syzbot

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BUG: KCSAN: data-race in io_wq_activate_free_worker / io_wq_worker

write to 0xffff88811ce1cf04 of 4 bytes by task 29216 on cpu 0:
 io_wq_worker+0x81/0x730 io_uring/io-wq.c:634
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff88811ce1cf04 of 4 bytes by task 29202 on cpu 1:
 io_wq_get_acct io_uring/io-wq.c:168 [inline]
 io_wq_activate_free_worker+0xfa/0x250 io_uring/io-wq.c:285
 io_wq_enqueue+0x25e/0x440 io_uring/io-wq.c:947
 io_queue_iowq+0x1d6/0x320 io_uring/io_uring.c:523
 io_queue_sqe_fallback+0x87/0xe0 io_uring/io_uring.c:2143
 io_submit_sqe io_uring/io_uring.c:2372 [inline]
 io_submit_sqes+0xc4b/0x10a0 io_uring/io_uring.c:2492
 __do_sys_io_uring_enter io_uring/io_uring.c:3668 [inline]
 __se_sys_io_uring_enter+0x1d1/0x17f0 io_uring/io_uring.c:3603
 __x64_sys_io_uring_enter+0x78/0x90 io_uring/io_uring.c:3603
 x64_sys_call+0x263/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:427
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000c -> 0x0000000b

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 29202 Comm: syz-executor.2 Not tainted 6.9.0-syzkaller-01049-g8815da98e06a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
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