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ODEBUG: free active (active state 0) object type: work_struct hint: io_ring_file_ref_switch+0x0/0xac0 fs/io_uring.c:5651
WARNING: CPU: 0 PID: 9887 at lib/debugobjects.c:481 debug_print_object+0x168/0x250 lib/debugobjects.c:481
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 9887 Comm: syz-executor.5 Not tainted 5.5.0-rc6-next-20200116-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+0x197/0x210 lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:221
 __warn.cold+0x2f/0x3e kernel/panic.c:582
 report_bug+0x289/0x300 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:176 [inline]
 fixup_bug arch/x86/kernel/traps.c:171 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:269
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:288
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:debug_print_object+0x168/0x250 lib/debugobjects.c:481
Code: dd 00 d4 91 88 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b5 00 00 00 48 8b 14 dd 00 d4 91 88 48 c7 c7 60 c9 91 88 e8 57 9c a1 fd <0f> 0b 83 05 e3 13 01 07 01 48 83 c4 20 5b 41 5c 41 5d 41 5e 5d c3
RSP: 0018:ffffc90001807ba0 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 00000000000139f2 RSI: ffffffff815eb7c6 RDI: fffff52000300f66
RBP: ffffc90001807be0 R08: ffff88804f76a2c0 R09: ffffed1015d045c9
R10: ffffed1015d045c8 R11: ffff8880ae822e43 R12: 0000000000000001
R13: ffffffff89b7e460 R14: ffffffff814c81f0 R15: ffff88808b79d658
 __debug_check_no_obj_freed lib/debugobjects.c:963 [inline]
 debug_check_no_obj_freed+0x2d4/0x43f lib/debugobjects.c:994
 kfree+0xf8/0x2c0 mm/slab.c:3756
 io_sqe_files_unregister+0x3b1/0x6c0 fs/io_uring.c:5095
 __io_uring_register+0x389/0x2970 fs/io_uring.c:6606
 __do_sys_io_uring_register fs/io_uring.c:6664 [inline]
 __se_sys_io_uring_register fs/io_uring.c:6646 [inline]
 __x64_sys_io_uring_register+0x1a1/0x570 fs/io_uring.c:6646
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45b399
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f418cbd4c78 EFLAGS: 00000246 ORIG_RAX: 00000000000001ab
RAX: ffffffffffffffda RBX: 00007f418cbd56d4 RCX: 000000000045b399
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000008
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000001fc R14: 00000000004d1498 R15: 000000000075bfd4
Kernel Offset: disabled
Rebooting in 86400 seconds..