[v6.6] WARNING in i2c_deregister_clients

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: aa0e49877a2e Linux 6.6.148
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14267649580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f0bc3d90c30838b5
dashboard link: https://syzkaller.appspot.com/bug?extid=fc76ef4437878d5ca8e6
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f83b390cfc1f/disk-aa0e4987.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1d4bdb338edd/vmlinux-aa0e4987.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3f57c1d51ee3/bzImage-aa0e4987.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fc76ef...@syzkaller.appspotmail.com

------------[ cut here ]------------
Device '1-002c' does not have a release() function, it is broken and must be fixed. See Documentation/core-api/kobject.rst.
WARNING: CPU: 0 PID: 5812 at drivers/base/core.c:2518 device_release+0x1d5/0x1e0 drivers/base/core.c:2517
Modules linked in:
CPU: 0 PID: 5812 Comm: kworker/0:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:device_release+0x1d5/0x1e0 drivers/base/core.c:2517
Code: 39 fc 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 5d b6 91 fc 4d 8b 3e 48 c7 c7 00 e3 41 8b 4c 89 fe e8 8b 01 03 fc <0f> 0b e9 e0 fe ff ff 0f 1f 40 00 f3 0f 1e fa 41 57 41 56 41 54 53
RSP: 0018:ffffc9000492f208 EFLAGS: 00010246
RAX: 8aa39404719ca000 RBX: ffff888030ab7c00 RCX: 0000000000100000
RDX: ffffc90018109000 RSI: 00000000000b90bd RDI: 00000000000b90be
RBP: 0000000000000000 R08: ffffc9000492ef07 R09: 1ffff92000925de0
R10: dffffc0000000000 R11: fffff52000925de1 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88814724f020 R15: ffff888143ff22d0
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd507c5618 CR3: 00000000263ac000 CR4: 00000000003506f0
Call Trace:
<TASK>
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x21b/0x450 lib/kobject.c:737
i2c_deregister_clients+0x27b/0x380 drivers/i2c/i2c-core-base.c:1775
i2c_del_adapter+0x115/0x430 drivers/i2c/i2c-core-base.c:1813
dvb_usb_i2c_exit+0x64/0xb0 drivers/media/usb/dvb-usb/dvb-usb-i2c.c:46
dvb_usb_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:144 [inline]
dvb_usb_device_exit+0x1cc/0x340 drivers/media/usb/dvb-usb/dvb-usb-init.c:338
usb_unbind_interface+0x207/0x870 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:628 [inline]
__device_release_driver drivers/base/dd.c:1351 [inline]
device_release_driver_internal+0x458/0x6f0 drivers/base/dd.c:1374
bus_remove_device+0x43b/0x520 drivers/base/bus.c:624
device_del+0x51f/0x910 drivers/base/core.c:3889
usb_disable_device+0x3ee/0x8a0 drivers/usb/core/message.c:1474
usb_disconnect+0x340/0x8a0 drivers/usb/core/hub.c:2315
hub_port_connect drivers/usb/core/hub.c:5369 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5669 [inline]
port_event drivers/usb/core/hub.c:5833 [inline]
hub_event+0x1d69/0x4a80 drivers/usb/core/hub.c:5915
process_one_work kernel/workqueue.c:2657 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
</TASK>


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: d27334b2888c Linux 6.6.151
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=153b0279580000

kernel config: https://syzkaller.appspot.com/x/.config?x=f0bc3d90c30838b5
dashboard link: https://syzkaller.appspot.com/bug?extid=fc76ef4437878d5ca8e6
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=147df149580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16b9fac6580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/695139abd971/disk-d27334b2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b11fc121442a/vmlinux-d27334b2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e226f54f9286/bzImage-d27334b2.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fc76ef...@syzkaller.appspotmail.com

------------[ cut here ]------------
Device '1-002c' does not have a release() function, it is broken and must be fixed. See Documentation/core-api/kobject.rst.

WARNING: CPU: 1 PID: 5960 at drivers/base/core.c:2518 device_release+0x1d5/0x1e0 drivers/base/core.c:2517
Modules linked in:
CPU: 1 PID: 5960 Comm: kworker/1:5 Not tainted syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:device_release+0x1d5/0x1e0 drivers/base/core.c:2517

Code: 37 fc 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 ed 0c 90 fc 4d 8b 3e 48 c7 c7 00 0a 42 8b 4c 89 fe e8 bb 56 01 fc <0f> 0b e9 e0 fe ff ff 0f 1f 40 00 f3 0f 1e fa 41 57 41 56 41 54 53
RSP: 0018:ffffc90003407208 EFLAGS: 00010246
RAX: 47cfb7fe0ee46d00 RBX: ffff888146af3000 RCX: ffff8880787fbc00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: 0000000000000000 R08: ffffffff911ed5f7 R09: 1ffffffff223dabe
R10: dffffc0000000000 R11: fffffbfff223dabf R12: dffffc0000000000
R13: 0000000000000000 R14: ffff888076cf1020 R15: ffff888019a88c80
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007fff18a90f98 CR3: 00000000303e8000 CR4: 00000000003506e0

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
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