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BUG: KCSAN: data-race in ktime_get_with_offset / timekeeping_update_from_shadow

write to 0xffffffff895f6508 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:2074 [inline]
 __hrtimer_run_queues+0x1f8/0x510 kernel/time/hrtimer.c:2131
 hrtimer_interrupt+0x27b/0x860 kernel/time/hrtimer.c:2250
 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
 futex_private_hash_put+0x1e/0xe0 kernel/futex/core.c:149
 class_hbr_destructor kernel/futex/futex.h:258 [inline]
 futex_wait_setup+0x327/0x3e0 kernel/futex/waitwake.c:696
 __futex_wait+0xa9/0x260 kernel/futex/waitwake.c:717
 futex_wait+0x98/0x1c0 kernel/futex/waitwake.c:750
 do_futex+0x391/0x460 kernel/futex/syscalls.c:133
 __do_sys_futex kernel/futex/syscalls.c:210 [inline]
 __se_sys_futex+0x2f6/0x370 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

read to 0xffffffff895f6528 of 8 bytes by interrupt on cpu 0:
 timekeeping_cycles_to_ns kernel/time/timekeeping.c:477 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:482 [inline]
 ktime_get_with_offset+0x150/0x260 kernel/time/timekeeping.c:1048
 ktime_get_real include/linux/timekeeping.h:87 [inline]
 netif_receive_skb_list_internal+0x1b4/0x5e0 net/core/dev.c:6475
 gro_normal_list include/net/gro.h:523 [inline]
 gro_flush_normal include/net/gro.h:531 [inline]
 napi_complete_done+0x19c/0x3f0 net/core/dev.c:6866
 virtqueue_napi_complete drivers/net/virtio_net.c:740 [inline]
 virtnet_poll+0x1b16/0x1fb0 drivers/net/virtio_net.c:3027
 __napi_poll+0x61/0x300 net/core/dev.c:7798
 napi_poll net/core/dev.c:7861 [inline]
 net_rx_action+0x456/0x930 net/core/dev.c:8018
 handle_softirqs+0xcc/0x2a0 kernel/softirq.c:645
 __do_softirq kernel/softirq.c:679 [inline]
 invoke_softirq kernel/softirq.c:519 [inline]
 __irq_exit_rcu+0x44/0xe0 kernel/softirq.c:758
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x74/0x80 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
 preempt_schedule_irq+0x27/0x50 kernel/sched/core.c:7606
 raw_irqentry_exit_cond_resched+0x49/0x60 kernel/entry/common.c:145
 irqentry_exit_to_kernel_mode_preempt+0x2b/0x40 include/linux/irq-entry-common.h:468
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x7d/0x610 kernel/entry/common.c:167
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:665
 get_current arch/x86/include/asm/current.h:25 [inline]
 get_ctx kernel/kcsan/core.c:206 [inline]
 check_access kernel/kcsan/core.c:758 [inline]
 __tsan_unaligned_write2+0x115/0x190 kernel/kcsan/core.c:1031
 sk_alloc+0x45/0x3e0 net/core/sock.c:2310
 inet_create+0x3cb/0x790 net/ipv4/af_inet.c:333
 __sock_create+0x2e5/0x580 net/socket.c:1676
 sock_create_kern+0x38/0x50 net/socket.c:1752
 smc_create_clcsk net/smc/af_smc.c:3358 [inline]
 smc_create+0x3ea/0x480 net/smc/af_smc.c:3395
 __sock_create+0x2e5/0x580 net/socket.c:1676
 sock_create net/socket.c:1734 [inline]
 __sys_socket_create net/socket.c:1771 [inline]
 __sys_socket+0xaf/0x180 net/socket.c:1818
 __do_sys_socket net/socket.c:1832 [inline]
 __se_sys_socket net/socket.c:1830 [inline]
 __x64_sys_socket+0x3f/0x50 net/socket.c:1830
 x64_sys_call+0x246e/0x2550 arch/x86/include/generated/asm/syscalls_64.h:42
 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: 0x000a039ad8340096 -> 0x000a9c315863645c

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 25128 Comm: syz.3.6643 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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