INFO: task syz.3.877:13524 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.877       state:D stack:24696 pid:13524 tgid:13522 ppid:12831  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x6d9/0x940
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 user_get_super+0xc8/0x120
 __se_sys_quotactl+0x540/0x9e0
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f68f0b9cdd9
RSP: 002b:00007f68eedee028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f68f0e15fa0 RCX: 00007f68f0b9cdd9
RDX: 0000000000000000 RSI: 0000200000000140 RDI: ffffffff80000600
RBP: 00007f68f0c32d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000340 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f68f0e16038 R14: 00007f68f0e15fa0 R15: 00007ffe0c08d6d8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
3 locks held by kworker/u10:1/37:
 #0: ffff8881000ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc90000ad7c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffffffff8fdce940 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
1 lock held by dhcpcd/5357:
 #0: ffffffff8fdce940 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_deladdr+0x23d/0x370
2 locks held by getty/5441:
 #0: ffff88817364b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000346b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
4 locks held by kworker/1:7/6341:
 #0: ffff88823c63aea0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150
 #1: ffff88823c624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880
 #2: ffffc900043e7870 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_atomic_helper_dirtyfb+0x106/0xf80
 #3: ffffc900043e7898 (crtc_ww_class_mutex){+.+.}-{4:4}, at: drm_atomic_helper_dirtyfb+0x106/0xf80
2 locks held by syz-executor/9265:
1 lock held by syz.3.877/13524:
 #0: ffff88810bc000d8 (&type->s_umount_key#51){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz-executor/13548:
 #0: ffffffff8e963068 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770
1 lock held by syz.0.1202/16238:
 #0: ffff88810bc000d8 (&type->s_umount_key#51){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
7 locks held by syz-executor/16613:
2 locks held by syz.2.1235/16675:

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

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+0xfd3/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 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: 16613 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:__list_del_entry_valid_or_report+0x88/0x190
Code: 00 01 00 00 00 00 ad de 4d 39 e6 0f 84 84 00 00 00 49 83 c4 22 4d 39 e7 0f 84 94 00 00 00 4d 89 fc 49 c1 ec 03 43 80 3c 2c 00 <74> 08 4c 89 ff e8 5e 92 74 fd 49 39 1f 0f 85 92 00 00 00 4d 8d 7e
RSP: 0018:ffffc900066f7438 EFLAGS: 00000246
RAX: 1ffff110219788e4 RBX: ffff88810cbc4720 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff88810cbc4728
RBP: 1ffff110219788e7 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000cdee7c R12: 1ffff110218c58e4
R13: dffffc0000000000 R14: ffff888104b79008 R15: ffff88810c62c720
FS:  0000555558bdc500(0000) GS:ffff88818dc93000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556035da28 CR3: 00000001a4182000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __kobject_del+0x136/0x330
 kobject_del+0x45/0x60
 device_del+0x775/0x8f0
 unregister_netdevice_many_notify+0x1d5f/0x22c0
 unregister_netdevice_queue+0x31f/0x360
 nsim_destroy+0x24e/0x830
 __nsim_dev_port_del+0x14f/0x200
 nsim_dev_reload_destroy+0x288/0x490
 nsim_drv_remove+0x58/0x170
 device_release_driver_internal+0x46f/0x870
 bus_remove_device+0x455/0x570
 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+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8cf215d60e
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:00007ffd0a4dcf08 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000555558bdc500 RCX: 00007f8cf215d60e
RDX: 0000000000000001 RSI: 00007ffd0a4dcf90 RDI: 0000000000000005
RBP: 00007f8cf22335ec R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffd0a4dcf90 R14: 00007f8cf2f44620 R15: 0000000000000003
 </TASK>
