BUG: spinlock bad magic on CPU#0, kworker/u4:2/29
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BUG: KASAN: global-out-of-bounds in task_pid_nr include/linux/sched.h:1240 [inline]
BUG: KASAN: global-out-of-bounds in spin_dump.cold+0xd7/0xe6 kernel/locking/spinlock_debug.c:65
Read of size 4 at addr ffffffff899bf2b0 by task kworker/u4:2/29

CPU: 0 PID: 29 Comm: kworker/u4:2 Not tainted 5.0.0+ #134
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x5/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131
 task_pid_nr include/linux/sched.h:1240 [inline]
 spin_dump.cold+0xd7/0xe6 kernel/locking/spinlock_debug.c:65
 spin_bug kernel/locking/spinlock_debug.c:75 [inline]
 debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline]
 do_raw_spin_lock+0x231/0x2e0 kernel/locking/spinlock_debug.c:112
 __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_lock+0x37/0x40 kernel/locking/spinlock.c:144
 spin_lock include/linux/spinlock.h:329 [inline]
 __queue_work+0x23d/0x1180 kernel/workqueue.c:1449
 queue_work_on+0x192/0x200 kernel/workqueue.c:1518
 queue_work include/linux/workqueue.h:494 [inline]
 rxrpc_destroy_all_client_connections+0x92/0xb8 net/rxrpc/conn_client.c:1161
 rxrpc_destroy_all_connections+0xa0/0x487 net/rxrpc/conn_object.c:468
 rxrpc_exit_net+0x1c2/0x310 net/rxrpc/net_ns.c:126
 ops_exit_list.isra.0+0xb0/0x160 net/core/net_namespace.c:153
 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:551
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x357/0x430 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

The buggy address belongs to the variable:
 wq_online+0x30/0x40

Memory state around the buggy address:
 ffffffff899bf180: 00 fa fa fa fa fa fa fa 01 fa fa fa fa fa fa fa
 ffffffff899bf200: 00 fa fa fa fa fa fa fa 01 fa fa fa fa fa fa fa
>ffffffff899bf280: 01 fa fa fa fa fa fa fa 01 fa fa fa fa fa fa fa
                                     ^
 ffffffff899bf300: 01 fa fa fa fa fa fa fa 00 fa fa fa fa fa fa fa
 ffffffff899bf380: 00 fa fa fa fa fa fa fa 00 00 fa fa fa fa fa fa
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