syzbot

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BUG: KCSAN: data-race in get_cpu_idle_time_us / tick_nohz_idle_enter

write to 0xffff888237c1e0b4 of 1 bytes by task 0 on cpu 0:
 tick_nohz_idle_enter+0x72/0xc0 kernel/time/tick-sched.c:1113
 do_idle+0x3d/0x250 kernel/sched/idle.c:280
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 rest_init+0xfa/0x100 init/main.c:725
 arch_call_rest_init+0xa/0xb init/main.c:881
 start_kernel+0x5e4/0x669 init/main.c:1138
 secondary_startup_64_no_verify+0xc4/0xcb

read to 0xffff888237c1e0b4 of 1 bytes by task 15234 on cpu 1:
 get_cpu_idle_time_us+0x6b/0x1f0
 get_idle_time fs/proc/stat.c:54 [inline]
 show_stat+0x2ef/0xdd0 fs/proc/stat.c:134
 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:2068 [inline]
 io_iter_do_read fs/io_uring.c:3611 [inline]
 io_read fs/io_uring.c:3668 [inline]
 io_issue_sqe+0xb2e/0x98d0 fs/io_uring.c:6751
 __io_queue_sqe+0x20/0x6a0 fs/io_uring.c:7098
 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:10154 [inline]
 __se_sys_io_uring_enter+0x212/0xb00 fs/io_uring.c:10096
 __x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:10096
 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: 0x00 -> 0x05

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 15234 Comm: syz-executor.3 Tainted: G        W         5.17.0-rc2-syzkaller-00039-g9f7fb8de5d9b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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