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WARNING: CPU: 1 PID: 9630 at lib/percpu-refcount.c:111 percpu_ref_exit+0xa3/0xd0 lib/percpu-refcount.c:111
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 9630 Comm: syz-executor.5 Not tainted 5.6.0-rc3-next-20200228-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:221
 __warn.cold+0x2f/0x35 kernel/panic.c:582
 report_bug+0x27b/0x2f0 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:175 [inline]
 fixup_bug arch/x86/kernel/traps.c:170 [inline]
 do_error_trap+0x12b/0x220 arch/x86/kernel/traps.c:267
 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:percpu_ref_exit+0xa3/0xd0 lib/percpu-refcount.c:111
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 f2 6e e3 fd e8 ed 6e e3 fd <0f> 0b eb c2 4c 89 e7 e8 01 90 20 fe eb dc e8 7a 8f 20 fe eb aa 4c
RSP: 0018:ffffc900074a7d68 EFLAGS: 00010293
RAX: ffff88804c9b6100 RBX: ffff888053f46a10 RCX: ffffffff838f262d
RDX: 0000000000000000 RSI: ffffffff838f2693 RDI: ffff888053f46a28
RBP: 0000607f516ebe38 R08: ffff88804c9b6100 R09: ffffed100a7e8d4a
R10: ffffed100a7e8d49 R11: ffff888053f46a4f R12: ffff888053f46a18
R13: ffff8880a45731a0 R14: ffff8880a4573000 R15: ffff8880547cc9c0
 io_sqe_files_unregister+0x8a/0x2f0 fs/io_uring.c:5412
 io_ring_ctx_free fs/io_uring.c:6408 [inline]
 io_ring_ctx_wait_and_kill+0x4b5/0xa10 fs/io_uring.c:6499
 io_uring_release+0x3e/0x50 fs/io_uring.c:6507
 __fput+0x2da/0x850 fs/file_table.c:280
 task_work_run+0x13f/0x1b0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2fa/0x360 arch/x86/entry/common.c:165
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x672/0x790 arch/x86/entry/common.c:305
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4163e1
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007ffcc0c0a3e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00000000004163e1
RDX: 0000001b2e920000 RSI: 000000000000094a RDI: 0000000000000003
RBP: 0000000000000001 R08: 00000000c167e94a R09: 00000000c167e94e
R10: 00007ffcc0c0a4c0 R11: 0000000000000293 R12: 000000000076bf00
R13: 00000000007727d8 R14: 000000000008d8bf R15: 000000000076bf0c
Kernel Offset: disabled
Rebooting in 86400 seconds..