syzbot

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BUG: KCSAN: data-race in __io_free_req / __io_uring_files_cancel

write to 0xffff88813ac85a68 of 1 bytes by task 10874 on cpu 1:
 __io_uring_files_cancel+0x5c/0x1310 fs/io_uring.c:8678
 io_uring_files_cancel include/linux/io_uring.h:50 [inline]
 exit_files+0x6a/0xc0 fs/file.c:456
 do_exit+0x3ed/0x15a0 kernel/exit.c:801
 do_group_exit+0xc8/0x170 kernel/exit.c:903
 get_signal+0xf9b/0x1510 kernel/signal.c:2757
 arch_do_signal+0x25/0x260 arch/x86/kernel/signal.c:811
 exit_to_user_mode_loop kernel/entry/common.c:161 [inline]
 exit_to_user_mode_prepare+0xde/0x170 kernel/entry/common.c:191
 syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:266
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88813ac85a68 of 1 bytes by task 10878 on cpu 0:
 __io_free_req+0x7e/0x220 fs/io_uring.c:1841
 io_free_req fs/io_uring.c:2067 [inline]
 io_double_put_req fs/io_uring.c:2203 [inline]
 __io_req_task_cancel+0xc6/0x110 fs/io_uring.c:2004
 io_async_task_func+0x42b/0x650 fs/io_uring.c:5055
 task_work_run+0x8e/0x110 kernel/task_work.c:151
 io_wq_manager+0x15d/0x790 fs/io-wq.c:792
 kthread+0x1fa/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10878 Comm: io_wq_manager Not tainted 5.10.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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