WARNING in i2c_deregister_clients

Status: upstream: reported C repro on 2026/08/04 21:32
Reported-by: syzbot+fc76ef4437878d5ca8e6@syzkaller.appspotmail.com
First crash: 10d, last: 16h05m

Sample crash report:
------------[ 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
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>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/14 10:41 linux-6.6.y d27334b2888c b13552fe .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in i2c_deregister_clients
2026/08/04 21:31 linux-6.6.y aa0e49877a2e d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan WARNING in i2c_deregister_clients
* Struck through repros no longer work on HEAD.