loop4: detected capacity change from 0 to 2048
EXT4-fs (loop4): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
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BUG: KCSAN: data-race in print_cpu / tick_nohz_idle_enter

write to 0xffff888237d1b838 of 8 bytes by task 0 on cpu 1:
 tick_nohz_start_idle kernel/time/tick-sched.c:748 [inline]
 tick_nohz_idle_enter+0x89/0xe0 kernel/time/tick-sched.c:1264
 do_idle+0x3d/0x240 kernel/sched/idle.c:276
 cpu_startup_entry+0x25/0x30 kernel/sched/idle.c:428
 start_secondary+0x95/0xa0 arch/x86/kernel/smpboot.c:315
 common_startup_64+0x13e/0x147

read to 0xffff888237d1b838 of 8 bytes by task 24814 on cpu 0:
 print_cpu+0x502/0x680 kernel/time/timer_list.c:162
 timer_list_show+0x107/0x170 kernel/time/timer_list.c:295
 seq_read_iter+0x627/0x940 fs/seq_file.c:272
 proc_reg_read_iter+0x110/0x180 fs/proc/inode.c:299
 copy_splice_read+0x442/0x660 fs/splice.c:363
 do_splice_read fs/splice.c:982 [inline]
 splice_direct_to_actor+0x26f/0x680 fs/splice.c:1086
 do_splice_direct_actor fs/splice.c:1204 [inline]
 do_splice_direct+0xda/0x150 fs/splice.c:1230
 do_sendfile+0x380/0x650 fs/read_write.c:1370
 __do_sys_sendfile64 fs/read_write.c:1431 [inline]
 __se_sys_sendfile64 fs/read_write.c:1417 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1417
 x64_sys_call+0x2bb0/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000060060186ad -> 0x0000006006075ad3

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 24814 Comm: syz.4.7684 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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