------------[ cut here ]------------
WARNING: CPU: 0 PID: 11388 at lib/percpu-refcount.c:113 __percpu_ref_exit+0x78/0x7c lib/percpu-refcount.c:113
Modules linked in:
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 11388 Comm: kworker/u4:1 Not tainted 5.12.0-rc3-syzkaller #0
Hardware name: ARM-Versatile Express
Workqueue: events_unbound io_ring_exit_work
Backtrace: 
[<81802550>] (dump_backtrace) from [<818027c4>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:252)
 r7:00000080 r6:60000093 r5:00000000 r4:82b58344
[<818027ac>] (show_stack) from [<81809e98>] (__dump_stack lib/dump_stack.c:79 [inline])
[<818027ac>] (show_stack) from [<81809e98>] (dump_stack+0xb8/0xe8 lib/dump_stack.c:120)
[<81809de0>] (dump_stack) from [<81803358>] (panic+0x130/0x378 kernel/panic.c:231)
 r7:81f48198 r6:82a390a4 r5:00000000 r4:82c6b0d0
[<81803228>] (panic) from [<802446f4>] (__warn+0xb0/0x164 kernel/panic.c:605)
 r3:82a2248c r2:00000000 r1:00000000 r0:81f48198
 r7:00000071
[<80244644>] (__warn) from [<81803608>] (warn_slowpath_fmt+0x68/0xd4 kernel/panic.c:628)
 r7:807f3158 r6:00000071 r5:81fa0208 r4:00000000
[<818035a4>] (warn_slowpath_fmt) from [<807f3158>] (__percpu_ref_exit+0x78/0x7c lib/percpu-refcount.c:113)
 r8:86df2980 r7:81f744cc r6:86e4d0c0 r5:a40692b4 r4:86e4d000
[<807f30e0>] (__percpu_ref_exit) from [<807f3174>] (percpu_ref_exit+0x18/0x64 lib/percpu-refcount.c:134)
 r5:86df2200 r4:86e4d000
[<807f315c>] (percpu_ref_exit) from [<80561c8c>] (io_ring_ctx_free fs/io_uring.c:8419 [inline])
[<807f315c>] (percpu_ref_exit) from [<80561c8c>] (io_ring_exit_work+0x304/0x4cc fs/io_uring.c:8565)
 r5:86e4d544 r4:86e4d318
[<80561988>] (io_ring_exit_work) from [<80269484>] (process_one_work+0x2d4/0x998 kernel/workqueue.c:2275)
 r10:00000088 r9:82a22498 r8:82bfd34e r7:83416000 r6:83420000 r5:86d28d00
 r4:86e4d544
[<802691b0>] (process_one_work) from [<80269bac>] (worker_thread+0x64/0x54c kernel/workqueue.c:2421)
 r10:00000088 r9:86e86000 r8:82a06d00 r7:83420038 r6:86d28d14 r5:83420000
 r4:86d28d00
[<80269b48>] (worker_thread) from [<80271d20>] (kthread+0x184/0x1a4 kernel/kthread.c:292)
 r10:86ddfe64 r9:86d28d00 r8:80269b48 r7:00000000 r6:86e86000 r5:86e62fc0
 r4:86d28e00
[<80271b9c>] (kthread) from [<80200114>] (ret_from_fork+0x14/0x20 arch/arm/kernel/entry-common.S:158)
Exception stack(0x86e87fb0 to 0x86e87ff8)
7fa0:                                     00000000 00000000 00000000 00000000
7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
7fe0: 00000000 00000000 00000000 00000000 00000013 00000000
 r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:80271b9c
 r4:86e62fc0
Rebooting in 86400 seconds..