INFO: task syz-executor.3:9837 can't die for more than 143 seconds. syz-executor.3 R running task 29024 9837 7299 0x00004006 Call Trace: Showing all locks held in the system: 1 lock held by khungtaskd/1169: #0: ffffffff899befc0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5754 1 lock held by in:imklog/6764: #0: ffff88809a3c9b70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 2 locks held by agetty/6989: #0: ffff8880a2fae098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc90000f942e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x220/0x1b30 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.3/9837: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1169 Comm: khungtaskd Not tainted 5.7.0-rc1-next-20200415-syzkaller #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+0x188/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x231/0x27e lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:249 [inline] watchdog+0xde3/0x14e0 kernel/hung_task.c:333 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9837 Comm: syz-executor.3 Not tainted 5.7.0-rc1-next-20200415-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline] RIP: 0010:lock_is_held_type+0x251/0x350 kernel/locking/lockdep.c:4973 Code: 00 00 83 ab cc 08 00 00 01 75 5d 48 c7 c0 e0 c4 94 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 c2 00 00 00 <48> 83 3d 37 1a 3c 08 00 74 32 48 8b 7c 24 10 57 9d 0f 1f 44 00 00 RSP: 0018:ffffc90001927b90 EFLAGS: 00000046 RAX: 1ffffffff132989c RBX: ffff888092c3a5c0 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 1ffff110125875d1 RDI: ffff888092c3ae8c RBP: ffff888092c3a5c0 R08: ffffffff81be5df0 R09: ffffed1011eca081 R10: ffffc90001927d98 R11: ffffed1011eca080 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff888092c3ae88 R15: ffffffff899bef00 FS: 00007f60aa639700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9a4f69d000 CR3: 000000002afd4000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:406 [inline] ___might_sleep+0x1fc/0x2b0 kernel/sched/core.c:6771 __mutex_lock_common kernel/locking/mutex.c:935 [inline] __mutex_lock+0xc5/0x13c0 kernel/locking/mutex.c:1103 pipe_lock_nested fs/pipe.c:66 [inline] pipe_double_lock+0x1a0/0x1e0 fs/pipe.c:104 splice_pipe_to_pipe fs/splice.c:1562 [inline] do_splice+0x377/0x1560 fs/splice.c:1141 __do_sys_splice fs/splice.c:1447 [inline] __se_sys_splice fs/splice.c:1427 [inline] __x64_sys_splice+0x2c1/0x330 fs/splice.c:1427 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45ca29 Code: 0d 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 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f60aa638c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 00000000005079c0 RCX: 000000000045ca29 RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 000000000078c220 R08: 0000000000010000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000bae R14: 00000000004ce9f7 R15: 00007f60aa6396d4