INFO: task syz.0.708:20262 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.708       state:D stack:24664 pid:20262 tgid:20261 ppid:17750  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x6d9/0x940
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x250
 __ia32_sys_sync+0xa0/0x120
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7626b9cdd9
RSP: 002b:00007f7627b38028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f7626e15fa0 RCX: 00007f7626b9cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f7626e15fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7626e16038 R14: 00007f7626e15fa0 R15: 00007ffe20dc3088
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5437:
 #0: ffff88810f9800a0 (&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
2 locks held by syz-executor/10471:
1 lock held by syz.0.708/20262:
 #0: ffff8881b3ef40d8 (&type->s_umount_key#64){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.5.763/21660:
 #0: ffff8881b3ef40d8 (&type->s_umount_key#64){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
2 locks held by syz.0.1084/28488:
2 locks held by syz.8.1085/28493:

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

NMI backtrace for cpu 1
CPU: 1 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+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: 28488 Comm: syz.0.1084 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:__lock_acquire+0x19/0x2cf0
Code: cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 48 81 ec e8 00 00 00 65 48 8b 05 57 4d 97 11 <48> 89 84 24 e0 00 00 00 65 48 8b 05 2f 4d 97 11 48 89 44 24 08 31
RSP: 0018:ffffc900079beef0 EFLAGS: 00000086
RAX: 04dccc14466b4400 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e95cd60
RBP: ffffffff8176f256 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc900079bf1f8 R11: ffffffff81b0e910 R12: 0000000000000002
R13: ffffffff8e95cd60 R14: 0000000000000000 R15: 0000000000000246
FS:  00007fd3eb4106c0(0000) GS:ffff88818dc90000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd3e11ff000 CR3: 0000000020d2e000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0x106/0x350
 unwind_next_frame+0xc3/0x2550
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 save_stack+0x122/0x230
 __set_page_owner+0x8d/0x4c0
 post_alloc_hook+0x231/0x280
 get_page_from_freelist+0x24ba/0x2540
 __alloc_frozen_pages_noprof+0x18d/0x380
 alloc_pages_mpol+0x235/0x490
 folio_alloc_mpol_noprof+0x39/0x160
 shmem_alloc_and_add_folio+0x442/0xf80
 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+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd3ea55d60e
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:00007fd3eb40fda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fd3eb4106c0 RCX: 00007fd3ea55d60e
RDX: 0000000001000000 RSI: 00007fd3e0200000 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 00007fd3eb40fee0 R14: 00007fd3eb40fea0 R15: 00007fd3e0200000
 </TASK>
