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BUG: KCSAN: data-race in ktime_get / timekeeping_update_from_shadow

write to 0xffffffff893c34c8 of 304 bytes by interrupt on cpu 1:
 timekeeping_update_from_shadow+0x40d/0x440 kernel/time/timekeeping.c:835
 __timekeeping_advance+0xa68/0xc10 kernel/time/timekeeping.c:2613
 timekeeping_advance kernel/time/timekeeping.c:2621 [inline]
 update_wall_time+0x21/0x50 kernel/time/timekeeping.c:2631
 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:2032 [inline]
 __hrtimer_run_queues+0x1f8/0x510 kernel/time/hrtimer.c:2096
 hrtimer_interrupt+0x257/0x810 kernel/time/hrtimer.c:2215
 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+0x3e8/0x450 kernel/kcsan/core.c:705
 may_open+0x32/0x350 fs/namei.c:4240
 do_open fs/namei.c:4698 [inline]
 path_openat+0x1a43/0x2000 fs/namei.c:4859
 do_file_open+0x16c/0x290 fs/namei.c:4888
 do_sys_openat2+0xa0/0x130 fs/open.c:1395
 do_sys_open fs/open.c:1401 [inline]
 __do_sys_openat fs/open.c:1417 [inline]
 __se_sys_openat fs/open.c:1412 [inline]
 __x64_sys_openat+0xf2/0x120 fs/open.c:1412
 x64_sys_call+0x1e39/0x3020 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff893c34e8 of 8 bytes by task 8358 on cpu 0:
 timekeeping_cycles_to_ns kernel/time/timekeeping.c:450 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:455 [inline]
 ktime_get+0x130/0x240 kernel/time/timekeeping.c:973
 ktime_get_ns include/linux/timekeeping.h:175 [inline]
 copy_process+0x18fe/0x2350 kernel/fork.c:2427
 kernel_clone+0x1c0/0x5f0 kernel/fork.c:2745
 __do_sys_clone3 kernel/fork.c:3047 [inline]
 __se_sys_clone3+0x1f5/0x230 kernel/fork.c:3026
 __x64_sys_clone3+0x31/0x40 kernel/fork.c:3026
 x64_sys_call+0x580/0x3020 arch/x86/include/generated/asm/syscalls_64.h:436
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x000bd82711d9dd80 -> 0x000c70bd91e4c290

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 8358 Comm: syz.1.2209 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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