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BUG: KCSAN: data-race in ktime_get_with_offset / timekeeping_update_from_shadow

write to 0xffffffff893a5488 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
 mem_cgroup_lruvec include/linux/memcontrol.h:701 [inline]
 lruvec_stat_mod_folio+0x86/0x100 mm/memcontrol.c:992
 mod_lruvec_page_state include/linux/vmstat.h:528 [inline]
 vfree+0x13b/0x200 mm/vmalloc.c:3471
 cleanup_vm_area_work+0x55/0xb0 mm/vmalloc.c:3775
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0x4d4/0x9a0 kernel/workqueue.c:3397
 worker_thread+0x569/0x750 kernel/workqueue.c:3478
 kthread+0x221/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffffffff893a54a8 of 8 bytes by task 30119 on cpu 0:
 timekeeping_cycles_to_ns kernel/time/timekeeping.c:450 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:455 [inline]
 ktime_get_with_offset+0x150/0x260 kernel/time/timekeeping.c:1017
 ktime_get_real include/linux/timekeeping.h:88 [inline]
 netif_receive_skb_list_internal+0x1b4/0x5e0 net/core/dev.c:6412
 netif_receive_skb_list+0x33/0x1c0 net/core/dev.c:6487
 xdp_recv_frames net/bpf/test_run.c:268 [inline]
 xdp_test_run_batch net/bpf/test_run.c:349 [inline]
 bpf_test_run_xdp_live+0x1011/0x1330 net/bpf/test_run.c:378
 bpf_prog_test_run_xdp+0x559/0x9e0 net/bpf/test_run.c:1429
 bpf_prog_test_run+0x208/0x340 kernel/bpf/syscall.c:4742
 __sys_bpf+0x52e/0x7e0 kernel/bpf/syscall.c:6292
 __do_sys_bpf kernel/bpf/syscall.c:6387 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6385 [inline]
 __x64_sys_bpf+0x41/0x50 kernel/bpf/syscall.c:6385
 x64_sys_call+0x10cb/0x3020 arch/x86/include/generated/asm/syscalls_64.h:322
 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: 0x00185b34c02616b8 -> 0x0018f3cb40557a7e

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 30119 Comm: syz.5.7863 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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