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BUG: KCSAN: data-race in ktime_get / timekeeping_update_from_shadow

write to 0xffffffff895ee508 of 320 bytes by interrupt on cpu 1:
 timekeeping_update_from_shadow+0x448/0x480 kernel/time/timekeeping.c:866
 __timekeeping_advance+0xb36/0xcf0 kernel/time/timekeeping.c:2663
 timekeeping_advance kernel/time/timekeeping.c:2671 [inline]
 update_wall_time+0x1d/0x50 kernel/time/timekeeping.c:2681
 tick_do_update_jiffies64+0x169/0x1c0 kernel/time/tick-sched.c:149
 tick_sched_do_timer kernel/time/tick-sched.c:253 [inline]
 tick_nohz_handler+0x88/0x380 kernel/time/tick-sched.c:310
 __run_hrtimer kernel/time/hrtimer.c:2067 [inline]
 __hrtimer_run_queues+0x1f8/0x510 kernel/time/hrtimer.c:2124
 hrtimer_interrupt+0x27b/0x860 kernel/time/hrtimer.c:2243
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1c0 arch/x86/kernel/apic/apic.c:1068
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
 kcsan_setup_watchpoint+0x42b/0x4a0 kernel/kcsan/core.c:713
 next_uptodate_folio+0x5e9/0x7f0 mm/filemap.c:3772
 filemap_map_pages+0xad3/0xf70 mm/filemap.c:3995
 do_fault_around mm/memory.c:5958 [inline]
 do_read_fault mm/memory.c:5991 [inline]
 do_fault mm/memory.c:6134 [inline]
 do_pte_missing mm/memory.c:4700 [inline]
 handle_pte_fault mm/memory.c:6558 [inline]
 __handle_mm_fault mm/memory.c:6707 [inline]
 handle_mm_fault+0x2166/0x3bb0 mm/memory.c:6876
 faultin_page mm/gup.c:1126 [inline]
 __get_user_pages+0x12e9/0x1eb0 mm/gup.c:1428
 populate_vma_page_range mm/gup.c:1860 [inline]
 __mm_populate+0x242/0x390 mm/gup.c:1963
 mm_populate include/linux/mm.h:4288 [inline]
 vm_mmap_pgoff+0x23b/0x2d0 mm/util.c:586
 ksys_mmap_pgoff+0xc1/0x310 mm/mmap.c:619
 x64_sys_call+0x23b3/0x2550 arch/x86/include/generated/asm/syscalls_64.h:10
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff895ee518 of 8 bytes by task 13219 on cpu 0:
 timekeeping_cycles_to_ns kernel/time/timekeeping.c:459 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:482 [inline]
 ktime_get+0xcf/0x240 kernel/time/timekeeping.c:1004
 futex_init_timeout kernel/futex/syscalls.c:185 [inline]
 __do_sys_futex kernel/futex/syscalls.c:204 [inline]
 __se_sys_futex+0x243/0x370 kernel/futex/syscalls.c:191
 __x64_sys_futex+0x78/0x90 kernel/futex/syscalls.c:191
 x64_sys_call+0x22e2/0x2550 arch/x86/include/generated/asm/syscalls_64.h:203
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000009d5bcdac98 -> 0x0000009d5d1d6547

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 13219 Comm: syz.6.2456 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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