[syzbot] [kernel?] WARNING in notifier_call_chain (2)

[syzbot <syzbot+c81bea693d8cd125f5f2@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    231825b2e1ff Revert "unicode: Don't special case ignorable..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1019ebe8580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b874549ac3d0b012
dashboard link: https://syzkaller.appspot.com/bug?extid=c81bea693d8cd125f5f2
compiler:       gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/09aec3e43efa/disk-231825b2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/41d874d46d24/vmlinux-231825b2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d92b7bdbbe5c/bzImage-231825b2.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c81bea693d8cd125f5f2@syzkaller.appspotmail.com

------------[ cut here ]------------
Invalid notifier called!
WARNING: CPU: 1 PID: 24239 at kernel/notifier.c:79 notifier_call_chain+0x395/0x410 kernel/notifier.c:79
Modules linked in:
CPU: 1 UID: 0 PID: 24239 Comm: init Not tainted 6.13.0-rc2-syzkaller-00036-g231825b2e1ff #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:notifier_call_chain+0x395/0x410 kernel/notifier.c:79
Code: 00 44 89 f8 48 83 c4 30 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc e8 79 27 34 00 90 48 c7 c7 20 13 6c 8b e8 cc 72 f4 ff 90 <0f> 0b 90 90 e9 70 fd ff ff e8 5d 27 34 00 90 0f 0b 90 e9 2e fe ff
RSP: 0018:ffffc9000b5d7cc8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff88807d6558c8 RCX: ffffffff815a5079
RDX: ffff88806677a440 RSI: ffffffff815a5086 RDI: 0000000000000001
RBP: 00000000fffffffd R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 000000000006dc30 R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f27f7527500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005575df75b600 CR3: 0000000031b0c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 blocking_notifier_call_chain kernel/notifier.c:380 [inline]
 blocking_notifier_call_chain+0x69/0xa0 kernel/notifier.c:368
 kernel_shutdown_prepare kernel/reboot.c:299 [inline]
 kernel_power_off+0x1c/0xb0 kernel/reboot.c:702
 __do_sys_reboot+0x376/0x3e0 kernel/reboot.c:777
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f27f76808b4
Code: f0 ff ff 73 01 c3 48 8b 0d 71 55 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 89 fa be 69 19 12 28 bf ad de e1 fe b8 a9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 10 48 8b 15 45 55 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007fff502ede88 EFLAGS: 00000246 ORIG_RAX: 00000000000000a9
RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007f27f76808b4
RDX: 000000004321fedc RSI: 0000000028121969 RDI: 00000000fee1dead
RBP: 000000004321fedc R08: 0000000000000000 R09: 0000000000000000
R10: 00007fff502ede60 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff502edee8 R14: 000055e8723c1169 R15: 00007f27f785ea80
 </TASK>


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