syzbot

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BUG: KCSAN: data-race in __io_cqring_fill_event / io_cqring_wait

write to 0xffff888106e15480 of 4 bytes by task 6421 on cpu 1:
 io_get_cqring fs/io_uring.c:1368 [inline]
 __io_cqring_fill_event+0xfd/0x350 fs/io_uring.c:1550
 io_submit_flush_completions+0xd2/0x3e0 fs/io_uring.c:2126
 __io_queue_sqe+0x1f9/0x360 fs/io_uring.c:6418
 io_queue_sqe fs/io_uring.c:6453 [inline]
 io_submit_sqe+0x18b7/0x33d0 fs/io_uring.c:6620
 io_submit_sqes+0x5bd/0xbd0 fs/io_uring.c:6728
 __do_sys_io_uring_enter fs/io_uring.c:9294 [inline]
 __se_sys_io_uring_enter+0x1e1/0xa80 fs/io_uring.c:9236
 __x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:9236
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888106e15480 of 4 bytes by task 6404 on cpu 0:
 __io_cqring_events fs/io_uring.c:1352 [inline]
 io_cqring_events fs/io_uring.c:2190 [inline]
 io_should_wake fs/io_uring.c:6933 [inline]
 io_cqring_wait_schedule fs/io_uring.c:6972 [inline]
 io_cqring_wait+0x522/0x860 fs/io_uring.c:7042
 __do_sys_io_uring_enter fs/io_uring.c:9320 [inline]
 __se_sys_io_uring_enter+0x621/0xa80 fs/io_uring.c:9236
 __x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:9236
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 6404 Comm: syz-executor.4 Not tainted 5.12.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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