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WARNING: CPU: 1 PID: 21793 at lib/percpu-refcount.c:112 percpu_ref_exit+0xa3/0xd0 lib/percpu-refcount.c:112
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 21793 Comm: kworker/u4:3 Not tainted 5.9.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound io_ring_exit_work
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x198/0x1fd lib/dump_stack.c:118
 panic+0x347/0x7c0 kernel/panic.c:231
 __warn.cold+0x20/0x46 kernel/panic.c:600
 report_bug+0x1bd/0x210 lib/bug.c:198
 handle_bug+0x38/0x90 arch/x86/kernel/traps.c:234
 exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254
 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536
RIP: 0010:percpu_ref_exit+0xa3/0xd0 lib/percpu-refcount.c:112
Code: 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 1a 48 c7 43 08 03 00 00 00 5b 5d 41 5c e9 d2 83 d9 fd e8 cd 83 d9 fd <0f> 0b eb c2 4c 89 e7 e8 71 8b 19 fe eb dc e8 ea 8a 19 fe eb aa 4c
RSP: 0018:ffffc900068c7ca8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88809c7e8000 RCX: ffffffff839ac9ad
RDX: ffff88805b3824c0 RSI: ffffffff839aca13 RDI: ffff88809c7e8018
RBP: 0000607f516a4e48 R08: 0000000000000001 R09: ffffffff8c5f4af7
R10: 0000000000000000 R11: 000000000000016e R12: ffff88809c7e8008
R13: 0000000000000000 R14: ffff88809c7e8101 R15: 0000000000000005
 io_ring_ctx_free fs/io_uring.c:7892 [inline]
 io_ring_exit_work+0x466/0x6d0 fs/io_uring.c:7954
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Kernel Offset: disabled
Rebooting in 86400 seconds..