syzbot

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BUG: KCSAN: data-race in create_io_worker / io_wqe_wake_worker

write to 0xffff888024e1a050 of 4 bytes by task 5871 on cpu 0:
 create_io_worker+0x2cb/0x3a0 fs/io-wq.c:706
 io_wq_manager+0x37f/0x790 fs/io-wq.c:801
 kthread+0x1fd/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

read to 0xffff888024e1a050 of 4 bytes by task 5856 on cpu 1:
 io_wqe_wake_worker+0x163/0x220 fs/io-wq.c:307
 io_wqe_enqueue+0x2bb/0x330 fs/io-wq.c:906
 io_wq_enqueue+0x3a/0x40 fs/io-wq.c:913
 __io_queue_async_work fs/io_uring.c:1566 [inline]
 io_queue_async_work+0x10c/0x320 fs/io_uring.c:1576
 __io_queue_sqe+0x5d5/0x7a0 fs/io_uring.c:6500
 __io_req_task_submit fs/io_uring.c:2133 [inline]
 io_async_task_func+0x50a/0x6c0 fs/io_uring.c:5299
 task_work_run+0x8e/0x110 kernel/task_work.c:140
 tracehook_notify_signal include/linux/tracehook.h:212 [inline]
 handle_signal_work kernel/entry/common.c:145 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0xf8/0x1a0 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:302
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5856 Comm: syz-executor.2 Not tainted 5.11.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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