------------[ cut here ]------------
WARNING: CPU: 1 PID: 12427 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: 12427 Comm: kworker/1:20 Not tainted 6.16.0-syzkaller #0 PREEMPT 
Hardware name: ARM-Versatile Express
Workqueue: md_misc mddev_delayed_delete
Call trace: 
[<80201a24>] (dump_backtrace) from [<80201b20>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:257)
 r7:00000000 r6:8281f77c r5:00000000 r4:8224bed0
[<80201b08>] (show_stack) from [<8021fb00>] (__dump_stack lib/dump_stack.c:94 [inline])
[<80201b08>] (show_stack) from [<8021fb00>] (dump_stack_lvl+0x54/0x7c lib/dump_stack.c:120)
[<8021faac>] (dump_stack_lvl) from [<8021fb40>] (dump_stack+0x18/0x1c lib/dump_stack.c:129)
 r5:00000000 r4:82a76d18
[<8021fb28>] (dump_stack) from [<80202624>] (vpanic+0x10c/0x360 kernel/panic.c:440)
[<80202518>] (vpanic) from [<802028ac>] (trace_suspend_resume+0x0/0xd8 kernel/panic.c:574)
 r7:808ba280
[<80202878>] (panic) from [<802548c4>] (check_panic_on_warn kernel/panic.c:333 [inline])
[<80202878>] (panic) from [<802548c4>] (get_taint+0x0/0x1c kernel/panic.c:328)
 r3:8280c684 r2:00000001 r1:822329a8 r0:8223a370
[<80254850>] (check_panic_on_warn) from [<80254a28>] (__warn+0x80/0x188 kernel/panic.c:845)
[<802549a8>] (__warn) from [<80254d18>] (warn_slowpath_fmt+0x1e8/0x1f4 kernel/panic.c:880)
 r8:00000009 r7:822a4838 r6:dfa11e54 r5:857b5400 r4:00000000
[<80254b34>] (warn_slowpath_fmt) from [<808ba280>] (refcount_warn_saturate+0x13c/0x174 lib/refcount.c:28)
 r10:833a4270 r9:83274845 r8:857b5400 r7:ddde2d40 r6:83274800 r5:8627021c
 r4:86270050
[<808ba144>] (refcount_warn_saturate) from [<819fdee8>] (__refcount_sub_and_test include/linux/refcount.h:400 [inline])
[<808ba144>] (refcount_warn_saturate) from [<819fdee8>] (__refcount_dec_and_test include/linux/refcount.h:432 [inline])
[<808ba144>] (refcount_warn_saturate) from [<819fdee8>] (refcount_dec_and_test include/linux/refcount.h:450 [inline])
[<808ba144>] (refcount_warn_saturate) from [<819fdee8>] (kref_put include/linux/kref.h:64 [inline])
[<808ba144>] (refcount_warn_saturate) from [<819fdee8>] (kobject_put+0x158/0x1f4 lib/kobject.c:737)
[<819fdd90>] (kobject_put) from [<81167c48>] (mddev_delayed_delete+0x14/0x18 drivers/md/md.c:5893)
 r7:ddde2d40 r6:83274800 r5:8627021c r4:86290d00
[<81167c34>] (mddev_delayed_delete) from [<8027a2d8>] (process_one_work+0x1b4/0x4f4 kernel/workqueue.c:3236)
[<8027a124>] (process_one_work) from [<8027af20>] (process_scheduled_works kernel/workqueue.c:3319 [inline])
[<8027a124>] (process_one_work) from [<8027af20>] (worker_thread+0x1fc/0x3d8 kernel/workqueue.c:3400)
 r10:61c88647 r9:857b5400 r8:86290d2c r7:82804d40 r6:ddde2d40 r5:ddde2d60
 r4:86290d00
[<8027ad24>] (worker_thread) from [<80281efc>] (kthread+0x12c/0x280 kernel/kthread.c:464)
 r10:00000000 r9:86290d00 r8:8027ad24 r7:dfac1e60 r6:86290100 r5:857b5400
 r4:00000001
[<80281dd0>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137)
Exception stack(0xdfa11fb0 to 0xdfa11ff8)
1fa0:                                     00000000 00000000 00000000 00000000
1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
1fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:80281dd0
 r4:85bf2200
Rebooting in 86400 seconds..