Merge tag 'x86-apic-2024-09-17' of git://git.kernel.org/pub/scm/linux/kernel/git...

Merge tag 'x86-apic-2024-09-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 APIC updates from Thomas Gleixner:

 - Handle an allocation failure in the IO/APIC code gracefully instead
   of crashing the machine.

 - Remove support for APIC local destination mode on 64bit

   Logical destination mode of the local APIC is used for systems with
   up to 8 CPUs. It has an advantage over physical destination mode as
   it allows to target multiple CPUs at once with IPIs. That advantage
   was definitely worth it when systems with up to 8 CPUs were state of
   the art for servers and workstations, but that's history.

   In the recent past there were quite some reports of new laptops
   failing to boot with logical destination mode, but they work fine
   with physical destination mode. That's not a suprise because physical
   destination mode is guaranteed to work as it's the only way to get a
   CPU up and running via the INIT/INIT/STARTUP sequence. Some of the
   affected systems were cured by BIOS updates, but not all OEMs provide
   them.

   As the number of CPUs keep increasing, logical destination mode
   becomes less used and the benefit for small systems, like laptops, is
   not really worth the trouble. So just remove logical destination mode
   support for 64bit and be done with it.

 - Code and comment cleanups in the APIC area.

* tag 'x86-apic-2024-09-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/irq: Fix comment on IRQ vector layout
  x86/apic: Remove unused extern declarations
  x86/apic: Remove logical destination mode for 64-bit
  x86/apic: Remove unused inline function apic_set_eoi_cb()
  x86/ioapic: Cleanup remaining coding style issues
  x86/ioapic: Cleanup line breaks
  x86/ioapic: Cleanup bracket usage
  x86/ioapic: Cleanup comments
  x86/ioapic: Move replace_pin_at_irq_node() to the call site
  iommu/vt-d: Cleanup apic_printk()
  x86/mpparse: Cleanup apic_printk()s
  x86/ioapic: Cleanup guarded debug printk()s
  x86/ioapic: Cleanup apic_printk()s
  x86/apic: Cleanup apic_printk()s
  x86/apic: Provide apic_printk() helpers
  x86/ioapic: Use guard() for locking where applicable
  x86/ioapic: Cleanup structs
  x86/ioapic: Mark mp_alloc_timer_irq() __init
  x86/ioapic: Handle allocation failures gracefully