INFO: task syz.2.751:13582 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.751       state:D stack:25128 pid:13582 tgid:13581 ppid:13034  task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 user_get_super+0xc8/0x120
 __se_sys_quotactl+0x4da/0x950
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f196958eba9
RSP: 002b:00007f196a4d4038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f19697d5fa0 RCX: 00007f196958eba9
RDX: 0000000000000000 RSI: 0000200000000040 RDI: ffffffff80000901
RBP: 00007f1969611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f19697d6038 R14: 00007f19697d5fa0 R15: 00007fff2a7ec598
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by dhcpcd/5595:
 #0: ffff888107efe6d8 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0
 #1: ffffffff8f539b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200
2 locks held by getty/5677:
 #0: ffff888021a6f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
3 locks held by syz-executor/9459:
1 lock held by udevd/12244:
4 locks held by kworker/u8:3/13117:
 #0: ffff88801b2f7148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90002f2fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f52cc50 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800
 #3: ffff88803343d4e8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_destruct+0x116/0x2f0
1 lock held by syz.2.751/13582:
 #0: ffff888033abe0e0 (&type->s_umount_key#64){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
2 locks held by syz-executor/13585:
2 locks held by syz-executor/15827:
 #0: ffffffff8eca9140 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250
 #1: ffffffff8f539b08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70
6 locks held by syz.0.1026/15994:
2 locks held by syz.7.1027/15996:
1 lock held by udevadm/16000:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 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: 16000 Comm: udevadm 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:stack_depot_save_flags+0x163/0x860
Code: c8 31 c5 c1 c0 18 29 c5 48 8b 05 38 7e df 14 8b 0d 2a 7e df 14 21 e9 48 c1 e1 04 4c 8d 24 08 65 ff 05 41 96 a1 0d 4c 8b 3c 08 <4d> 39 e7 44 89 2c 24 74 05 45 89 d5 eb 34 45 31 ff e9 85 00 00 00
RSP: 0018:ffffc90002f6f5e8 EFLAGS: 00000282
RAX: ffff888135400000 RBX: 0000000000000000 RCX: 00000000007944a0
RDX: 00000000e05dc03f RSI: 0000000000000000 RDI: 0000000071e8ff95
RBP: 00000000ca67944a R08: 000000001a1f1096 R09: 000000000505d886
R10: 000000000000000d R11: ffffffff81ac3ae0 R12: ffff888135b944a0
R13: 0000000000000000 R14: ffffc90002f6f650 R15: ffff8880213055c0
FS:  00007f05332bfc80(0000) GS:ffff8881a3c15000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0533376440 CR3: 000000004af80000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 kasan_save_stack+0x4d/0x60
 kasan_record_aux_stack+0xbd/0xd0
 call_rcu+0x157/0x9c0
 kmem_cache_free+0x309/0x400
 exit_mmap+0x53f/0xb50
 __mmput+0x118/0x430
 exit_mm+0x1da/0x2c0
 do_exit+0x648/0x2300
 do_group_exit+0x21c/0x2d0
 __x64_sys_exit_group+0x3f/0x40
 x64_sys_call+0x21f7/0x2200
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0532efca90
Code: Unable to access opcode bytes at 0x7f0532efca66.
RSP: 002b:00007ffe161479d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f0532fed860 RCX: 00007f0532efca90
RDX: 00000000000000e7 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00007f0532fed860 R08: 00007ffe16147810 R09: 00007ffe16147910
R10: 00007ffe16147870 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0532ff1658 R15: 0000000000000001
 </TASK>
