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BUG: KCSAN: data-race in kick_pool / wq_worker_running

read-write to 0xffff888237c299a4 of 4 bytes by task 3379 on cpu 0:
 wq_worker_running+0x98/0x130 kernel/workqueue.c:1400
 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:6917
 __mutex_lock_common kernel/locking/mutex.c:678 [inline]
 __mutex_lock+0x420/0xa00 kernel/locking/mutex.c:746
 __mutex_lock_slowpath+0xa/0x10 kernel/locking/mutex.c:1033
 mutex_lock+0x2d/0x40 kernel/locking/mutex.c:277
 pcpu_balance_workfn+0x4a/0xab0 mm/percpu.c:2200
 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 0xffff888237c299a4 of 4 bytes by task 7285 on cpu 1:
 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
 queue_work include/linux/workqueue.h:662 [inline]
 schedule_work include/linux/workqueue.h:723 [inline]
 pcpu_schedule_balance_work mm/percpu.c:204 [inline]
 free_percpu+0x62a/0xb40 mm/percpu.c:2269
 xt_percpu_counter_free+0x63/0x80 net/netfilter/x_tables.c:1951
 cleanup_entry+0x19e/0x1d0 net/ipv6/netfilter/ip6_tables.c:671
 __do_replace+0x471/0x590 net/ipv6/netfilter/ip6_tables.c:1099
 do_replace net/ipv6/netfilter/ip6_tables.c:1158 [inline]
 do_ip6t_set_ctl+0x6f6/0x840 net/ipv6/netfilter/ip6_tables.c:1644
 nf_setsockopt+0x195/0x1b0 net/netfilter/nf_sockopt.c:101
 ipv6_setsockopt+0x10f/0x130 net/ipv6/ipv6_sockglue.c:998
 tcp_setsockopt+0x93/0xb0 net/ipv4/tcp.c:4077
 sock_common_setsockopt+0x64/0x80 net/core/sock.c:3894
 do_sock_setsockopt net/socket.c:2296 [inline]
 __sys_setsockopt+0x187/0x200 net/socket.c:2321
 __do_sys_setsockopt net/socket.c:2327 [inline]
 __se_sys_setsockopt net/socket.c:2324 [inline]
 __x64_sys_setsockopt+0x66/0x80 net/socket.c:2324
 x64_sys_call+0x2a09/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:55
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1a0 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: 7285 Comm: syz-executor Tainted: G        W           6.15.0-rc3-syzkaller-00001-g9d7a0577c9db #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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