8 7e d7 ae ff e9 0e ef ff ff 90 90 90 90 90 55 <89> f6 31 d2 48 89 e5 48 8b 4d 08 e8 cf 26 00 00 5d c3 0f 1f 00 66 RSP: 0018:ffff8880ae809d60 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 1ffff11015d013b3 RCX: ffffffff815840f2 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff89c577c0 RBP: ffff8880ae809e40 R08: 0000000000005565 R09: fffffbfff14ed32d R10: ffff88806c5a4c48 R11: ffff88806c5a4380 R12: ffffffff88fb6e08 R13: ffffffff8165a1aa R14: ffff8880ae809e18 R15: 0000000000000000 FS: 00007ff083978700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020e00000 CR3: 000000009b96f000 CR4: 00000000001406f0 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 kernel/time/timekeeping.c:757 [inline] ktime_get+0xe7/0x300 kernel/time/timekeeping.c:747 clockevents_program_event+0x15a/0x370 kernel/time/clockevents.c:326 tick_program_event+0xb4/0x130 kernel/time/tick-oneshot.c:44 hrtimer_interrupt+0x369/0x770 kernel/time/hrtimer.c:1641 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1106 [inline] smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1131 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 RIP: 0010:__might_sleep+0x3a/0x190 kernel/sched/core.c:6625 Code: 41 89 d6 41 55 41 89 f5 41 54 49 89 fc 53 65 48 8b 1c 25 40 fe 01 00 48 8d 7b 10 48 83 ec 10 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 0e 01 00 00 48 8b 43 10 48 85 c0 74 3e 65 48 8b 1c 25 40 fe RSP: 0018:ffff888070d97bf0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: ffff88806c5a4380 RCX: ffffc9000a1d0000 RDX: 1ffff1100d8b4872 RSI: 000000000000000a RDI: ffff88806c5a4390 RBP: ffff888070d97c20 R08: ffff88806c5a4380 R09: ffffed1014686fb1 R10: ffffed1014686fb0 R11: ffff8880a3437d83 R12: ffffffff87e63460 R13: 000000000000000a R14: 0000000000000000 R15: ffff888070d97d80 __might_fault+0xc6/0x1e0 mm/memory.c:4453 _copy_from_user+0x30/0x1a0 lib/usercopy.c:10 copy_from_user include/linux/uaccess.h:144 [inline] snd_seq_write+0x49c/0x740 sound/core/seq/seq_clientmgr.c:1052 __vfs_write+0x8a/0x110 fs/read_write.c:494 vfs_write+0x268/0x5d0 fs/read_write.c:558 ksys_write+0x220/0x290 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:620 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459879 Code: fd b7 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 b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff083977c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459879 RDX: 00000000ffffff76 RSI: 0000000020000000 RDI: 0000000000000005 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff0839786d4 R13: 00000000004c9b5e R14: 00000000004e12a8 R15: 00000000ffffffff