[PATCH v5 6/6] x86/apic: Set up through-local-APIC on boot CPU if 'noapic' specified

Currently kdump kernel becomes very slow if 'noapic' is specified. Normal kernel won't. Kernel parameter 'noapic' is used to disable IO-APIC in system for testing or special purpose. Here the root cause is that in kdump kernel LAPIC is disabled since commit 522e664644 ("x86/apic: Disable I/O APIC

[PATCH v5 6/6] x86/apic: Set up through-local-APIC on boot CPU if 'noapic' specified

Currently kdump kernel becomes very slow if 'noapic' is specified. Normal kernel won't. Kernel parameter 'noapic' is used to disable IO-APIC in system for testing or special purpose. Here the root cause is that in kdump kernel LAPIC is disabled since commit 522e664644 ("x86/apic: Disable I/O APIC