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BUG: KCSAN: data-race in kick_pool / wq_worker_running

read-write to 0xffff888237d29de4 of 4 bytes by task 4428 on cpu 1:
 wq_worker_running+0x95/0x120 kernel/workqueue.c:1406
 schedule_timeout+0xb7/0x170 kernel/time/sleep_timeout.c:99
 schedule_timeout_uninterruptible kernel/time/sleep_timeout.c:158 [inline]
 msleep+0x50/0x90 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 drivers/net/netdevsim/fib.c:884 [inline]
 nsim_fib_event_work+0x3b21/0x4790 drivers/net/netdevsim/fib.c:1493
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3346
 worker_thread+0x582/0x770 kernel/workqueue.c:3427
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x122/0x1b0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237d29de4 of 4 bytes by task 6313 on cpu 0:
 need_more_worker kernel/workqueue.c:940 [inline]
 kick_pool+0x49/0x2d0 kernel/workqueue.c:1246
 __queue_work+0x8cb/0xb50 kernel/workqueue.c:2342
 queue_work_on+0xd1/0x160 kernel/workqueue.c:2392
 schedule_work_on include/linux/workqueue.h:711 [inline]
 drain_all_stock+0x737/0x990 mm/memcontrol.c:2004
 try_charge_memcg+0x66e/0xa10 mm/memcontrol.c:2364
 obj_cgroup_charge_pages+0xa6/0x150 mm/memcontrol.c:2799
 __memcg_kmem_charge_page+0x9f/0x170 mm/memcontrol.c:2843
 __alloc_frozen_pages_noprof+0x188/0x360 mm/page_alloc.c:5195
 alloc_pages_mpol+0xb3/0x260 mm/mempolicy.c:2416
 alloc_frozen_pages_noprof mm/mempolicy.c:2487 [inline]
 alloc_pages_noprof+0x90/0x130 mm/mempolicy.c:2507
 vm_area_alloc_pages mm/vmalloc.c:3647 [inline]
 __vmalloc_area_node mm/vmalloc.c:3724 [inline]
 __vmalloc_node_range_noprof+0x7a5/0xed0 mm/vmalloc.c:3897
 __kvmalloc_node_noprof+0x483/0x670 mm/slub.c:7134
 ip_set_alloc+0x24/0x30 net/netfilter/ipset/ip_set_core.c:261
 hash_netiface_create+0x282/0x740 net/netfilter/ipset/ip_set_hash_gen.h:1568
 ip_set_create+0x3cc/0x970 net/netfilter/ipset/ip_set_core.c:1109
 nfnetlink_rcv_msg+0x4c6/0x590 net/netfilter/nfnetlink.c:302
 netlink_rcv_skb+0x123/0x220 net/netlink/af_netlink.c:2552
 nfnetlink_rcv+0x167/0x16c0 net/netfilter/nfnetlink.c:669
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x5c0/0x690 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x58b/0x6b0 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x145/0x180 net/socket.c:742
 ____sys_sendmsg+0x31e/0x4e0 net/socket.c:2630
 ___sys_sendmsg+0x17b/0x1d0 net/socket.c:2684
 __sys_sendmsg net/socket.c:2716 [inline]
 __do_sys_sendmsg net/socket.c:2721 [inline]
 __se_sys_sendmsg net/socket.c:2719 [inline]
 __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2719
 x64_sys_call+0x191e/0x3000 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: 6313 Comm: syz.9.623 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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