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BUG: KCSAN: data-race in kick_pool / wq_worker_running

read-write to 0xffff888237c2a8e4 of 4 bytes by task 3410 on cpu 0:
 wq_worker_running+0x9b/0x120 kernel/workqueue.c:1434
 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x524/0xf40 kernel/locking/mutex.c:821
 __mutex_lock_slowpath+0xa/0x10 kernel/locking/mutex.c:1164
 mutex_lock+0x88/0x90 kernel/locking/mutex.c:319
 exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
 synchronize_rcu_expedited+0x18a/0x770 kernel/rcu/tree_exp.h:961
 synchronize_rcu+0x35/0x2e0 kernel/rcu/tree.c:3389
 srcu_readers_active_idx_check kernel/rcu/srcutree.c:539 [inline]
 try_check_zero+0x17a/0x260 kernel/rcu/srcutree.c:1154
 srcu_advance_state kernel/rcu/srcutree.c:1864 [inline]
 process_srcu+0x1ea/0xd90 kernel/rcu/srcutree.c:1973
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0x4d4/0x9a0 kernel/workqueue.c:3405
 worker_thread+0x569/0x750 kernel/workqueue.c:3486
 kthread+0x221/0x270 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 task 3399 on cpu 1:
 need_more_worker kernel/workqueue.c:952 [inline]
 kick_pool+0x49/0x2d0 kernel/workqueue.c:1274
 __queue_work+0x8e9/0xb90 kernel/workqueue.c:2402
 queue_work_on+0xa9/0x140 kernel/workqueue.c:2452
 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+0x9f1/0xcc0 drivers/net/wireguard/send.c:388
 wg_packet_consume_data_done drivers/net/wireguard/receive.c:348 [inline]
 wg_packet_rx_poll+0xe0a/0x1090 drivers/net/wireguard/receive.c:474
 __napi_poll+0x61/0x300 net/core/dev.c:7735
 napi_threaded_poll_loop+0x1e8/0x6c0 net/core/dev.c:7855
 napi_threaded_poll+0x193/0x240 net/core/dev.c:7910
 kthread+0x221/0x270 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

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3399 Comm: napi/wg1-0 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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