syzbot

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BUG: KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_exit

write to 0xffff888237d1defc of 1 bytes by task 0 on cpu 1:
 tick_nohz_idle_exit+0xac/0x2a0 kernel/time/tick-sched.c:1292
 do_idle+0x21d/0x250 kernel/sched/idle.c:319
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 secondary_startup_64_no_verify+0xb1/0xbb

read to 0xffff888237d1defc of 1 bytes by task 20176 on cpu 0:
 get_cpu_idle_time_us+0x6b/0x1f0
 get_idle_time fs/proc/stat.c:54 [inline]
 show_stat+0x8bf/0xdd0 fs/proc/stat.c:175
 seq_read_iter+0x2e1/0x930 fs/seq_file.c:230
 proc_reg_read_iter+0xd6/0x170 fs/proc/inode.c:296
 call_read_iter include/linux/fs.h:2156 [inline]
 io_iter_do_read fs/io_uring.c:3501 [inline]
 io_read fs/io_uring.c:3558 [inline]
 io_issue_sqe+0xbee/0x55e0 fs/io_uring.c:6671
 __io_queue_sqe+0x20/0x440 fs/io_uring.c:7018
 io_queue_sqe fs/io_uring.c:7060 [inline]
 io_submit_sqe+0x77a/0x47d3 fs/io_uring.c:7263
 io_submit_sqes+0x25d/0x670 fs/io_uring.c:7369
 __do_sys_io_uring_enter fs/io_uring.c:10072 [inline]
 __se_sys_io_uring_enter+0x212/0xb00 fs/io_uring.c:10014
 __x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:10014
 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: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20176 Comm: syz-executor.3 Tainted: G        W         5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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