INFO: task syz.2.591:10566 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.591       state:D stack:24616 pid:10566 tgid:10565 ppid:10242  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
 __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: 0033:0x7fc90238ebe9
RSP: 002b:00007fc903265038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fc9025c5fa0 RCX: 00007fc90238ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fc9025c5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc9025c6038 R14: 00007fc9025c5fa0 R15: 00007fffcca19dd8
 </TASK>
INFO: task syz.2.591:10568 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.591       state:D stack:22072 pid:10568 tgid:10565 ppid:10242  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
 __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: 0033:0x7fc90238ebe9
RSP: 002b:00007fc903244038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fc9025c6090 RCX: 00007fc90238ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fc9025c6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc9025c6128 R14: 00007fc9025c6090 R15: 00007fffcca19dd8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
4 locks held by kworker/u10:2/40:
 #0: ffff8880118e6948 ((wq_completion)btree_update){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900006efbc0 ((work_completion)(&c->btree_interior_update_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff88803d404398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220
 #3: ffff88803d426710 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x542/0x1de0
4 locks held by kworker/u9:6/1091:
 #0: ffff888136639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140
 #1: ffff888136624008 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880
 #2: ffff888136625918 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x8ee/0xf30
 #3: ffffffff99d3f1b8 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xbb/0x420
2 locks held by getty/5674:
 #0: ffff888110cfc0a0 (&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
4 locks held by syz-executor/5846:
1 lock held by syz.2.591/10566:
 #0: ffff888110b5c0e0 (&type->s_umount_key#61){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.2.591/10568:
 #0: ffff888110b5c0e0 (&type->s_umount_key#61){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.0.651/10910:
 #0: ffff888110b5c0e0 (&type->s_umount_key#61){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
2 locks held by syz-executor/12096:
 #0: ffff8881265da0e0 (&type->s_umount_key#67){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffff88803d400278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xf8/0x900
4 locks held by syz-executor/12787:

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

NMI backtrace for cpu 0
CPU: 0 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+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: 6585 Comm: kworker/u8:4 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: bat_events batadv_nc_worker
RIP: 0010:mark_lock+0xd/0x190
Code: 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 8b 46 20 <89> c1 81 e1 00 00 03 00 83 f9 01 bb 09 00 00 00 83 db 00 83 fa 08
RSP: 0018:ffffc9000315f808 EFLAGS: 00000046
RAX: 0000000000040789 RBX: ffff888108909cc0 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffff88810890a800 RDI: ffff888108909cc0
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8b47c057
R10: dffffc0000000000 R11: fffffbfff1f47207 R12: 00000000ffffff05
R13: 0000000000000003 R14: ffff88810890a800 R15: ffff88810890a820
FS:  0000000000000000(0000) GS:ffff8881a3c18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c369c6c CR3: 000000010fc0c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __lock_acquire+0x9b6/0xd20
 lock_acquire+0x120/0x360
 _raw_spin_lock_bh+0x36/0x50
 batadv_nc_purge_paths+0xe7/0x3b0
 batadv_nc_worker+0x369/0x610
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
