------------[ cut here ]------------ WARNING: CPU: 0 PID: 14995 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: 0 PID: 14995 Comm: kworker/0:1 Not tainted 5.8.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events io_ring_exit_work Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 panic+0x2e3/0x75c kernel/panic.c:231 __warn.cold+0x20/0x45 kernel/panic.c:600 report_bug+0x1bd/0x210 lib/bug.c:198 handle_bug+0x38/0x90 arch/x86/kernel/traps.c:235 exc_invalid_op+0x13/0x40 arch/x86/kernel/traps.c:255 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:540 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 c2 d6 dc fd e8 bd d6 dc fd <0f> 0b eb c2 4c 89 e7 e8 41 3b 1c fe eb dc e8 ba 3a 1c fe eb aa 4c RSP: 0018:ffffc90015f97ca0 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffff88808e74f000 RCX: ffffffff8396e56d RDX: ffff8880764f8040 RSI: ffffffff8396e5d3 RDI: ffff88808e74f018 RBP: 0000607f5168dff8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88808e74f008 R13: ffff88808e74f1a8 R14: 1ffff11011ce9e20 R15: ffff88808e74f000 io_ring_ctx_free fs/io_uring.c:7362 [inline] io_ring_exit_work+0x4b2/0x750 fs/io_uring.c:7427 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Kernel Offset: disabled Rebooting in 86400 seconds..