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BUG: KCSAN: data-race in kick_pool / wq_worker_running

read-write to 0xffff888237c2a8e4 of 4 bytes by task 7589 on cpu 0:
 wq_worker_running+0x9b/0x120 kernel/workqueue.c:1434
 schedule_timeout+0xca/0x180 kernel/time/sleep_timeout.c:99
 schedule_timeout_uninterruptible kernel/time/sleep_timeout.c:158 [inline]
 msleep+0x4f/0x90 kernel/time/sleep_timeout.c:318
 nsim_fib4_rt_add drivers/net/netdevsim/fib.c:369 [inline]
 nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:432 [inline]
 nsim_fib4_event drivers/net/netdevsim/fib.c:464 [inline]
 nsim_fib_event+0x3e17/0x4d40 drivers/net/netdevsim/fib.c:884
 nsim_fib_event_work+0x13d/0x210 drivers/net/netdevsim/fib.c:1493
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0x4f0/0x9c0 kernel/workqueue.c:3397
 worker_thread+0x58a/0x780 kernel/workqueue.c:3478
 kthread+0x22a/0x280 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237c2a8e4 of 4 bytes by interrupt on cpu 1:
 need_more_worker kernel/workqueue.c:952 [inline]
 kick_pool+0x49/0x2d0 kernel/workqueue.c:1274
 __queue_work+0x8b9/0xb00 kernel/workqueue.c:2394
 queue_work_on+0xa9/0x140 kernel/workqueue.c:2444
 wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:171 [inline]
 wg_packet_create_data drivers/net/wireguard/send.c:320 [inline]
 wg_packet_send_staged_packets+0x88e/0xb40 drivers/net/wireguard/send.c:388
 wg_packet_send_keepalive+0xeb/0x100 drivers/net/wireguard/send.c:239
 wg_expired_send_persistent_keepalive+0x3c/0x50 drivers/net/wireguard/timers.c:144
 call_timer_fn+0x3b/0x240 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2374 [inline]
 __run_timer_base+0x415/0x5f0 kernel/time/timer.c:2386
 run_timer_base kernel/time/timer.c:2395 [inline]
 run_timer_softirq+0x31/0x70 kernel/time/timer.c:2405
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x42/0xd0 kernel/softirq.c:735
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0x74/0x80 arch/x86/kernel/apic/apic.c:1061
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 native_save_fl arch/x86/include/asm/irqflags.h:26 [inline]
 arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline]
 arch_local_irq_save arch/x86/include/asm/irqflags.h:127 [inline]
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:130 [inline]
 _raw_spin_lock_irqsave+0x20/0xb0 kernel/locking/spinlock.c:166
 __skb_try_recv_datagram+0xf7/0x320 net/core/datagram.c:264
 __unix_dgram_recvmsg+0x25a/0x870 net/unix/af_unix.c:2587
 unix_dgram_recvmsg+0x7e/0x90 net/unix/af_unix.c:2686
 sock_recvmsg_nosec+0xc2/0xf0 net/socket.c:1137
 ____sys_recvmsg+0x26f/0x280 net/socket.c:2916
 ___sys_recvmsg+0x11f/0x3b0 net/socket.c:2960
 do_recvmmsg+0x1ef/0x560 net/socket.c:3055
 __sys_recvmmsg net/socket.c:3129 [inline]
 __do_sys_recvmmsg net/socket.c:3152 [inline]
 __se_sys_recvmmsg net/socket.c:3145 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3145
 x64_sys_call+0x80f/0x3020 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 11926 Comm: syz.7.3005 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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