INFO: task syz.7.702:12004 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.702       state:D stack:28744 pid:12004 tgid:11925 ppid:11752  task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_write_slowpath+0x872/0xfe0
 down_write_nested+0x1b5/0x200
 filename_create+0x1f8/0x3c0
 do_symlinkat+0xbc/0x3f0
 __x64_sys_symlink+0x7a/0x90
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f14fed8ec29
RSP: 002b:00007f14ffbcf038 EFLAGS: 00000246 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007f14fefd6090 RCX: 00007f14fed8ec29
RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 00002000000008c0
RBP: 00007f14fee11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f14fefd6128 R14: 00007f14fefd6090 R15: 00007ffe4226d898
 </TASK>
INFO: task syz.7.702:12005 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.702       state:D stack:26008 pid:12005 tgid:11925 ppid:11752  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
 lookup_slow+0x46/0x70
 walk_component+0x2d2/0x400
 path_lookupat+0x163/0x430
 filename_lookup+0x212/0x570
 user_path_at+0x3a/0x60
 __se_sys_chdir+0x91/0x280
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f14fed8ec29
RSP: 002b:00007f14ffbae038 EFLAGS: 00000246 ORIG_RAX: 0000000000000050
RAX: ffffffffffffffda RBX: 00007f14fefd6180 RCX: 00007f14fed8ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000140
RBP: 00007f14fee11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f14fefd6218 R14: 00007f14fefd6180 R15: 00007ffe4226d898
 </TASK>
INFO: task syz.7.702:12044 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.702       state:D stack:28936 pid:12044 tgid:11925 ppid:11752  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
 path_openat+0x8cb/0x3830
 do_filp_open+0x1fa/0x410
 do_sys_openat2+0x121/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f14fed8ec29
RSP: 002b:00007f14ffb8d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f14fefd6270 RCX: 00007f14fed8ec29
RDX: 0000000000088000 RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007f14fee11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000189 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f14fefd6308 R14: 00007f14fefd6270 R15: 00007ffe4226d898
 </TASK>
INFO: task syz.7.702:12046 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.702       state:D stack:28936 pid:12046 tgid:11925 ppid:11752  task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_write_slowpath+0x872/0xfe0
 down_write_nested+0x1b5/0x200
 filename_create+0x1f8/0x3c0
 do_mkdirat+0xa0/0x590
 __x64_sys_mkdirat+0x87/0xa0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f14fed8ec29
RSP: 002b:00007f14ffb6c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f14fefd6360 RCX: 00007f14fed8ec29
RDX: 0000000000000000 RSI: 0000200000002040 RDI: ffffffffffffff9c
RBP: 00007f14fee11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f14fefd63f8 R14: 00007f14fefd6360 R15: 00007ffe4226d898
 </TASK>
INFO: task syz.7.702:12049 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.702       state:D stack:26632 pid:12049 tgid:11925 ppid:11752  task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_write_slowpath+0x872/0xfe0
 down_write+0x1ab/0x1f0
 path_openat+0x8da/0x3830
 do_filp_open+0x1fa/0x410
 do_sys_openat2+0x121/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f14fed8ec29
RSP: 002b:00007f14ffb4b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f14fefd6450 RCX: 00007f14fed8ec29
RDX: 000000000000275a RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007f14fee11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f14fefd64e8 R14: 00007f14fefd6450 R15: 00007ffe4226d898
 </TASK>
INFO: task syz.7.702:12057 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.702       state:D stack:28936 pid:12057 tgid:11925 ppid:11752  task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_write_slowpath+0x872/0xfe0
 down_write_nested+0x1b5/0x200
 filename_create+0x1f8/0x3c0
 do_mkdirat+0xa0/0x590
 __x64_sys_mkdirat+0x87/0xa0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f14fed8d497
RSP: 002b:00007f14fbfede68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f14fbfedef0 RCX: 00007f14fed8d497
RDX: 00000000000001ff RSI: 00002000000000c0 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000000c0
R13: 00007f14fbfedeb0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
INFO: task syz.7.702:12058 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.702       state:D stack:28936 pid:12058 tgid:11925 ppid:11752  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
 lookup_slow+0x46/0x70
 walk_component+0x2d2/0x400
 path_lookupat+0x163/0x430
 filename_lookup+0x212/0x570
 user_path_at+0x3a/0x60
 __se_sys_mount+0x2d3/0x410
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f14fed8ec29
RSP: 002b:00007f14fbbcb038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f14fefd6630 RCX: 00007f14fed8ec29
RDX: 0000200000000b80 RSI: 0000200000000000 RDI: 0000000000000000
RBP: 00007f14fee11e41 R08: 0000200000001640 R09: 0000000000000000
R10: 0000000000018000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f14fefd66c8 R14: 00007f14fefd6630 R15: 00007ffe4226d898
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
3 locks held by kworker/u10:2/40:
 #0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900006efbc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f53a1c8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60
2 locks held by dhcpcd/5595:
 #0: ffff8880318e06d8 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xbd/0xe90
 #1: ffffffff8f53a1c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200
2 locks held by getty/5677:
 #0: ffff88810e5470a0 (&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
4 locks held by syz.7.702/11926:
 #0: ffff88802e7ec428 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90
 #1: ffff888029ec9810 (&sb->s_type->i_mutex_key#22/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0
 #2: ffff888134604398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220
 #3: ffff888134626710 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x542/0x1de0
2 locks held by syz.7.702/12004:
 #0: ffff88802e7ec428 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90
 #1: ffff888029ec9810 (&sb->s_type->i_mutex_key#22/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0
1 lock held by syz.7.702/12005:
 #0: ffff888029ec9810 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: lookup_slow+0x46/0x70
1 lock held by syz.7.702/12044:
 #0: ffff888029ec9810 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: path_openat+0x8cb/0x3830
2 locks held by syz.7.702/12046:
 #0: ffff88802e7ec428 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90
 #1: ffff888029ec9810 (&sb->s_type->i_mutex_key#22/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0
2 locks held by syz.7.702/12049:
 #0: ffff88802e7ec428 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90
 #1: ffff888029ec9810 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: path_openat+0x8da/0x3830
2 locks held by syz.7.702/12057:
 #0: ffff88802e7ec428 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90
 #1: ffff888029ec9810 (&sb->s_type->i_mutex_key#22/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0
1 lock held by syz.7.702/12058:
 #0: ffff888029ec9810 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: lookup_slow+0x46/0x70
6 locks held by kworker/u8:5/13286:
 #0: ffff88801b2f7148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000444fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffffffff8f52d310 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800
 #3: ffffffff8f53a1c8 (rtnl_mutex){+.+.}-{4:4}, at: caif_exit_net+0x6a/0x4a0
 #4: ffff888036214980 (&caifn->caifdevs.lock){+.+.}-{4:4}, at: caif_exit_net+0x7d/0x4a0
 #5: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730
2 locks held by syz-executor/13667:
3 locks held by syz-executor/13735:
1 lock held by syz-executor/14381:
 #0: ffffffff8f53a1c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0
1 lock held by syz.7.1014/15138:
 #0: ffff88803ab280e0 (&type->s_umount_key#66){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.7.1014/15139:
 #0: ffff88803ab280e0 (&type->s_umount_key#66){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
7 locks held by syz-executor/15150:
 #0: ffff888106c46428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xb30
 #1: ffff8881136eb888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540
 #2: ffff888022cc4b48 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540
 #3: ffffffff8edb0408 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360
 #4: ffff88810e62d0e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800
 #5: ffff88810e62e250 (&devlink->lock_key#23){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160
 #6: ffffffff8e13fa40 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570

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

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+0x439/0x7d0
 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: 13667 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:down_write+0xd6/0x1f0
Code: 00 48 89 df be 08 00 00 00 e8 b6 01 a7 f6 4c 89 f7 be 08 00 00 00 e8 a9 01 a7 f6 48 8b 44 24 20 b9 01 00 00 00 f0 48 0f b1 0b <0f> 85 c2 00 00 00 48 c7 c0 60 d8 a3 8f 48 c1 e8 03 42 0f b6 04 38
RSP: 0018:ffffc90004caf8c0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88811b5f8340 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffc90004caf8e0
RBP: ffffc90004caf950 R08: ffffc90004caf8e7 R09: 1ffff92000995f1c
R10: dffffc0000000000 R11: fffff52000995f1d R12: 1ffff92000995f18
R13: ffff88811b5f9250 R14: ffffc90004caf8e0 R15: dffffc0000000000
FS:  000055557e90b500(0000) GS:ffff8881a3c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffcca40b08 CR3: 000000003155c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 f2fs_write_checkpoint+0x51c/0x1df0
 kill_f2fs_super+0x2c3/0x6c0
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe74ad8ff57
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffc3d33ad28 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fe74ae11c2d RCX: 00007fe74ad8ff57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc3d33ade0
RBP: 00007ffc3d33ade0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc3d33be70
R13: 00007fe74ae11c2d R14: 000000000005fafe R15: 00007ffc3d33beb0
 </TASK>
