INFO: task syz.5.99:6578 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.99        state:D stack:24960 pid:6578  tgid:6576  ppid:6414   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x61e/0x920
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x290
 __se_sys_quotactl+0x3a7/0x9e0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fefe099c799
RSP: 002b:00007fefe17f3028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fefe0c15fa0 RCX: 00007fefe099c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100
RBP: 00007fefe0a32c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fefe0c16038 R14: 00007fefe0c15fa0 R15: 00007ffc68767468
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/u8:0/12:
 #0: ffff888171d36148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830
 #1: ffffc90000117c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830
 #2: ffffffff8fbccd88 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11e/0x14c0
1 lock held by khungtaskd/35:
 #0: ffffffff8e75e420 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5633:
 #0: ffff8881144500a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
2 locks held by syz-executor/5808:
4 locks held by kworker/u8:2/5821:
 #0: ffff8881012ae148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830
 #1: ffffc90006067c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830
 #2: ffffffff8fbbe5f0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800
 #3: ffffffff8fbccd88 (rtnl_mutex){+.+.}-{4:4}, at: wg_destruct+0x25/0x310
1 lock held by syz.5.99/6578:
 #0: ffff8881ba4080e0 (&type->s_umount_key#68){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.4.173/7177:
 #0: ffff8881ba4080e0 (&type->s_umount_key#68){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
3 locks held by kworker/0:6/8869:
 #0: ffff88810006b148 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830
 #1: ffffc90006d9fc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830
 #2: ffff8881b9611240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x202/0x3d0
1 lock held by syz.1.429/9077:
 #0: ffff8881ba4080e0 (&type->s_umount_key#68){++++}-{4:4}, at: super_lock+0x289/0x3d0
1 lock held by syz-executor/10023:
 #0: ffffffff8fbccd88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0
9 locks held by syz-executor/10040:
 #0: ffff8881145fe420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90
 #1: ffff88816a9ab088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff888109a4e3c8 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8f441668 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370
 #4: ffff8880230900e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x860
 #5: ffff8880241e8250 (&devlink->lock_key#9){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x170
 #6: ffffffff8fbccd88 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xed/0x680
 #7: ffff8881137a0d40 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x583/0x2370
 #8: ffffffff8e7646b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770
2 locks held by syz.5.552/10088:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 35 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
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+0xfd9/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 10040 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__lock_acquire+0x197b/0x2cf0
Code: 14 25 ff 0f 00 00 39 05 6f 04 82 12 73 06 89 05 67 04 82 12 48 8b 02 48 89 df 4c 39 e8 0f 84 2c fe ff ff 4c 89 60 30 48 8b 00 <4c> 39 e8 75 f4 48 89 df e9 18 fe ff ff 48 89 fb 48 c7 c7 f0 c5 62
RSP: 0018:ffffc9000733edc0 EFLAGS: 00000006
RAX: ffffffff96a88298 RBX: 0000000000000111 RCX: 0000000000000004
RDX: ffffffff96a79508 RSI: ffff8881b75c8d60 RDI: 0000000000000111
RBP: 3a7f4f3a6d939d96 R08: ffffc9000733ed88 R09: 0000000000000020
R10: ffff888173c7d858 R11: ffffffff81a1f560 R12: ffffffff96a79818
R13: ffffffff93c53338 R14: ffff8881b75c8000 R15: 0000000000000003
FS:  0000555586d37500(0000) GS:ffff88818de63000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30611ff8 CR3: 00000001b5c96000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0xf0/0x2e0
 psi_write_begin+0xab/0x160
 psi_task_change+0xd4/0x340
 enqueue_task+0x33f/0x410
 ttwu_do_activate+0x1cc/0x660
 try_to_wake_up+0x724/0x1390
 kick_pool+0x47d/0x640
 __queue_work+0xd10/0x1020
 queue_work_on+0x106/0x1d0
 inet6addr_event+0x9f/0xd0
 notifier_call_chain+0x1be/0x400
 atomic_notifier_call_chain+0xda/0x180
 addrconf_ifdown+0xeb3/0x1a40
 addrconf_notify+0x1bc/0x1050
 notifier_call_chain+0x1be/0x400
 netif_close_many+0x2ae/0x420
 unregister_netdevice_many_notify+0x81f/0x2370
 unregister_netdevice_queue+0x31f/0x360
 nsim_destroy+0x1e5/0x680
 __nsim_dev_port_del+0x14d/0x1b0
 nsim_dev_reload_destroy+0x288/0x490
 nsim_drv_remove+0x58/0x170
 device_release_driver_internal+0x46f/0x860
 bus_remove_device+0x34d/0x440
 device_del+0x527/0x8f0
 device_unregister+0x21/0xf0
 del_device_store+0x2b0/0x370
 kernfs_fop_write_iter+0x3af/0x540
 vfs_write+0x61d/0xb90
 ksys_write+0x150/0x270
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0434d5cfce
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007ffd32e4e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000555586d37500 RCX: 00007f0434d5cfce
RDX: 0000000000000001 RSI: 00007ffd32e4e1f0 RDI: 0000000000000005
RBP: 00007f0434e3351c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffd32e4e1f0 R14: 00007f0435b44620 R15: 0000000000000003
 </TASK>
