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@ -301,7 +301,7 @@ In the end of the `early_irq_init` function we return the return value of the `a
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return arch_early_irq_init();
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```
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This function defined in the [kernel/apic/vector.c](https://github.com/torvalds/linux/blob/master/kernel/apic/vector.c) and contains only one call of the `arch_early_ioapic_init` function from the [kernel/apic/io_apic.c](https://github.com/torvalds/linux/blob/master/kernel/apic/io_apic.c). As we can understand from the `arch_early_ioapic_init` function's name, this function makes early initialization of the [I/O APIC](https://en.wikipedia.org/wiki/Advanced_Programmable_Interrupt_Controller). First of all it make a check of the number of the legacy interrupts wit the call of the `nr_legacy_irqs` function. If we have no legacy interrupts with the [Intel 8259](https://en.wikipedia.org/wiki/Intel_8259) programmable interrupt controller we set `io_apic_irqs` to the `0xffffffffffffffff`:
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This function defined in the [kernel/apic/vector.c](https://github.com/torvalds/linux/blob/master/kernel/apic/vector.c) and contains only one call of the `arch_early_ioapic_init` function from the [kernel/apic/io_apic.c](https://github.com/torvalds/linux/blob/master/kernel/apic/io_apic.c). As we can understand from the `arch_early_ioapic_init` function's name, this function makes early initialization of the [I/O APIC](https://en.wikipedia.org/wiki/Advanced_Programmable_Interrupt_Controller). First of all it make a check of the number of the legacy interrupts with the call of the `nr_legacy_irqs` function. If we have no legacy interrupts with the [Intel 8259](https://en.wikipedia.org/wiki/Intel_8259) programmable interrupt controller we set `io_apic_irqs` to the `0xffffffffffffffff`:
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```C
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if (!nr_legacy_irqs())
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