------------[ cut here ]------------ WARNING: CPU: 1 PID: 4625 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: 4625 Comm: kworker/1:7 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 r4:8224bc00 [<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 r1:822326d8 r0:8223a0a0 [<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 r7:822a4568 r6:dfad5e54 r5:84cb9800 r4:00000000 [<80254b34>] (warn_slowpath_fmt) from [<808ba280>] (refcount_warn_saturate+0x13c/0x174 lib/refcount.c:28) r10:83849270 r9:83810c45 r8:84cb9800 r7:ddde2d40 r6:83810c00 r5:84e9121c r4:84e91050 [<808ba144>] (refcount_warn_saturate) from [<819fd868>] (__refcount_sub_and_test include/linux/refcount.h:400 [inline]) [<808ba144>] (refcount_warn_saturate) from [<819fd868>] (__refcount_dec_and_test include/linux/refcount.h:432 [inline]) [<808ba144>] (refcount_warn_saturate) from [<819fd868>] (refcount_dec_and_test include/linux/refcount.h:450 [inline]) [<808ba144>] (refcount_warn_saturate) from [<819fd868>] (kref_put include/linux/kref.h:64 [inline]) [<808ba144>] (refcount_warn_saturate) from [<819fd868>] (kobject_put+0x158/0x1f4 lib/kobject.c:737) [<819fd710>] (kobject_put) from [<81167c68>] (mddev_delayed_delete+0x14/0x18 drivers/md/md.c:5893) r7:ddde2d40 r6:83810c00 r5:84e9121c r4:8594ae00 [<81167c54>] (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 r9:84cb9800 r8:8594ae2c r7:82804d40 r6:ddde2d40 r5:ddde2d60 r4:8594ae00 [<8027ad24>] (worker_thread) from [<80281efc>] (kthread+0x12c/0x280 kernel/kthread.c:464) r10:00000000 r9:8594ae00 r8:8027ad24 r7:dfaa1e60 r6:863cf880 r5:84cb9800 r4:00000001 [<80281dd0>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:137) Exception stack(0xdfad5fb0 to 0xdfad5ff8) 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 r5:80281dd0 r4:84e66300 Rebooting in 86400 seconds..