syzbot

==================================================================
BUG: KCSAN: data-race in __io_cqring_fill_event / io_wake_function

write to 0xffff88814de40400 of 4 bytes by task 8023 on cpu 0:
 io_get_cqe fs/io_uring.c:1397 [inline]
 __io_cqring_fill_event+0xfb/0x350 fs/io_uring.c:1576
 io_req_complete_post+0x54/0x6a0 fs/io_uring.c:1600
 io_issue_sqe+0x41b8/0x69f0 fs/io_uring.c:4284
 io_wq_submit_work+0x113/0x270 fs/io_uring.c:6307
 io_worker_handle_work+0x8cb/0xaf0 fs/io-wq.c:496
 io_wqe_worker+0x184/0x4b0 fs/io-wq.c:545
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

read to 0xffff88814de40400 of 4 bytes by task 7178 on cpu 1:
 __io_cqring_events fs/io_uring.c:1381 [inline]
 io_cqring_events fs/io_uring.c:2222 [inline]
 io_should_wake fs/io_uring.c:6990 [inline]
 io_wake_function+0x40/0x130 fs/io_uring.c:7004
 __wake_up_common+0xbc/0x130 kernel/sched/wait.c:108
 __wake_up_common_lock kernel/sched/wait.c:138 [inline]
 __wake_up+0x80/0xc0 kernel/sched/wait.c:157
 io_cqring_ev_posted+0x4c/0x220 fs/io_uring.c:1416
 io_req_complete_post+0x405/0x6a0 fs/io_uring.c:1626
 io_issue_sqe+0x41b8/0x69f0 fs/io_uring.c:4284
 io_wq_submit_work+0x113/0x270 fs/io_uring.c:6307
 io_worker_handle_work+0x8cb/0xaf0 fs/io-wq.c:496
 io_wqe_worker+0x184/0x4b0 fs/io-wq.c:545
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

value changed: 0x00000b79 -> 0x00000b7a

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7178 Comm: iou-wrk-6006 Tainted: G        W         5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================