[moderation] [fs?] WARNING in __simple_recursive_removal

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4235cb24ec1e Merge tag 'vfs-7.2-rc5.fixes' of git://git.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=165e1632580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f221a1b5d497ed15
dashboard link: https://syzkaller.appspot.com/bug?extid=9a02195d405b2a800a28
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386
CC: [da...@kernel.org drive...@lists.linux.dev gre...@linuxfoundation.org linux-...@vger.kernel.org linux-...@vger.kernel.org raf...@kernel.org]

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-4235cb24.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/68eef4847f46/vmlinux-4235cb24.xz
kernel image: https://storage.googleapis.com/syzbot-assets/77e73df69f7f/bzImage-4235cb24.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9a0219...@syzkaller.appspotmail.com

i2c i2c-2: failure reading status
ucsi-stm32g0-i2c 2-0003: i2c read 03, 00 error: -5
------------[ cut here ]------------
inode->i_nlink == 0
WARNING: fs/inode.c:408 at drop_nlink+0xb6/0xe0 fs/inode.c:408, CPU#2: syz.3.2766/15846
Modules linked in:
CPU: 2 UID: 0 PID: 15846 Comm: syz.3.2766 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:drop_nlink+0xb6/0xe0 fs/inode.c:408
Code: 08 00 00 00 48 8d bb 98 07 00 00 e8 04 92 e3 ff f0 48 ff 83 98 07 00 00 e8 57 ff 73 ff 5b 5d e9 50 f4 25 09 e8 4b ff 73 ff 90 <0f> 0b 90 c7 45 48 ff ff ff ff e8 3b ff 73 ff 5b 5d c3 cc cc cc cc
RSP: 0018:ffffc90000baf628 EFLAGS: 00010287
RAX: 00000000000040d2 RBX: 0000000000000000 RCX: ffffc90031157000
RDX: 0000000000080000 RSI: ffffffff8295ad15 RDI: ffff88801cf40000
RBP: ffff88804451db70 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88804451db70
R13: dffffc0000000000 R14: ffff888013e0fa70 R15: ffff8880506ec358
FS: 0000000000000000(0000) GS:ffff888096de3000(0063) knlGS:00000000f53c4b40
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000005720e1fc CR3: 000000002a78a000 CR4: 0000000000352ef0
Call Trace:
<TASK>
__simple_recursive_removal+0x4c2/0x5c0 fs/libfs.c:631
debugfs_remove+0x5d/0x80 fs/debugfs/inode.c:781
i2c_device_probe+0x6e2/0xd10 drivers/i2c/i2c-core-base.c:610
call_driver_probe drivers/base/dd.c:628 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:706
__driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
__device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x64/0x160 drivers/base/bus.c:620
device_add+0x121d/0x1970 drivers/base/core.c:3772
i2c_new_client_device+0x660/0xd30 drivers/i2c/i2c-core-base.c:1019
new_device_store+0x20f/0x420 drivers/i2c/i2c-core-base.c:1307
dev_attr_store+0x58/0x80 drivers/base/core.c:2505
sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x6ac/0x1050 fs/read_write.c:687
ksys_write+0x12a/0x250 fs/read_write.c:739
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0xe7/0x970 arch/x86/entry/syscall_32.c:307
do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f47fec
Code: Unable to access opcode bytes at 0xf7f47fc2.
RSP: 002b:00000000f53c450c EFLAGS: 00000292 ORIG_RAX: 0000000000000004
RAX: ffffffffffffffda RBX: 000000000000000b RCX: 0000000080000a00
RDX: 0000000000000011 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>


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