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BUG: KCSAN: data-race in ktime_get / timekeeping_update_from_shadow

write to 0xffffffff895f1508 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+0x21/0x50 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
 __tsan_unaligned_write1+0x12/0x180 kernel/kcsan/core.c:1030
 iov_iter_init lib/iov_iter.c:179 [inline]
 __import_iovec+0x2c3/0x530 lib/iov_iter.c:1406
 import_iovec+0x60/0x80 lib/iov_iter.c:1440
 copy_msghdr_from_user net/socket.c:2650 [inline]
 recvmsg_copy_msghdr net/socket.c:2899 [inline]
 ___sys_recvmsg+0x385/0x3a0 net/socket.c:2971
 do_recvmmsg+0x1e5/0x560 net/socket.c:3070
 __sys_recvmmsg net/socket.c:3144 [inline]
 __do_sys_recvmmsg net/socket.c:3167 [inline]
 __se_sys_recvmmsg net/socket.c:3160 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3160
 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+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff895f1528 of 8 bytes by task 23049 on cpu 0:
 timekeeping_cycles_to_ns kernel/time/timekeeping.c:477 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:482 [inline]
 ktime_get+0x130/0x240 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: 0x0016eb1fce4eb694 -> 0x001783b64e7e1a5a

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 23049 Comm: syz.7.3775 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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EXT4-fs (loop7): unmounting filesystem 00000000-0000-0000-0000-000000000000.