INFO: task syz.8.4895:26512 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.8.4895      state:D stack:25328 pid:26512 tgid:26511 ppid:26115  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17d9/0x56c0
 schedule+0x164/0x2b0
 cgroup_lock_and_drain_offline+0x51a/0x650
 cgroup_kn_lock_live+0x120/0x230
 cgroup_subtree_control_write+0x4b5/0x1080
 cgroup_file_write+0x331/0x8f0
 kernfs_fop_write_iter+0x3a4/0x540
 vfs_write+0x612/0xba0
 ksys_write+0x150/0x270
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa13699de99
RSP: 002b:00007fa137903028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fa136c25fa0 RCX: 00007fa13699de99
RDX: 000000000000000b RSI: 0000200000000180 RDI: 0000000000000008
RBP: 00007fa136a33eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa136c26038 R14: 00007fa136c25fa0 R15: 00007ffe5967f5d8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5438:
 #0: ffff88816f3e70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360
3 locks held by syz.8.4895/26512:
 #0: ffff888111ed5af0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320
 #1: ffff88810d312450 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0
 #2: ffff888111312880 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d8/0x540
1 lock held by syz-executor/29716:
2 locks held by syz.2.5631/30341:
 #0: ffff8881145d20d8 (&type->s_umount_key#55/1){+.+.}-{4:4}, at: sget_fc+0x938/0x1900
 #1: ffff8881145d2640 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc+0xcf/0x990
1 lock held by syz.0.5633/30356:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 34 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/0x380
 sys_info+0x135/0x170
 watchdog+0xfd7/0x1030
 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: 30356 Comm: syz.0.5633 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:do_raw_spin_unlock+0x2b/0x210
Code: 1f 40 d6 55 41 57 41 56 41 55 41 54 53 48 89 fb 49 bc 00 00 00 00 00 fc ff df 4c 8d 77 04 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 <84> c0 0f 85 57 01 00 00 41 81 3e ad 4e ad de 0f 85 c6 00 00 00 48
RSP: 0018:ffffc90005a676d8 EFLAGS: 00000803
RAX: 0000000000000000 RBX: ffff888114061580 RCX: 0000000080000001
RDX: 0000000000000002 RSI: ffffffff8e4b1855 RDI: ffff888114061580
RBP: ffffc90005a67870 R08: ffffffff90578737 R09: 1ffffffff20af0e6
R10: dffffc0000000000 R11: fffffbfff20af0e7 R12: dffffc0000000000
R13: ffffc90005a677c0 R14: ffff888114061584 R15: 0000000000000001
FS:  00007f01594c66c0(0000) GS:ffff88818d951000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f014f1ff000 CR3: 0000000172e78000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 _raw_spin_unlock_irq+0x1e/0x50
 shmem_add_to_page_cache+0xa5e/0xd40
 shmem_alloc_and_add_folio+0x854/0xf60
 shmem_get_folio_gfp+0x5da/0x16d0
 shmem_write_begin+0x16c/0x330
 generic_perform_write+0x2d5/0x8f0
 shmem_file_write_iter+0xf8/0x120
 vfs_write+0x612/0xba0
 ksys_write+0x150/0x270
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f015855e6ce
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:00007f01594c5da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f01594c66c0 RCX: 00007f015855e6ce
RDX: 0000000001000000 RSI: 00007f014e200000 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
R13: 00007f01594c5ee0 R14: 00007f01594c5ea0 R15: 00007f014e200000
 </TASK>
