INFO: task syz.7.271:7167 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.271       state:D stack:27376 pid:7167  tgid:7166  ppid:6670   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x16e2/0x53f0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c0/0x12d0
 usbdev_open+0x151/0x770
 chrdev_open+0x4d9/0x600
 do_dentry_open+0x816/0x1380
 vfs_open+0x3b/0x340
 path_openat+0x2e3b/0x3890
 do_file_open+0x23e/0x4a0
 do_sys_openat2+0x113/0x200
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0x170/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb472b5e84e
RSP: 002b:00007fb473b0eb28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb473b0f6c0 RCX: 00007fb472b5e84e
RDX: 0000000000000002 RSI: 00007fb473b0ec00 RDI: ffffffffffffff9c
RBP: 00007fb473b0ec00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007fb472e26038 R14: 00007fb472e25fa0 R15: 00007ffd9faf1158
 </TASK>
INFO: task syz.5.275:7182 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.275       state:D stack:26360 pid:7182  tgid:7181  ppid:6086   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x16e2/0x53f0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c0/0x12d0
 usbdev_open+0x151/0x770
 chrdev_open+0x4d9/0x600
 do_dentry_open+0x816/0x1380
 vfs_open+0x3b/0x340
 path_openat+0x2e3b/0x3890
 do_file_open+0x23e/0x4a0
 do_sys_openat2+0x113/0x200
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0x170/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc93815e84e
RSP: 002b:00007fc939010b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fc9390116c0 RCX: 00007fc93815e84e
RDX: 0000000000000002 RSI: 00007fc939010c00 RDI: ffffffffffffff9c
RBP: 00007fc939010c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007fc938426038 R14: 00007fc938425fa0 R15: 00007ffe36ab4818
 </TASK>
INFO: task syz.6.291:7225 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.291       state:D stack:28240 pid:7225  tgid:7224  ppid:6362   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x16e2/0x53f0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7c0/0x12d0
 usbdev_open+0x151/0x770
 chrdev_open+0x4d9/0x600
 do_dentry_open+0x816/0x1380
 vfs_open+0x3b/0x340
 path_openat+0x2e3b/0x3890
 do_file_open+0x23e/0x4a0
 do_sys_openat2+0x113/0x200
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0x170/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f363cb5e84e
RSP: 002b:00007f363d9ddb28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f363d9de6c0 RCX: 00007f363cb5e84e
RDX: 0000000000000082 RSI: 00007f363d9ddc00 RDI: ffffffffffffff9c
RBP: 00007f363d9ddc00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007f363ce26038 R14: 00007f363ce25fa0 R15: 00007fffe5897ac8
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/0:0/9:
 #0: ffff88810006b148 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9bd/0x1470
 #1: ffffc900000e7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9bd/0x1470
 #2: ffff8881688e0240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1fd/0x3b0
1 lock held by khungtaskd/34:
 #0: ffffffff8e75d000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
3 locks held by kworker/0:2/883:
 #0: ffff88810006b148 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9bd/0x1470
 #1: ffffc90004a5fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9bd/0x1470
 #2: ffff888177a04240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1fd/0x3b0
3 locks held by kworker/1:3/5058:
 #0: ffff8881681fa148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9bd/0x1470
 #1: ffffc9000283fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9bd/0x1470
 #2: ffff88816f440198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4d30
1 lock held by dhcpcd/5337:
2 locks held by getty/5418:
 #0: ffff88810e8b20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x13a0
1 lock held by sshd/5532:
6 locks held by kworker/1:5/5701:
 #0: ffff8881681fa148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9bd/0x1470
 #1: ffffc9000691fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9bd/0x1470
 #2: ffff88816f560198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4d30
 #3: ffff8881686d0198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
 #4: ffff888168186160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450
 #5: ffffffff8e5fa630 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0x193/0x2c0
1 lock held by syz.7.271/7167:
 #0: ffff88816f560198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x151/0x770
1 lock held by syz.5.275/7182:
 #0: ffff88816f560198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x151/0x770
1 lock held by syz.6.291/7225:
 #0: ffff88816f560198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x151/0x770
1 lock held by udevd/8634:
2 locks held by syz-executor/10664:
3 locks held by syz-executor/10666:
2 locks held by syz-executor/10668:
3 locks held by syz.0.809/10942:

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xf9e/0xff0
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 10666 Comm: syz-executor Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__rcu_read_lock+0x2d/0x60
Code: fa 53 65 48 8b 1d 7b 0e 72 11 48 81 c3 c4 04 00 00 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 18 <ff> 03 8b 03 3d 00 00 00 40 7d 07 5b c3 cc cc cc cc cc 90 0f 0b 90
RSP: 0018:ffffc900061af360 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88816f5904c4 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff823b7f3a R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8e75d0c0 R12: ffffea0006746a80
R13: ffffea0006746a80 R14: ffffea0006746a88 R15: ffffea0006746a98
FS:  0000000000000000(0000) GS:ffff8882a9452000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056307b5a4131 CR3: 000000000e54c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 page_table_check_clear+0x13d/0x5f0
 unmap_page_range+0x3404/0x48f0
 unmap_vmas+0x462/0x680
 exit_mmap+0x292/0xa20
 __mmput+0x118/0x420
 exit_mm+0x160/0x210
 do_exit+0x6cd/0x2460
 do_group_exit+0x22d/0x2f0
 get_signal+0x121b/0x12c0
 arch_do_signal_or_restart+0xbb/0x810
 exit_to_user_mode_loop+0xa3/0x5e0
 do_syscall_64+0x357/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f986d359197
Code: Unable to access opcode bytes at 0x7f986d35916d.
RSP: 002b:00007fffd0bdbb50 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000555560f85500 RCX: 00007f986d359197
RDX: 0000000040000000 RSI: 00007fffd0bdbbac RDI: ffffffffffffffff
RBP: 00007fffd0bdbbac R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007fffd0bdbe08 R15: 0000000000000000
 </TASK>
