INFO: task syz.3.1438:9723 blocked for more than 143 seconds.
      Not tainted 6.16.0-syzkaller-08685-g260f6f4fda93-dirty #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1438      state:D stack:25928 pid:9723  tgid:9722  ppid:6766   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e3/0x1340
 sync_bdevs+0x1ac/0x340
 ksys_sync+0xb9/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7febfc78eb69
RSP: 002b:00007febfd5b6038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007febfc9b5fa0 RCX: 00007febfc78eb69
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007febfc9b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007febfc9b5fa0 R15: 00007ffdf0bf0d38
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e139de0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5650:
 #0: ffff8880216930a0 (&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
1 lock held by udevd/5915:
 #0: ffff888020c6b358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.3.1438/9723:
 #0: ffff888020c6b358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
1 lock held by syz.0.2194/11779:
 #0: ffff888020c6b358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ac/0x340
2 locks held by syz.4.3158/14264:
4 locks held by syz.7.3162/14263:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 35 Comm: khungtaskd Not tainted 6.16.0-syzkaller-08685-g260f6f4fda93-dirty #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: 18 Comm: rcu_exp_gp_kthr Not tainted 6.16.0-syzkaller-08685-g260f6f4fda93-dirty #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:do_raw_spin_lock+0x12e/0x290
Code: 00 48 89 df be 04 00 00 00 e8 6e b4 84 00 48 8d 7c 24 40 be 04 00 00 00 e8 5f b4 84 00 8b 44 24 40 b9 01 00 00 00 f0 0f b1 0b <0f> 85 dd 00 00 00 65 8b 1d 49 87 fc 10 48 b9 00 00 00 00 00 fc ff
RSP: 0018:ffffc900001579a0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff8e13f100 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc900001579e0
RBP: ffffc90000157a50 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200002af3c R12: ffffffff8e13f110
R13: ffffffff8e13f108 R14: 1ffffffff1c27e22 R15: 1ffffffff1c27e21
FS:  0000000000000000(0000) GS:ffff8880b8679000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31e1fffc CR3: 00000000217a2000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 _raw_spin_lock_irqsave+0xb3/0xf0
 sync_rcu_exp_select_node_cpus+0x30/0xbb0
 rcu_exp_sel_wait_wake+0x2bb/0xe20
 kthread_worker_fn+0x507/0xb60
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
