[syzbot] [usb?] WARNING in dummy_free_request (2)

[syzbot] [usb?] WARNING in dummy_free_request (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    cc2b5f627e8c Add linux-next specific files for 20260714
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=159922a9580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2290ccbf984c524f
dashboard link: https://syzkaller.appspot.com/bug?extid=c73e1942197af9f54ca3
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/6836f8efb1da/disk-cc2b5f62.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0109d3477cc7/vmlinux-cc2b5f62.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c2e49e350bbf/bzImage-cc2b5f62.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c73e1942197af9f54ca3@syzkaller.appspotmail.com

configfs-gadget.g1 gadget.0: uvc: uvc_function_bind()
configfs-gadget.g1 gadget.0: uvc: Unable to allocate streaming EP
------------[ cut here ]------------
!list_empty(&req->queue)
WARNING: drivers/usb/gadget/udc/dummy_hcd.c:691 at dummy_free_request+0x6f/0x80 drivers/usb/gadget/udc/dummy_hcd.c:691, CPU#1: syz.3.795/7609
Modules linked in:
CPU: 1 UID: 0 PID: 7609 Comm: syz.3.795 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:dummy_free_request+0x6f/0x80 drivers/usb/gadget/udc/dummy_hcd.c:691
Code: 75 22 e8 14 e0 8b fa 48 89 df 5b 41 5e e9 89 5c ec fa e8 04 e0 8b fa 90 0f 0b 90 5b 41 5e c3 cc cc cc cc cc e8 f2 df 8b fa 90 <0f> 0b 90 eb d8 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
RSP: 0018:ffffc900087cf730 EFLAGS: 00010287
RAX: ffffffff8739c3be RBX: ffff88803a585ff0 RCX: 0000000000080000
RDX: ffffc9000759a000 RSI: 00000000000009d6 RDI: 00000000000009d7
RBP: 00000000ffffffea R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff8739c350 R12: ffff88805f2f0520
R13: ffff888021b808d8 R14: ffff8880295e00a8 R15: ffff8880295e0c98
FS:  00007f8a2e8b66c0(0000) GS:ffff888125af2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc44f5ab050 CR3: 0000000024f34000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 uvc_function_bind+0xe5d/0x15a0 drivers/usb/gadget/function/f_uvc.c:893
 usb_add_function+0x290/0x930 drivers/usb/gadget/composite.c:333
 configfs_composite_bind+0xde0/0x1410 drivers/usb/gadget/configfs.c:1802
 gadget_bind_driver+0x2ca/0x9e0 drivers/usb/gadget/udc/core.c:1662
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x254/0xae0 drivers/base/dd.c:706
 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
 __driver_attach+0x339/0x600 drivers/base/dd.c:1292
 bus_for_each_dev+0x23e/0x2c0 drivers/base/bus.c:383
 bus_add_driver+0x348/0x670 drivers/base/bus.c:763
 driver_register+0x23a/0x320 drivers/base/driver.c:174
 usb_gadget_register_driver_owner+0xf9/0x270 drivers/usb/gadget/udc/core.c:1752
 gadget_dev_desc_UDC_store+0x1c9/0x2f0 drivers/usb/gadget/configfs.c:300
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x33a/0x430 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x61e/0xbb0 fs/read_write.c:687
 ksys_write+0x156/0x270 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x17b/0x530 arch/x86/entry/syscall_64.c:85
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8a3065de99
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8a2e8b6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8a308e5fa0 RCX: 00007f8a3065de99
RDX: 000000000000000b RSI: 0000200000000880 RDI: 0000000000000003
RBP: 00007f8a306f3eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8a308e6038 R14: 00007f8a308e5fa0 R15: 00007ffcfa6f54e8
 </TASK>


---
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Re: [syzbot] [usb?] WARNING in dummy_free_request (2)

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    e2d5e23967d0 Merge branch 'for-next/core' into for-kernelci
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=179d8649580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=72c97575381cec47
dashboard link: https://syzkaller.appspot.com/bug?extid=c73e1942197af9f54ca3
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: arm64
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=13b62db9580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17a12c9e580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/294cdababe04/disk-e2d5e239.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3e828c9fa51b/vmlinux-e2d5e239.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ffd7614ad310/Image-e2d5e239.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c73e1942197af9f54ca3@syzkaller.appspotmail.com

gadgetfs: suspended from state 3
gadgetfs: disconnected
------------[ cut here ]------------
WARNING: drivers/usb/gadget/udc/dummy_hcd.c:710 at dummy_free_request+0x7c/0x84 drivers/usb/gadget/udc/dummy_hcd.c:710, CPU#0: syz.0.32/4939
Modules linked in:
CPU: 0 UID: 0 PID: 4939 Comm: syz.0.32 Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : dummy_free_request+0x7c/0x84 drivers/usb/gadget/udc/dummy_hcd.c:710
lr : dummy_free_request+0x7c/0x84 drivers/usb/gadget/udc/dummy_hcd.c:710
sp : ffff8000962579d0
x29: ffff8000962579d0 x28: 1fffe000195c4a01 x27: ffff0000cae25008
x26: 1fffe0001a0e2408 x25: 1fffe0001952998b x24: 1fffe000195299aa
x23: dfff800000000000 x22: ffff800088b07eb8 x21: ffff800087332200
x20: ffff0000ca94c068 x19: ffff0000d866f900 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
x14: 00000000868e5610 x13: 0000000000000001 x12: 0000000000000000
x11: ffff800080156ee8 x10: 0000000000000003 x9 : 0000000000000000
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000008 x3 : ffff8000835a7208
x2 : 0000000000000001 x1 : ffff0000c82cba80 x0 : 0000000000000000
Call trace:
 dummy_free_request+0x7c/0x84 drivers/usb/gadget/udc/dummy_hcd.c:710 (P)
 usb_ep_free_request+0x108/0x3fc drivers/usb/gadget/udc/core.c:221
 gadgetfs_unbind+0x19c/0x1f0 drivers/usb/gadget/legacy/inode.c:1661
 gadget_unbind_driver+0x188/0x790 drivers/usb/gadget/udc/core.c:1724
 device_remove+0xc4/0x134 drivers/base/dd.c:616
 __device_release_driver drivers/base/dd.c:1349 [inline]
 device_release_driver_internal+0x124/0x20c drivers/base/dd.c:1372
 driver_detach+0x124/0x1b4 drivers/base/dd.c:1435
 bus_remove_driver+0x124/0x22c drivers/base/bus.c:832
 driver_unregister+0x78/0xac drivers/base/driver.c:202
 usb_gadget_unregister_driver+0x50/0x78 drivers/usb/gadget/udc/core.c:1784
 dev_release+0x8c/0x15c drivers/usb/gadget/legacy/inode.c:1198
 __fput+0x338/0x74c fs/file_table.c:512
 ____fput+0x20/0x30 fs/file_table.c:540
 task_work_run+0x1cc/0x25c kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x10c/0x17c kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 arm64_syscall_exit_to_user_mode arch/arm64/kernel/entry-common.c:88 [inline]
 el0_svc+0x18c/0x260 arch/arm64/kernel/entry-common.c:737
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594
irq event stamp: 2192
hardirqs last  enabled at (2191): [<ffff80008690a7dc>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:187 [inline]
hardirqs last  enabled at (2191): [<ffff80008690a7dc>] _raw_spin_unlock_irq+0x30/0x80 kernel/locking/spinlock.c:206
hardirqs last disabled at (2192): [<ffff8000868e5428>] el1_brk64+0x20/0x54 arch/arm64/kernel/entry-common.c:425
softirqs last  enabled at (1170): [<ffff80008030ff18>] softirq_handle_end kernel/softirq.c:468 [inline]
softirqs last  enabled at (1170): [<ffff80008030ff18>] handle_softirqs+0xc28/0xd98 kernel/softirq.c:650
softirqs last disabled at (1161): [<ffff8000800204c0>] __do_softirq+0x14/0x20 kernel/softirq.c:656
---[ end trace 0000000000000000 ]---
==================================================================
BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x3c/0x1b8 lib/list_debug.c:49
Read of size 8 at addr ffff0000d866f908 by task syz.0.32/4939

CPU: 1 UID: 0 PID: 4939 Comm: syz.0.32 Tainted: G        W           syzkaller #0 PREEMPT 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 print_address_description+0xb0/0x238 mm/kasan/report.c:378
 print_report+0x68/0x84 mm/kasan/report.c:482
 kasan_report+0x8c/0xc4 mm/kasan/report.c:595
 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381
 __list_del_entry_valid_or_report+0x3c/0x1b8 lib/list_debug.c:49
 __list_del_entry_valid include/linux/list.h:132 [inline]
 __list_del_entry include/linux/list.h:246 [inline]
 list_del_init include/linux/list.h:318 [inline]
 nuke+0x60/0x194 drivers/usb/gadget/udc/dummy_hcd.c:360
 stop_activity drivers/usb/gadget/udc/dummy_hcd.c:379 [inline]
 dummy_udc_stop+0xe4/0x180 drivers/usb/gadget/udc/dummy_hcd.c:1057
 usb_gadget_udc_stop_locked drivers/usb/gadget/udc/core.c:1265 [inline]
 gadget_unbind_driver+0x204/0x790 drivers/usb/gadget/udc/core.c:1727
 device_remove+0xc4/0x134 drivers/base/dd.c:616
 __device_release_driver drivers/base/dd.c:1349 [inline]
 device_release_driver_internal+0x124/0x20c drivers/base/dd.c:1372
 driver_detach+0x124/0x1b4 drivers/base/dd.c:1435
 bus_remove_driver+0x124/0x22c drivers/base/bus.c:832
 driver_unregister+0x78/0xac drivers/base/driver.c:202
 usb_gadget_unregister_driver+0x50/0x78 drivers/usb/gadget/udc/core.c:1784
 dev_release+0x8c/0x15c drivers/usb/gadget/legacy/inode.c:1198
 __fput+0x338/0x74c fs/file_table.c:512
 ____fput+0x20/0x30 fs/file_table.c:540
 task_work_run+0x1cc/0x25c kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x10c/0x17c kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 arm64_syscall_exit_to_user_mode arch/arm64/kernel/entry-common.c:88 [inline]
 el0_svc+0x18c/0x260 arch/arm64/kernel/entry-common.c:737
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594

Allocated by task 4939:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x40/0x78 mm/kasan/common.c:78
 kasan_save_alloc_info+0x44/0x54 mm/kasan/generic.c:570
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x9c/0xb4 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_noprof+0x2e8/0x5ec mm/slub.c:5489
 _kmalloc_noprof include/linux/slab.h:988 [inline]
 _kzalloc_noprof include/linux/slab.h:1309 [inline]
 dummy_alloc_request+0x88/0x128 drivers/usb/gadget/udc/dummy_hcd.c:693
 usb_ep_alloc_request+0x74/0x480 drivers/usb/gadget/udc/core.c:197
 gadgetfs_bind+0x104/0x75c drivers/usb/gadget/legacy/inode.c:1686
 gadget_bind_driver+0x274/0x834 drivers/usb/gadget/udc/core.c:1662
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x29c/0x800 drivers/base/dd.c:706
 __driver_probe_device+0x1e0/0x350 drivers/base/dd.c:868
 driver_probe_device+0x6c/0x19c drivers/base/dd.c:898
 __driver_attach+0x168/0x384 drivers/base/dd.c:1292
 bus_for_each_dev+0x128/0x1b4 drivers/base/bus.c:383
 driver_attach+0x50/0x60 drivers/base/dd.c:1310
 bus_add_driver+0x208/0x500 drivers/base/bus.c:763
 driver_register+0x220/0x310 drivers/base/driver.c:174
 usb_gadget_register_driver_owner+0xf0/0x25c drivers/usb/gadget/udc/core.c:1752
 dev_config+0x91c/0xcc0 drivers/usb/gadget/legacy/inode.c:1883
 vfs_write+0x2a4/0xa0c fs/read_write.c:685
 ksys_write+0x12c/0x228 fs/read_write.c:739
 __do_sys_write fs/read_write.c:750 [inline]
 __se_sys_write fs/read_write.c:747 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:747
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594

Freed by task 4939:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x40/0x78 mm/kasan/common.c:78
 kasan_save_free_info+0x58/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x74/0xa4 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2677 [inline]
 slab_free mm/slub.c:6377 [inline]
 kfree+0x188/0x690 mm/slub.c:6692
 dummy_free_request+0x5c/0x84 drivers/usb/gadget/udc/dummy_hcd.c:711
 usb_ep_free_request+0x108/0x3fc drivers/usb/gadget/udc/core.c:221
 gadgetfs_unbind+0x19c/0x1f0 drivers/usb/gadget/legacy/inode.c:1661
 gadget_unbind_driver+0x188/0x790 drivers/usb/gadget/udc/core.c:1724
 device_remove+0xc4/0x134 drivers/base/dd.c:616
 __device_release_driver drivers/base/dd.c:1349 [inline]
 device_release_driver_internal+0x124/0x20c drivers/base/dd.c:1372
 driver_detach+0x124/0x1b4 drivers/base/dd.c:1435
 bus_remove_driver+0x124/0x22c drivers/base/bus.c:832
 driver_unregister+0x78/0xac drivers/base/driver.c:202
 usb_gadget_unregister_driver+0x50/0x78 drivers/usb/gadget/udc/core.c:1784
 dev_release+0x8c/0x15c drivers/usb/gadget/legacy/inode.c:1198
 __fput+0x338/0x74c fs/file_table.c:512
 ____fput+0x20/0x30 fs/file_table.c:540
 task_work_run+0x1cc/0x25c kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x10c/0x17c kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 arm64_syscall_exit_to_user_mode arch/arm64/kernel/entry-common.c:88 [inline]
 el0_svc+0x18c/0x260 arch/arm64/kernel/entry-common.c:737
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594

The buggy address belongs to the object at ffff0000d866f900
 which belongs to the cache kmalloc-128 of size 128
The buggy address is located 8 bytes inside of
 freed 128-byte region [ffff0000d866f900, ffff0000d866f980)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11866f
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 05ffc00000000000 ffff0000c0001a00 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000d866f800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000d866f880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff0000d866f900: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff0000d866f980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000d866fa00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
list_del corruption, ffff0000d866f900->next is NULL
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:53!
Internal error: Oops - BUG: 00000000f2000800 [#1]  SMP
Modules linked in:
CPU: 1 UID: 0 PID: 4939 Comm: syz.0.32 Tainted: G    B   W           syzkaller #0 PREEMPT 
Tainted: [B]=BAD_PAGE, [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
pstate: 634000c5 (nZCv daIF +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : __list_del_entry_valid_or_report+0xec/0x1b8 lib/list_debug.c:52
lr : __list_del_entry_valid_or_report+0xec/0x1b8 lib/list_debug.c:52
sp : ffff8000962579c0
x29: ffff8000962579c0 x28: 1fffe000195c4a01 x27: ffff0000cae25008
x26: 1fffe000195c4a00 x25: 00000000ffffff94 x24: 1fffe00019529808
x23: dfff800000000000 x22: dfff800000000000 x21: 0338032e0000134b
x20: 0000000000000000 x19: ffff0000d866f900 x18: 0000000000000000
x17: 3d3d3d3d3d3d3d3d x16: 3d3d3d3d3d3d3d3d x15: 3d3d3d3d3d3d3d3d
x14: 3d3d3d3d3d3d3d3d x13: 0000000000000001 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000002 x9 : bfb6b4227df68700
x8 : bfb6b4227df68700 x7 : 0000000000000001 x6 : ffff80008048de94
x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff800080498bc8
x2 : 0000000100000001 x1 : ffff0000c82cba80 x0 : 0000000000000033
Call trace:
 __list_del_entry_valid_or_report+0xec/0x1b8 lib/list_debug.c:52 (P)
 __list_del_entry_valid include/linux/list.h:132 [inline]
 __list_del_entry include/linux/list.h:246 [inline]
 list_del_init include/linux/list.h:318 [inline]
 nuke+0x60/0x194 drivers/usb/gadget/udc/dummy_hcd.c:360
 stop_activity drivers/usb/gadget/udc/dummy_hcd.c:379 [inline]
 dummy_udc_stop+0xe4/0x180 drivers/usb/gadget/udc/dummy_hcd.c:1057
 usb_gadget_udc_stop_locked drivers/usb/gadget/udc/core.c:1265 [inline]
 gadget_unbind_driver+0x204/0x790 drivers/usb/gadget/udc/core.c:1727
 device_remove+0xc4/0x134 drivers/base/dd.c:616
 __device_release_driver drivers/base/dd.c:1349 [inline]
 device_release_driver_internal+0x124/0x20c drivers/base/dd.c:1372
 driver_detach+0x124/0x1b4 drivers/base/dd.c:1435
 bus_remove_driver+0x124/0x22c drivers/base/bus.c:832
 driver_unregister+0x78/0xac drivers/base/driver.c:202
 usb_gadget_unregister_driver+0x50/0x78 drivers/usb/gadget/udc/core.c:1784
 dev_release+0x8c/0x15c drivers/usb/gadget/legacy/inode.c:1198
 __fput+0x338/0x74c fs/file_table.c:512
 ____fput+0x20/0x30 fs/file_table.c:540
 task_work_run+0x1cc/0x25c kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x10c/0x17c kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 arm64_syscall_exit_to_user_mode arch/arm64/kernel/entry-common.c:88 [inline]
 el0_svc+0x18c/0x260 arch/arm64/kernel/entry-common.c:737
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594
Code: f0029ac0 91328000 aa1303e1 979c21eb (d4210000) 
---[ end trace 0000000000000000 ]---


---
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