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BUG: KCSAN: data-race in kick_pool / wq_worker_running

read-write to 0xffff888237d299a4 of 4 bytes by task 3378 on cpu 1:
 wq_worker_running+0x98/0x130 kernel/workqueue.c:1400
 schedule_timeout+0xbc/0x170 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_fib6_rt_add drivers/net/netdevsim/fib.c:693 [inline]
 nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:759 [inline]
 nsim_fib6_event drivers/net/netdevsim/fib.c:856 [inline]
 nsim_fib_event drivers/net/netdevsim/fib.c:889 [inline]
 nsim_fib_event_work+0x1ff4/0x2290 drivers/net/netdevsim/fib.c:1493
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4de/0xa20 kernel/workqueue.c:3319
 worker_thread+0x52c/0x710 kernel/workqueue.c:3400
 kthread+0x4b7/0x540 kernel/kthread.c:464
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237d299a4 of 4 bytes by interrupt on cpu 0:
 need_more_worker kernel/workqueue.c:934 [inline]
 kick_pool+0x4d/0x2c0 kernel/workqueue.c:1240
 __queue_work+0x8f8/0xbb0 kernel/workqueue.c:2342
 queue_work_on+0xdf/0x190 kernel/workqueue.c:2392
 wg_queue_enqueue_per_device_and_peer drivers/net/wireguard/queueing.h:176 [inline]
 wg_packet_consume_data drivers/net/wireguard/receive.c:526 [inline]
 wg_packet_receive+0xf62/0x1360 drivers/net/wireguard/receive.c:576
 wg_receive+0x4e/0x80 drivers/net/wireguard/socket.c:326
 udp_queue_rcv_one_skb+0xae8/0xb80 net/ipv4/udp.c:2385
 udp_queue_rcv_skb+0x1f8/0x2a0 net/ipv4/udp.c:2463
 udp_unicast_rcv_skb+0x1ce/0x200 net/ipv4/udp.c:2623
 __udp4_lib_rcv+0xb0f/0xfd0 net/ipv4/udp.c:2699
 udp_rcv+0x4f/0x60 net/ipv4/udp.c:2881
 ip_protocol_deliver_rcu+0x3fe/0x760 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x180/0x210 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ip_local_deliver+0x102/0x1e0 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:469 [inline]
 ip_rcv_finish+0x193/0x1b0 net/ipv4/ip_input.c:447
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ip_rcv+0x68/0x140 net/ipv4/ip_input.c:567
 __netif_receive_skb_one_core net/core/dev.c:5887 [inline]
 __netif_receive_skb+0x109/0x290 net/core/dev.c:6000
 process_backlog+0x22e/0x440 net/core/dev.c:6352
 __napi_poll+0x63/0x3c0 net/core/dev.c:7324
 napi_poll net/core/dev.c:7388 [inline]
 net_rx_action+0x3a3/0x800 net/core/dev.c:7510
 handle_softirqs+0xbf/0x280 kernel/softirq.c:579
 do_softirq+0x62/0xa0 kernel/softirq.c:480
 __local_bh_enable_ip+0x6e/0x70 kernel/softirq.c:407
 __raw_read_unlock_bh include/linux/rwlock_api_smp.h:257 [inline]
 _raw_read_unlock_bh+0x1b/0x20 kernel/locking/spinlock.c:284
 wg_socket_send_skb_to_peer+0x109/0x130 drivers/net/wireguard/socket.c:184
 wg_packet_create_data_done drivers/net/wireguard/send.c:251 [inline]
 wg_packet_tx_worker+0x127/0x360 drivers/net/wireguard/send.c:276
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4de/0xa20 kernel/workqueue.c:3319
 worker_thread+0x52c/0x710 kernel/workqueue.c:3400
 kthread+0x4b7/0x540 kernel/kthread.c:464
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3379 Comm: kworker/0:3 Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: wg-crypt-wg1 wg_packet_tx_worker
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