WARNING: ODEBUG bug in process_one_work

WARNING: ODEBUG bug in process_one_work

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    39bed42d Merge tag 'for-linus-hmm' of git://git.kernel.org..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11f498d9e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=2646535f8818ae25
dashboard link: https://syzkaller.appspot.com/bug?extid=9affe13ceff50439d1be
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+9affe13ceff50439d1be@syzkaller.appspotmail.com

------------[ cut here ]------------
ODEBUG: free active (active state 0) object type: timer_list hint: xprt_init_autodisconnect+0x0/0x160 net/sunrpc/xprt.c:1311
WARNING: CPU: 0 PID: 3067 at lib/debugobjects.c:485 debug_print_object+0x168/0x250 lib/debugobjects.c:485
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 3067 Comm: kworker/0:57 Not tainted 5.5.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events kfree_rcu_work
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:485
Code: dd c0 74 91 88 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b5 00 00 00 48 8b 14 dd c0 74 91 88 48 c7 c7 20 6a 91 88 e8 17 ed a3 fd <0f> 0b 83 05 93 05 02 07 01 48 83 c4 20 5b 41 5c 41 5d 41 5e 5d c3
RSP: 0018:ffffc90008c1fbe0 EFLAGS: 00010086
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815e9806 RDI: fffff52001183f6e
RBP: ffffc90008c1fc20 R08: ffff88809e54c000 R09: ffffed1015d045c9
R10: ffffed1015d045c8 R11: ffff8880ae822e43 R12: 0000000000000001
R13: ffffffff89bb6760 R14: ffffffff816474a0 R15: ffff8880a839b9a0
 __debug_check_no_obj_freed lib/debugobjects.c:967 [inline]
 debug_check_no_obj_freed+0x2d6/0x441 lib/debugobjects.c:998
 kfree+0xf8/0x2c0 mm/slab.c:3756
 kfree_rcu_work+0x145/0x230 kernel/rcu/tree.c:2761
 process_one_work+0xa05/0x17a0 kernel/workqueue.c:2264
 worker_thread+0x98/0xe40 kernel/workqueue.c:2410
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..


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