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BUG: KCSAN: data-race in __tmigr_cpu_activate / tmigr_handle_remote

write to 0xffff888237c205e4 of 1 bytes by task 0 on cpu 0:
 __tmigr_cpu_activate+0x55/0x1f0 kernel/time/timer_migration.c:682
 tmigr_cpu_activate+0x8a/0xc0 kernel/time/timer_migration.c:705
 timer_clear_idle+0x28/0x100 kernel/time/timer.c:2380
 tick_nohz_restart_sched_tick+0x22/0x110 kernel/time/tick-sched.c:1095
 tick_nohz_idle_update_tick kernel/time/tick-sched.c:1440 [inline]
 tick_nohz_idle_exit+0xfe/0x1d0 kernel/time/tick-sched.c:1483
 do_idle+0x1ee/0x230 kernel/sched/idle.c:345
 cpu_startup_entry+0x25/0x30 kernel/sched/idle.c:430
 rest_init+0xef/0xf0 init/main.c:737
 start_kernel+0x57c/0x5e0 init/main.c:1079
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
 x86_64_start_kernel+0x94/0xa0 arch/x86/kernel/head64.c:488
 common_startup_64+0x12c/0x137

read to 0xffff888237c205e4 of 1 bytes by interrupt on cpu 1:
 tmigr_next_groupevt kernel/time/timer_migration.c:569 [inline]
 tmigr_next_expired_groupevt kernel/time/timer_migration.c:593 [inline]
 tmigr_handle_remote_up kernel/time/timer_migration.c:1023 [inline]
 __walk_groups kernel/time/timer_migration.c:488 [inline]
 tmigr_handle_remote+0x26e/0x910 kernel/time/timer_migration.c:1091
 run_timer_softirq+0x5f/0x70 kernel/time/timer.c:2452
 __do_softirq+0xc8/0x285 kernel/softirq.c:554
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu kernel/softirq.c:633 [inline]
 irq_exit_rcu+0x3c/0x90 kernel/softirq.c:645
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0x73/0x80 arch/x86/kernel/apic/apic.c:1043
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 kcsan_setup_watchpoint+0x404/0x410 kernel/kcsan/core.c:705
 ext4_map_blocks+0xe7/0xf50 fs/ext4/inode.c:506
 ext4_readdir+0x5e0/0x1ad0 fs/ext4/dir.c:181
 iterate_dir+0x12c/0x310 fs/readdir.c:110
 __do_sys_getdents64 fs/readdir.c:409 [inline]
 __se_sys_getdents64+0x88/0x1a0 fs/readdir.c:394
 __x64_sys_getdents64+0x43/0x50 fs/readdir.c:394
 x64_sys_call+0x2997/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:218
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3923 Comm: syz-executor.2 Tainted: G        W          6.9.0-rc4-syzkaller-00031-g96fca68c4fbf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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