INFO: task syz.5.275:7582 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.275       state:D stack:28936 pid:7582  tgid:7580  ppid:7297   task_flags:0x400040 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
 __iterate_supers+0x126/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f466a18ebe9
RSP: 002b:00007f466b0a2038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f466a3b6090 RCX: 00007f466a18ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f466a3b6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f466a3b6128 R14: 00007f466a3b6090 R15: 00007fffaaaf0148
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by kworker/u10:3/64:
 #0: ffff88801cf5c148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000172fbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
2 locks held by getty/5676:
 #0: ffff8880288cf0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029032f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
1 lock held by syz.5.275/7582:
 #0: ffff8881096ba0e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
3 locks held by syz-executor/8006:
6 locks held by kworker/u8:5/9344:
 #0: ffff88801b2f7148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000291fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f52b9f0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800
 #3: ffffffff8f538888 (rtnl_mutex){+.+.}-{4:4}, at: wg_netns_pre_exit+0x1c/0x1d0
 #4: ffff88803d7354e8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_netns_pre_exit+0xb0/0x1d0
 #5: ffffffff8e13f978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730
1 lock held by syz.5.897/11020:
 #0: ffff8881096ba0e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.9.958/11295:
 #0: ffff8881096ba0e0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
3 locks held by syz.8.1111/11991:
2 locks held by syz.7.1109/12001:

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

NMI backtrace for cpu 1
CPU: 1 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 793 Comm: kworker/0:2 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
Workqueue: events drain_vmap_area_work
RIP: 0010:rcu_is_watching+0x5a/0xb0
Code: f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 3c bc 7c 00 48 c7 c3 98 7f a1 92 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 <84> c0 75 34 8b 03 65 ff 0d 99 f2 f9 10 74 11 83 e0 04 c1 e8 02 5b
RSP: 0018:ffffc90004aff618 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: ffff88804b032f98 RCX: 9eccc9d2d1256400
RDX: ffff888020d50000 RSI: ffffffff8be33660 RDI: ffffffff8be33620
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff822e3662
R10: dffffc0000000000 R11: fffff9400013c827 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8dbdfd10 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555588fe85c8 CR3: 000000010ef80000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 page_ext_put+0x2f/0xc0
 __reset_page_owner+0x67/0x1f0
 __free_frozen_pages+0xbc4/0xd30
 kasan_depopulate_vmalloc_pte+0x74/0xa0
 __apply_to_page_range+0xb92/0x1380
 kasan_release_vmalloc+0xa2/0xd0
 purge_vmap_node+0x214/0x8f0
 __purge_vmap_area_lazy+0x7a4/0xb40
 drain_vmap_area_work+0x27/0x40
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
