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BUG: KCSAN: data-race in ktime_get_ts64 / timekeeping_update_from_shadow

write to 0xffffffff8963c948 of 320 bytes by interrupt on cpu 0:
 timekeeping_update_from_shadow+0x46e/0x4b0 kernel/time/timekeeping.c:869
 __timekeeping_advance+0xb36/0xcf0 kernel/time/timekeeping.c:2666
 timekeeping_advance kernel/time/timekeeping.c:2674 [inline]
 update_wall_time+0x21/0x50 kernel/time/timekeeping.c:2684
 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:2079 [inline]
 __hrtimer_run_queues+0x1f8/0x510 kernel/time/hrtimer.c:2136
 hrtimer_interrupt+0x27b/0x860 kernel/time/hrtimer.c:2255
 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
 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:123 [inline]
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline]
 _raw_spin_unlock_irqrestore+0x1a/0x30 kernel/locking/spinlock.c:221
 __unix_dgram_recvmsg+0x39c/0x8d0 net/unix/af_unix.c:2620
 unix_dgram_recvmsg+0x7e/0x90 net/unix/af_unix.c:2694
 sock_recvmsg_nosec+0xc2/0xf0 net/socket.c:1154
 ____sys_recvmsg+0x23f/0x250 net/socket.c:2931
 ___sys_recvmsg+0x156/0x3a0 net/socket.c:2978
 do_recvmmsg+0x1e4/0x540 net/socket.c:3073
 __sys_recvmmsg net/socket.c:3147 [inline]
 __do_sys_recvmmsg net/socket.c:3170 [inline]
 __se_sys_recvmmsg net/socket.c:3163 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3163
 x64_sys_call+0x77f/0x2550 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x116/0x380 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff8963c968 of 8 bytes by task 3289 on cpu 1:
 timekeeping_cycles_to_ns kernel/time/timekeeping.c:478 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:483 [inline]
 ktime_get_ts64+0x144/0x2e0 kernel/time/timekeeping.c:1150
 poll_select_finish+0x1e2/0x470 fs/select.c:313
 do_pselect fs/select.c:771 [inline]
 __do_sys_pselect6 fs/select.c:809 [inline]
 __se_sys_pselect6+0x253/0x2a0 fs/select.c:800
 __x64_sys_pselect6+0x78/0x90 fs/select.c:800
 x64_sys_call+0x1dfc/0x2550 arch/x86/include/generated/asm/syscalls_64.h:271
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x116/0x380 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0005d1e1327516a6 -> 0x00066a77b2a47a6c

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3289 Comm: syz-executor Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
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