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BUG: KCSAN: data-race in __queue_work / wq_worker_running

read-write to 0xffff888237d2abe0 of 4 bytes by task 3198 on cpu 1:
 wq_worker_running+0x96/0xe0 kernel/workqueue.c:880
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6741
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x38b/0x8c0 kernel/locking/mutex.c:747
 __mutex_lock_slowpath+0xa/0x10 kernel/locking/mutex.c:1035
 mutex_lock+0x23/0x30 kernel/locking/mutex.c:286
 rtnl_lock+0x11/0x20 net/core/rtnetlink.c:75
 addrconf_dad_work+0x4e/0xb80 net/ipv6/addrconf.c:4083
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

read to 0xffff888237d2abe0 of 4 bytes by task 3107 on cpu 0:
 __need_more_worker kernel/workqueue.c:785 [inline]
 insert_work kernel/workqueue.c:1365 [inline]
 __queue_work+0x79e/0xa60 kernel/workqueue.c:1517
 queue_work_on+0x7e/0xe0 kernel/workqueue.c:1545
 nsim_fib_event_nb+0xc2a/0xd70 drivers/net/netdevsim/fib.c:1043
 notifier_call_chain kernel/notifier.c:87 [inline]
 atomic_notifier_call_chain+0x63/0xd0 kernel/notifier.c:225
 call_fib_notifiers+0x62/0x90 net/core/fib_notifier.c:35
 call_fib6_notifiers+0x2e/0x40 net/ipv6/fib6_notifier.c:22
 call_fib6_entry_notifiers net/ipv6/ip6_fib.c:401 [inline]
 fib6_add_rt2node net/ipv6/ip6_fib.c:1223 [inline]
 fib6_add+0xeff/0x1fb0 net/ipv6/ip6_fib.c:1477
 __ip6_ins_rt net/ipv6/route.c:1302 [inline]
 ip6_ins_rt+0x74/0xb0 net/ipv6/route.c:1312
 __ipv6_ifa_notify+0x36f/0x8a0 net/ipv6/addrconf.c:6157
 ipv6_ifa_notify net/ipv6/addrconf.c:6196 [inline]
 addrconf_dad_completed+0xdd/0x8c0 net/ipv6/addrconf.c:4209
 addrconf_dad_work+0x85e/0xb80
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3107 Comm: kworker/0:2 Not tainted 6.2.0-rc5-syzkaller-00020-g7bf70dbb1882-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
Workqueue: ipv6_addrconf addrconf_dad_work
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