INFO: task syz-executor.5:15720 blocked for more than 143 seconds. Not tainted 5.4.0-rc6+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29208 15720 7155 0x00004006 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x8ca/0x19f0 kernel/sched/core.c:4069 schedule+0xc0/0x260 kernel/sched/core.c:4136 perf_event_free_task+0x43f/0x630 kernel/events/core.c:11701 copy_process+0x3616/0x6450 kernel/fork.c:2278 _do_fork+0xec/0xbe0 kernel/fork.c:2366 __do_sys_clone kernel/fork.c:2521 [inline] __se_sys_clone kernel/fork.c:2502 [inline] __x64_sys_clone+0x17c/0x230 kernel/fork.c:2502 do_syscall_64+0xd0/0x5e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c29 Code: 20 f3 44 0f 7f 40 30 f3 44 0f 7f 48 40 f3 44 0f 7f 50 50 f3 44 0f 7f 58 60 f3 44 0f 7f 60 70 c3 48 81 eb 80 00 00 00 0f 18 86 <40> fe ff ff 0f 18 86 80 fd ff ff c5 fe 6f 46 e0 c5 fe 6f 4e c0 c5 RSP: 002b:00007ff07c527c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000458c29 RDX: 9999999999999999 RSI: 0000000000000000 RDI: 0000002102001ff9 RBP: 000000000073bf00 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff07c5286d4 R13: 00000000004befd3 R14: 00000000004d0020 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1057: #0: ffffffff883a45c0 (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:5337 1 lock held by rsyslogd/6945: 2 locks held by getty/7035: #0: ffff88808df0b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f212e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1930 drivers/tty/n_tty.c:2156 2 locks held by getty/7036: #0: ffff8880970d3090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f252e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1930 drivers/tty/n_tty.c:2156 2 locks held by getty/7037: #0: ffff8880a145c090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f152e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1930 drivers/tty/n_tty.c:2156 2 locks held by getty/7038: #0: ffff888094c52090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f192e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1930 drivers/tty/n_tty.c:2156 2 locks held by getty/7039: #0: ffff88808a942090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f1d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1930 drivers/tty/n_tty.c:2156 2 locks held by getty/7040: #0: ffff88809763c090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1930 drivers/tty/n_tty.c:2156 2 locks held by getty/7041: #0: ffff88809b1fb090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005ef12e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1930 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1057 Comm: khungtaskd Not tainted 5.4.0-rc6+ #0 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+0x12d/0x187 lib/dump_stack.c:118 nmi_cpu_backtrace.cold.7+0x4b/0x84 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x18b/0x1b7 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:205 [inline] watchdog+0x592/0xb70 kernel/hung_task.c:289 kthread+0x334/0x3f0 kernel/kthread.c:255 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 skipped: idling at native_safe_halt+0x12/0x20 arch/x86/include/asm/irqflags.h:60