INFO: task syz.3.1285:11357 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1285      state:D stack:17192 pid:11357 tgid:11356 ppid:7718   task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 __closure_sync+0x163/0x220
 bch2_read_iter+0x1034/0x1440
 vfs_read+0x55a/0xa30
 ksys_read+0x145/0x250
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1cf518ebe9
RSP: 002b:00007f1cf6055038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f1cf53c5fa0 RCX: 00007f1cf518ebe9
RDX: 0000000000001000 RSI: 0000200000001400 RDI: 0000000000000004
RBP: 00007f1cf5211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1cf53c6038 R14: 00007f1cf53c5fa0 R15: 00007ffc623f71b8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e33cda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by kworker/u10:1/36:
2 locks held by kworker/u10:2/40:
2 locks held by getty/5671:
 #0: ffff8880266e50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000291b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
1 lock held by syz.3.1285/11357:
 #0: ffff888027efb4f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320
2 locks held by syz.6.1947/14350:
2 locks held by syz.7.1950/14389:
2 locks held by dhcpcd/14390:
 #0: ffff88802a9aee08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240
 #1: ffffffff8e342838 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730

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

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+0xf60/0xfa0
 kthread+0x711/0x8a0
 ret_from_fork+0x47f/0x820
 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: 14389 Comm: syz.7.1950 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:check_preemption_disabled+0x59/0x120
Code: 8b 0d ab a4 43 07 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d e9 51 c9 02 00 cc 48 c7 04 24 00 00 00 00 9c <8f> 04 24 f7 04 24 00 02 00 00 74 c8 65 4c 8b 3c 25 08 60 c2 92 41
RSP: 0018:ffffc90002ed76f8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 00000000ffffffff RCX: 0000000080000000
RDX: 0000000000000000 RSI: ffffffff8dbd1609 RDI: ffffffff8c037100
RBP: 00000000ffffffff R08: 0000000000000000 R09: ffffffff822c5de8
R10: dffffc0000000000 R11: fffff9400034bad1 R12: 0000000000000246
R13: ffff88810cdd0000 R14: ffffffff8e33ce60 R15: dffffc0000000000
FS:  00007f356ecac6c0(0000) GS:ffff8881a39fa000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555d1bc7b600 CR3: 000000012042a000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_is_held_type+0x79/0x190
 rcu_read_lock_sched_held+0x89/0x100
 mem_cgroup_from_task+0x4d/0x120
 get_mem_cgroup_from_mm+0xd6/0x2a0
 __mem_cgroup_charge+0x15/0x80
 shmem_alloc_and_add_folio+0x7c1/0xf60
 shmem_get_folio_gfp+0x59d/0x1660
 shmem_write_begin+0xf7/0x2b0
 generic_perform_write+0x2c5/0x900
 shmem_file_write_iter+0xf8/0x120
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f356dd8d69f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007f356ecabdf0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f356dd8d69f
RDX: 0000000001000000 RSI: 00007f3563a00000 RDI: 0000000000000006
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000009687
R10: 0000200000009682 R11: 0000000000000293 R12: 0000000000000006
R13: 00007f356ecabef0 R14: 00007f356ecabeb0 R15: 00007f3563a00000
 </TASK>
