==================================================================
BUG: KCSAN: data-race in kick_pool / wq_worker_running

read-write to 0xffff888237d29d24 of 4 bytes by task 3379 on cpu 1:
 wq_worker_running+0x95/0x120 kernel/workqueue.c:1400
 synchronize_rcu_expedited+0x611/0x790 kernel/rcu/tree_exp.h:1013
 synchronize_rcu+0x45/0x320 kernel/rcu/tree.c:3319
 free_ipc+0x80/0x1d0 ipc/namespace.c:178
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3321
 worker_thread+0x582/0x770 kernel/workqueue.c:3402
 kthread+0x486/0x510 kernel/kthread.c:464
 ret_from_fork+0xdd/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237d29d24 of 4 bytes by task 3316 on cpu 0:
 need_more_worker kernel/workqueue.c:934 [inline]
 kick_pool+0x49/0x2d0 kernel/workqueue.c:1240
 __queue_work+0x8d6/0xb60 kernel/workqueue.c:2342
 queue_work_on+0xd1/0x160 kernel/workqueue.c:2392
 queue_work include/linux/workqueue.h:662 [inline]
 schedule_work include/linux/workqueue.h:723 [inline]
 put_ipc_ns+0x11a/0x1b0 ipc/namespace.c:207
 free_nsproxy+0x88/0x2a0 kernel/nsproxy.c:190
 put_nsproxy include/linux/nsproxy.h:118 [inline]
 switch_task_namespaces kernel/nsproxy.c:241 [inline]
 exit_task_namespaces+0x78/0xc0 kernel/nsproxy.c:246
 do_exit+0x47a/0x1590 kernel/exit.c:954
 do_group_exit+0x139/0x140 kernel/exit.c:1104
 __do_sys_exit_group kernel/exit.c:1115 [inline]
 __se_sys_exit_group kernel/exit.c:1113 [inline]
 __x64_sys_exit_group+0x1f/0x20 kernel/exit.c:1113
 x64_sys_call+0x2fa4/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:232
 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: 3316 Comm: syz-executor Not tainted 6.16.0-rc2-syzkaller-00278-g3f75bfff44be #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================