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BUG: KCSAN: data-race in hrtimer_interrupt / print_cpu

write to 0xffff888237c1b260 of 8 bytes by interrupt on cpu 0:
 hrtimer_interrupt+0x193/0x460 kernel/time/hrtimer.c:1879
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x5c/0x1d0 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1050
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 kcsan_setup_watchpoint+0x415/0x430 kernel/kcsan/core.c:705
 file_inode include/linux/fs.h:1189 [inline]
 dnotify_flush+0x26/0x360 fs/notify/dnotify/dnotify.c:160
 filp_flush+0xb8/0x110 fs/open.c:1550
 filp_close+0x1d/0x40 fs/open.c:1560
 close_files fs/file.c:494 [inline]
 put_files_struct+0x11a/0x210 fs/file.c:509
 exit_files+0x65/0x80 fs/file.c:526
 do_exit+0x43d/0x15c0 kernel/exit.c:956
 do_group_exit+0xff/0x140 kernel/exit.c:1102
 get_signal+0xe59/0xf70 kernel/signal.c:3034
 arch_do_signal_or_restart+0x96/0x480 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x7a/0x100 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c1b260 of 8 bytes by task 8273 on cpu 1:
 print_cpu+0x30b/0x680 kernel/time/timer_list.c:133
 timer_list_show+0x107/0x170 kernel/time/timer_list.c:295
 seq_read_iter+0x62a/0x940 fs/seq_file.c:272
 proc_reg_read_iter+0x110/0x180 fs/proc/inode.c:299
 copy_splice_read+0x43f/0x660 fs/splice.c:363
 do_splice_read fs/splice.c:982 [inline]
 splice_direct_to_actor+0x26c/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: 0x00000019d6f2b2ab -> 0x00000019d784ff80

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 8273 Comm: syz.4.1646 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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