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BUG: KCSAN: data-race in kick_pool / wq_worker_running

read-write to 0xffff888237d29d64 of 4 bytes by task 3382 on cpu 1:
 wq_worker_running+0x95/0x120 kernel/workqueue.c:1404
 synchronize_rcu_expedited+0x611/0x790 kernel/rcu/tree_exp.h:972
 synchronize_rcu+0x45/0x320 kernel/rcu/tree.c:3352
 xfrm_state_gc_task+0x96/0x4a0 net/xfrm/xfrm_state.c:631
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3319
 worker_thread+0x582/0x770 kernel/workqueue.c:3400
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x11f/0x1b0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237d29d64 of 4 bytes by task 10506 on cpu 0:
 need_more_worker kernel/workqueue.c:938 [inline]
 kick_pool+0x49/0x2d0 kernel/workqueue.c:1244
 __queue_work+0x8cb/0xb50 kernel/workqueue.c:2340
 queue_work_on+0xd1/0x160 kernel/workqueue.c:2390
 queue_work include/linux/workqueue.h:669 [inline]
 schedule_work include/linux/workqueue.h:730 [inline]
 __xfrm_state_destroy net/xfrm/xfrm_state.c:805 [inline]
 xfrm_state_put include/net/xfrm.h:928 [inline]
 xfrm_state_flush+0x32a/0x440 net/xfrm/xfrm_state.c:942
 pfkey_flush+0xbf/0x190 net/key/af_key.c:1769
 pfkey_process net/key/af_key.c:2848 [inline]
 pfkey_sendmsg+0x718/0x900 net/key/af_key.c:3699
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x142/0x180 net/socket.c:729
 ____sys_sendmsg+0x31e/0x4e0 net/socket.c:2614
 ___sys_sendmsg+0x17b/0x1d0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2703
 x64_sys_call+0x191e/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 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: 0 UID: 0 PID: 10506 Comm: syz.0.2583 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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