INFO: task syz-executor.1:22451 blocked for more than 143 seconds.
      Not tainted 5.15.148-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:24792 pid:22451 ppid: 21695 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
 rwsem_down_read_slowpath+0x605/0xb40 kernel/locking/rwsem.c:1047
 __down_read_common kernel/locking/rwsem.c:1231 [inline]
 __down_read kernel/locking/rwsem.c:1244 [inline]
 down_read+0x9a/0x2e0 kernel/locking/rwsem.c:1490
 iterate_supers+0xac/0x1e0 fs/super.c:703
 ksys_sync+0xb9/0x1c0 fs/sync.c:102
 __do_sys_sync+0xa/0x10 fs/sync.c:113
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f20c1795da9
RSP: 002b:00007f20bfcd50c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f20c18c5120 RCX: 00007f20c1795da9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f20c17e247a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f20c18c5120 R15: 00007ffcf2d65448
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c91f220 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by klogd/2953:
2 locks held by getty/3258:
 #0: ffff88814aff3098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002bab2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
1 lock held by syz-fuzzer/3498:
4 locks held by kworker/u4:6/3638:
 #0: ffff888011dcd138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc900030b7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffffffff8d9ced10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:558
 #3: ffffffff8c9237e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #3: ffffffff8c9237e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845
3 locks held by kworker/1:14/7446:
1 lock held by syz-executor.1/20587:
 #0: ffff8880a24ca0e0 (&type->s_umount_key#105/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229
1 lock held by syz-executor.1/21244:
 #0: ffff8880963b60e0 (&type->s_umount_key#105/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229
1 lock held by syz-executor.1/22451:
 #0: ffff8880a24ca0e0 (&type->s_umount_key#106){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:703
1 lock held by syz-executor.1/23206:
 #0: ffff8880a24ca0e0 (&type->s_umount_key#106){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:703
1 lock held by syz-executor.1/24149:
 #0: ffff8880a24ca0e0 (&type->s_umount_key#106){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:703
2 locks held by kworker/u4:15/24901:

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.148-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 14 Comm: ksoftirqd/0 Not tainted 5.15.148-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
RIP: 0010:__lock_acquire+0x83/0x1ff0 kernel/locking/lockdep.c:4882
Code: 83 3d a0 5b 1c 0b 00 74 2d 48 89 f8 48 c1 e8 03 80 3c 10 00 74 14 e8 dc 5c 67 00 48 8b 7c 24 08 48 ba 00 00 00 00 00 fc ff df <48> c7 c0 c0 ff a8 8f 48 39 07 75 03 45 31 ff 89 5c 24 60 83 fd 01
RSP: 0018:ffffc90000d37960 EFLAGS: 00000046
RAX: 1ffff11027fc449d RBX: 0000000000000000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff88813fe224e8
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
R13: ffff88813fe21dc0 R14: 0000000000000000 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f47fb96e368 CR3: 0000000097318000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 do_write_seqcount_begin_nested include/linux/seqlock.h:519 [inline]
 do_write_seqcount_begin include/linux/seqlock.h:545 [inline]
 vtime_task_switch_generic+0x274/0x580 kernel/sched/cputime.c:779
 vtime_task_switch include/linux/vtime.h:95 [inline]
 finish_task_switch+0x3ea/0x630 kernel/sched/core.c:4898
 context_switch kernel/sched/core.c:5033 [inline]
 __schedule+0x12cc/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 smpboot_thread_fn+0x599/0x9d0 kernel/smpboot.c:160
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>