------------[ cut here ]------------
WARNING: CPU: 1 PID: 5496 at lib/refcount.c:28 refcount_warn_saturate+0x13c/0x174 lib/refcount.c:28
refcount_t: underflow; use-after-free.
Modules linked in:
Kernel panic - not syncing: kernel: panic_on_warn set ...
CPU: 1 UID: 0 PID: 5496 Comm: kworker/1:12 Not tainted 6.16.0-syzkaller #0 PREEMPT 
Hardware name: ARM-Versatile Express
Workqueue: md_misc mddev_delayed_delete
Call trace: 
[<80201a20>] (dump_backtrace) from [<80201b1c>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257)
 r7:00000000 r6:8281fa3c r5:00000000 r4:8224a6e0
[<80201b04>] (show_stack) from [<8021fa84>] (__dump_stack lib/dump_stack.c:94 [inline])
[<80201b04>] (show_stack) from [<8021fa84>] (dump_stack_lvl+0x54/0x7c lib/dump_stack.c:120)
[<8021fa30>] (dump_stack_lvl) from [<8021fac4>] (dump_stack+0x18/0x1c lib/dump_stack.c:129)
 r5:00000000 r4:82a6cd18
[<8021faac>] (dump_stack) from [<80202634>] (panic+0x120/0x374 kernel/panic.c:442)
[<80202514>] (panic) from [<802548dc>] (check_panic_on_warn kernel/panic.c:333 [inline])
[<80202514>] (panic) from [<802548dc>] (get_taint+0x0/0x1c kernel/panic.c:328)
 r3:8280c684 r2:00000001 r1:82231124 r0:82238aec
 r7:808b1a34
[<80254868>] (check_panic_on_warn) from [<80254a40>] (__warn+0x80/0x188 kernel/panic.c:837)
[<802549c0>] (__warn) from [<80254d30>] (warn_slowpath_fmt+0x1e8/0x1f4 kernel/panic.c:872)
 r8:00000009 r7:822a2840 r6:dfbd5e54 r5:86e31800 r4:00000000
[<80254b4c>] (warn_slowpath_fmt) from [<808b1a34>] (refcount_warn_saturate+0x13c/0x174 lib/refcount.c:28)
 r10:83367170 r9:8326fa25 r8:86e31800 r7:ddde2d40 r6:8326fa00 r5:85fd021c
 r4:85fd0050
[<808b18f8>] (refcount_warn_saturate) from [<819f1fc8>] (__refcount_sub_and_test include/linux/refcount.h:400 [inline])
[<808b18f8>] (refcount_warn_saturate) from [<819f1fc8>] (__refcount_dec_and_test include/linux/refcount.h:432 [inline])
[<808b18f8>] (refcount_warn_saturate) from [<819f1fc8>] (refcount_dec_and_test include/linux/refcount.h:450 [inline])
[<808b18f8>] (refcount_warn_saturate) from [<819f1fc8>] (kref_put include/linux/kref.h:64 [inline])
[<808b18f8>] (refcount_warn_saturate) from [<819f1fc8>] (kobject_put+0x158/0x1f4 lib/kobject.c:737)
[<819f1e70>] (kobject_put) from [<81158e48>] (mddev_delayed_delete+0x14/0x18 drivers/md/md.c:5893)
 r7:ddde2d40 r6:8326fa00 r5:85fd021c r4:8496d500
[<81158e34>] (mddev_delayed_delete) from [<8027a468>] (process_one_work+0x1b4/0x4f4 kernel/workqueue.c:3238)
[<8027a2b4>] (process_one_work) from [<8027b0b0>] (process_scheduled_works kernel/workqueue.c:3321 [inline])
[<8027a2b4>] (process_one_work) from [<8027b0b0>] (worker_thread+0x1fc/0x3d8 kernel/workqueue.c:3402)
 r10:61c88647 r9:86e31800 r8:8496d52c r7:82804d40 r6:ddde2d40 r5:ddde2d60
 r4:8496d500
[<8027aeb4>] (worker_thread) from [<80282130>] (kthread+0x12c/0x280 kernel/kthread.c:464)
 r10:00000000 r9:8496d500 r8:8027aeb4 r7:dfcc5e60 r6:85dbfe00 r5:86e31800
 r4:00000001
[<80282004>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137)
Exception stack(0xdfbd5fb0 to 0xdfbd5ff8)
5fa0:                                     00000000 00000000 00000000 00000000
5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:80282004
 r4:86fa1f00
Rebooting in 86400 seconds..