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BUG: KCSAN: data-race in hrtimer_interrupt / print_cpu

read-write to 0xffff888237c1ff54 of 4 bytes by interrupt on cpu 0:
 hrtimer_interrupt+0x72/0x7b0 kernel/time/hrtimer.c:1793
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline]
 __sysvec_apic_timer_interrupt+0x5c/0x1a0 arch/x86/kernel/apic/apic.c:1049
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1043
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 insert_header+0x6c3/0x930 fs/proc/proc_sysctl.c:245
 __register_sysctl_table+0xd38/0xdb0 fs/proc/proc_sysctl.c:1383
 register_net_sysctl_sz+0x199/0x1b0 net/sysctl_net.c:171
 neigh_sysctl_register+0x330/0x3a0 net/core/neighbour.c:3861
 addrconf_sysctl_register+0x86/0x130 net/ipv6/addrconf.c:7260
 ipv6_add_dev+0x8fb/0xab0 net/ipv6/addrconf.c:456
 addrconf_notify+0x407/0x950 net/ipv6/addrconf.c:3653
 notifier_call_chain kernel/notifier.c:93 [inline]
 raw_notifier_call_chain+0x6f/0x1d0 kernel/notifier.c:461
 call_netdevice_notifiers_info+0xae/0x100 net/core/dev.c:1994
 call_netdevice_notifiers_extack net/core/dev.c:2032 [inline]
 call_netdevice_notifiers net/core/dev.c:2046 [inline]
 register_netdevice+0xca9/0xe30 net/core/dev.c:10477
 tun_set_iff+0x5da/0x820 drivers/net/tun.c:2861
 __tun_chr_ioctl+0x652/0x1860 drivers/net/tun.c:3130
 tun_chr_ioctl+0x27/0x30 drivers/net/tun.c:3417
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xd3/0x150 fs/ioctl.c:893
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:893
 x64_sys_call+0x15cc/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c1ff54 of 4 bytes by task 5642 on cpu 1:
 print_cpu+0x348/0x670 kernel/time/timer_list.c:135
 timer_list_show+0x115/0x180 kernel/time/timer_list.c:295
 seq_read_iter+0x65b/0x940 fs/seq_file.c:272
 proc_reg_read_iter+0x11e/0x190 fs/proc/inode.c:299
 copy_splice_read+0x3a4/0x5d0 fs/splice.c:365
 do_splice_read fs/splice.c:985 [inline]
 splice_direct_to_actor+0x26c/0x670 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3ab/0x950 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 x64_sys_call+0xed5/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000cccb -> 0x0000ccce

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5642 Comm: syz.4.697 Not tainted 6.11.0-rc4-syzkaller-00033-g872cf28b8df9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
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