INFO: task syz.6.735:9427 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.735       state:D stack:27032 pid:9427  tgid:9426  ppid:7979   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x14ef/0x4fb0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x61e/0x920
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x290
 ksys_sync+0xa0/0x170
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fec0979acb9
RSP: 002b:00007fec0a6bf028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fec09a15fa0 RCX: 00007fec0979acb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fec09a15fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fec09a16038 R14: 00007fec09a15fa0 R15: 00007ffffaff21c8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/36:
 #0: ffffffff8e341b60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5655:
 #0: ffff8881148dc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
2 locks held by syz-executor/5833:
3 locks held by syz-executor/5838:
1 lock held by syz.6.735/9427:
 #0: ffff88816be3e0e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.1.1093/11544:
 #0: ffff8881aafaa0e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x289/0x3d0
1 lock held by syz.9.1097/11625:
 #0: ffff88816be3e0e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
2 locks held by syz.3.1215/12411:
2 locks held by syz.6.1217/12413:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 36 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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xf90/0xfe0
 kthread+0x726/0x8b0
 ret_from_fork+0x51b/0xa40
 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: 12411 Comm: syz.3.1215 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:rcu_is_watching+0x3a/0xb0
Code: e8 cb 65 cd 09 89 c3 83 f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd d0 fd c5 8d 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 6c 42 81 00 48 c7 c3 d8 86 c2 92 49 03 1e 48 89
RSP: 0018:ffffc900045e7050 EFLAGS: 00000246
RAX: 1ffffffff1b8bfbb RBX: 0000000000000001 RCX: 0000000080000001
RDX: ffffc900045e7101 RSI: ffffffff8be08f40 RDI: ffffffff8be08f00
RBP: dffffc0000000000 R08: ffffc900045e7c58 R09: 0000000000000000
R10: ffffc900045e71f8 R11: fffff520008bce41 R12: ffffc900045e7c68
R13: ffffffff8174a315 R14: ffffffff8dc5fdd8 R15: dffffc0000000000
FS:  00007f32acd796c0(0000) GS:ffff8882a9a0b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f32a2bff000 CR3: 0000000117634000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_release+0x4b/0x3a0
 unwind_next_frame+0x1aaa/0x23c0
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 save_stack+0x122/0x230
 __set_page_owner+0x8d/0x4c0
 post_alloc_hook+0x228/0x280
 get_page_from_freelist+0x24dc/0x2580
 __alloc_frozen_pages_noprof+0x18d/0x380
 alloc_pages_mpol+0x232/0x4a0
 folio_alloc_mpol_noprof+0x39/0x70
 shmem_alloc_and_add_folio+0x445/0xf80
 shmem_get_folio_gfp+0x5a9/0x1670
 shmem_write_begin+0x16c/0x330
 generic_perform_write+0x2e2/0x8f0
 shmem_file_write_iter+0xf8/0x120
 vfs_write+0x61d/0xb90
 ksys_write+0x150/0x270
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f32abf5b58e
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:00007f32acd78da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f32acd796c0 RCX: 00007f32abf5b58e
RDX: 0000000001000000 RSI: 00007f32a1c00000 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000007
R13: 00007f32acd78ee0 R14: 00007f32acd78ea0 R15: 00007f32a1c00000
 </TASK>
