https://android.googlesource.com/kernel/common/+/c5aceac71b68f388cb011a8dc395943c5b083519/arch/x86/kernel/apic/x2apic_uv_x.c
arch/x86/kernel/apic/x2apic_uv_x.c - kernel/common - Git at Google
https://support.microsoft.com/en-gb/topic/a-fix-is-available-for-three-issues-in-the-x2apic-mode-in-x64-based-versions-of-windows-server-2008-r2-60d1868d-d491-055b-958f-3e55af56a011
A fix is available for three issues in the x2APIC mode in x64-based versions of Windows Server 2008...
Fixes three issues in the x2APIC mode on a computer that is running an x64-based version of Windows Server 2008 R2.