INFO: task syz.2.4802:26693 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.4802      state:D stack:25464 pid:26693 tgid:26692 ppid:10844  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7f7/0x1550
 sync_bdevs+0x27e/0x470
 __ia32_sys_sync+0xc5/0x120
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9bb499cdd9
RSP: 002b:00007f9bb5932028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f9bb4c15fa0 RCX: 00007f9bb499cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f9bb4c15fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9bb4c16038 R14: 00007f9bb4c15fa0 R15: 00007ffc98637738
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e95cda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5437:
 #0: ffff8881744d90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000346e2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
1 lock held by udevd/14773:
 #0: ffff88816a667350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by kworker/0:6/15150:
 #0: ffff88812103b020 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150
4 locks held by kworker/u8:2/17141:
1 lock held by syz.2.4802/26693:
 #0: ffff88816a667350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470
1 lock held by syz.6.5032/27761:
 #0: ffff88816a667350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470
2 locks held by syz.0.5193/28700:
 #0: ffff8881190820d8 (&type->s_umount_key#82/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xab0
 #1: ffff88816a667350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
2 locks held by syz.5.5457/29972:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 35 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd3/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 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: 29972 Comm: syz.5.5457 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:rcu_is_watching+0x3a/0xb0
Code: e8 eb 78 fd 09 89 c3 83 f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 90 87 26 8e 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 cc 37 86 00 48 c7 c3 d8 39 3a 93 49 03 1e 48 89
RSP: 0018:ffffc900049e7428 EFLAGS: 00000246
RAX: 1ffffffff1c4d0f2 RBX: 0000000000000000 RCX: 0000000080000001
RDX: 000000005a44979c RSI: ffffffff8c28b4c0 RDI: ffffffff8c28b480
RBP: ffffc900049e7570 R08: ffffffff823a33b9 R09: ffffffff8e95cda0
R10: dffffc0000000000 R11: fffff9400013e019 R12: 0000000000000017
R13: dffffc0000000000 R14: ffffffff8e268790 R15: dffffc0000000000
FS:  00007f2c0765e6c0(0000) GS:ffff88818dc90000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2bfd3ff000 CR3: 0000000111e4c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 percpu_ref_put+0xb5/0x180
 __mem_cgroup_uncharge_folios+0xfd/0x1d0
 folios_put_refs+0xa35/0xb80
 shmem_undo_range+0x52c/0x1660
 shmem_evict_inode+0x289/0xae0
 evict+0x61e/0xb10
 __dentry_kill+0x1a2/0x690
 finish_dput+0xc9/0x480
 __fput+0x691/0xa60
 fput_close_sync+0x11f/0x240
 __x64_sys_close+0x7e/0x110
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2c0675d60e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007f2c0765dda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00007f2c0765e6c0 RCX: 00007f2c0675d60e
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f2c0765dee0 R14: 00007f2c0765dea0 R15: 00007f2bfc400000
 </TASK>
