syzbot

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BUG: KCSAN: data-race in __io_fill_cqe / io_uring_poll

write to 0xffff888149ce8a00 of 4 bytes by task 7295 on cpu 0:
 io_get_cqe fs/io_uring.c:1725 [inline]
 __io_fill_cqe+0xf9/0x380 fs/io_uring.c:1915
 __io_req_complete_post+0x6c/0x420 fs/io_uring.c:1944
 io_req_complete_post fs/io_uring.c:1972 [inline]
 io_req_complete_failed fs/io_uring.c:2003 [inline]
 __io_queue_sqe+0x368/0x6a0 fs/io_uring.c:7115
 io_queue_sqe+0x46/0x550 fs/io_uring.c:7140
 io_submit_sqe+0x796/0x4b34 fs/io_uring.c:7348
 io_submit_sqes+0x25f/0x560 fs/io_uring.c:7454
 __do_sys_io_uring_enter fs/io_uring.c:10162 [inline]
 __se_sys_io_uring_enter+0x212/0xb00 fs/io_uring.c:10104
 __x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:10104
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888149ce8a00 of 4 bytes by task 7294 on cpu 1:
 __io_cqring_events fs/io_uring.c:1709 [inline]
 io_cqring_events fs/io_uring.c:2580 [inline]
 io_uring_poll+0xc6/0x146 fs/io_uring.c:9518
 vfs_poll include/linux/poll.h:88 [inline]
 ep_item_poll fs/eventpoll.c:853 [inline]
 ep_send_events fs/eventpoll.c:1692 [inline]
 ep_poll fs/eventpoll.c:1806 [inline]
 do_epoll_wait+0x6b7/0xf40 fs/eventpoll.c:2234
 __do_sys_epoll_wait fs/eventpoll.c:2246 [inline]
 __se_sys_epoll_wait fs/eventpoll.c:2241 [inline]
 __x64_sys_epoll_wait+0x119/0x140 fs/eventpoll.c:2241
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00001dd8 -> 0x00001df0

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7294 Comm: syz-executor.4 Not tainted 5.17.0-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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