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BUG: KCSAN: data-race in hrtimer_interrupt / print_cpu

read-write to 0xffff888237d1b254 of 4 bytes by interrupt on cpu 1:
 hrtimer_interrupt+0x70/0x460 kernel/time/hrtimer.c:1865
 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
 check_kcov_mode kernel/kcov.c:185 [inline]
 write_comp_data kernel/kcov.c:246 [inline]
 __sanitizer_cov_trace_const_cmp2+0x37/0x90 kernel/kcov.c:307
 ext4_fill_raw_inode+0xb23/0xdc0 fs/ext4/inode.c:4803
 ext4_do_update_inode fs/ext4/inode.c:5650 [inline]
 ext4_mark_iloc_dirty+0x31f/0xda0 fs/ext4/inode.c:6303
 __ext4_mark_inode_dirty+0x2e2/0x3f0 fs/ext4/inode.c:6509
 ext4_dirty_inode+0x92/0xc0 fs/ext4/inode.c:6538
 __mark_inode_dirty+0x162/0x750 fs/fs-writeback.c:2527
 generic_update_time fs/inode.c:2063 [inline]
 inode_update_time fs/inode.c:2076 [inline]
 __file_update_time fs/inode.c:2304 [inline]
 file_update_time+0x288/0x2b0 fs/inode.c:2334
 ext4_page_mkwrite+0x18c/0xb90 fs/ext4/inode.c:6704
 do_page_mkwrite mm/memory.c:3361 [inline]
 do_shared_fault mm/memory.c:5649 [inline]
 do_fault mm/memory.c:5711 [inline]
 do_pte_missing mm/memory.c:4234 [inline]
 handle_pte_fault mm/memory.c:6052 [inline]
 __handle_mm_fault mm/memory.c:6195 [inline]
 handle_mm_fault+0x15ce/0x2c20 mm/memory.c:6364
 do_user_addr_fault+0x636/0x1090 arch/x86/mm/fault.c:1336
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

read to 0xffff888237d1b254 of 4 bytes by task 24842 on cpu 0:
 print_cpu+0x359/0x680 kernel/time/timer_list.c:135
 timer_list_show+0x107/0x170 kernel/time/timer_list.c:295
 seq_read_iter+0x319/0x940 fs/seq_file.c:230
 proc_reg_read_iter+0x10d/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: 0x000a0fdb -> 0x000a0fdc

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 24842 Comm: syz.1.8120 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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