INFO: task syz-executor.4:4635 blocked for more than 143 seconds. Not tainted 5.9.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:29024 pid: 4635 ppid: 340 flags:0x80004006 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x889/0x1f70 kernel/sched/core.c:4527 schedule+0xcd/0x2b0 kernel/sched/core.c:4602 wdm_flush+0x2e9/0x3c0 drivers/usb/class/cdc-wdm.c:590 filp_close+0xb4/0x170 fs/open.c:1276 close_files fs/file.c:401 [inline] put_files_struct fs/file.c:429 [inline] put_files_struct+0x1d0/0x350 fs/file.c:426 exit_files+0x7e/0xa0 fs/file.c:458 do_exit+0xb75/0x2890 kernel/exit.c:801 do_group_exit+0x125/0x310 kernel/exit.c:903 get_signal+0x42d/0x1f10 kernel/signal.c:2757 arch_do_signal+0x88/0x1a00 arch/x86/kernel/signal.c:811 exit_to_user_mode_loop kernel/entry/common.c:135 [inline] exit_to_user_mode_prepare+0xf9/0x150 kernel/entry/common.c:166 syscall_exit_to_user_mode+0x36/0x260 kernel/entry/common.c:241 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: Bad RIP value. RSP: 002b:00007f962189acf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000118d088 RCX: 000000000045d5b9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000118d088 RBP: 000000000118d080 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118d08c R13: 00007ffdd269805f R14: 00007f962189b9c0 R15: 000000000118d08c INFO: task syz-executor.5:4627 blocked for more than 143 seconds. Not tainted 5.9.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:28816 pid: 4627 ppid: 338 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x889/0x1f70 kernel/sched/core.c:4527 schedule+0xcd/0x2b0 kernel/sched/core.c:4602 wdm_flush+0x2e9/0x3c0 drivers/usb/class/cdc-wdm.c:590 filp_close+0xb4/0x170 fs/open.c:1276 __close_fd+0x2f/0x50 fs/file.c:671 __do_sys_close fs/open.c:1295 [inline] __se_sys_close fs/open.c:1293 [inline] __x64_sys_close+0x69/0x100 fs/open.c:1293 do_syscall_64+0x2d/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x416f01 Code: Bad RIP value. RSP: 002b:00007ffee9c2dd20 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000416f01 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000001190780 R09: 0000000000000000 R10: 00007ffee9c2de00 R11: 0000000000000293 R12: 0000000001190788 R13: 0000000000000002 R14: ffffffffffffffff R15: 000000000118d08c Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: ffffffff87313620 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x264 kernel/locking/lockdep.c:5825 1 lock held by in:imklog/226: #0: ffff8881c7f19270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 2 locks held by agetty/233: #0: ffff8881d5350098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900009f22e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 23 Comm: khungtaskd Not tainted 5.9.0-rc1-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+0xf6/0x16e lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x74/0xb6 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1da/0x1f4 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd6a/0xfd0 kernel/hung_task.c:295 kthread+0x392/0x470 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 110 Comm: systemd-journal Not tainted 5.9.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:hlock_class kernel/locking/lockdep.c:174 [inline] RIP: 0010:__lock_acquire+0xb7d/0x5470 kernel/locking/lockdep.c:4423 Code: 85 a2 00 00 00 44 8b 4c 24 18 45 85 c9 0f 85 a2 07 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 54 24 20 48 c1 ea 03 0f b6 04 02 <84> c0 74 0e 3c 03 7f 0a 48 8b 7c 24 20 e8 c1 70 43 00 0f b7 5d 20 RSP: 0018:ffff8881d22cfa40 EFLAGS: 00000806 RAX: 0000000000000000 RBX: ffffffffffffffff RCX: ffffffff8126745f RDX: 1ffff1103a4fddb8 RSI: 00000000ffffffff RDI: ffffffff895c65e0 RBP: ffff8881d27eeda0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffff8881d22cff58 R12: 0000000000000000 R13: 0000000000000000 R14: ffff8881d27ee500 R15: 0000000000000001 FS: 00007f0fe4fde8c0(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0fe2502000 CR3: 00000001d201c000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x183/0x950 kernel/locking/lockdep.c:5005 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x32/0x50 kernel/locking/spinlock.c:159 debug_object_activate+0x12e/0x3e0 lib/debugobjects.c:636 debug_object_activate+0x337/0x3e0 lib/debugobjects.c:682 debug_rcu_head_queue kernel/rcu/rcu.h:176 [inline] __call_rcu kernel/rcu/tree.c:2880 [inline] call_rcu+0x2c/0xb90 kernel/rcu/tree.c:2968 task_work_run+0xdd/0x1a0 kernel/task_work.c:141 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:139 [inline] exit_to_user_mode_prepare+0x14d/0x150 kernel/entry/common.c:166 syscall_exit_to_user_mode+0x36/0x260 kernel/entry/common.c:241 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f0fe456e840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007fff6f4bb738 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: fffffffffffffffe RBX: 00007fff6f4bba40 RCX: 00007f0fe456e840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 000055a8a62fca90 RBP: 000000000000000d R08: 000000000000ffc0 R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 000055a8a62ef040 R14: 00007fff6f4bba00 R15: 000055a8a62fc3b0