registers.
The handler is now called after the register value is updated in the virtual
APIC page. This will make it easier to handle APIC-write VM-exits with APIC
register virtualization turned on.
We can no longer rely on the value of 'icr_timer' on the APIC page
in the callout handler. With APIC register virtualization the value of
'icr_timer' will be updated by the processor in guest-context before an
APIC-write VM-exit.
Clear the 'delivery status' bit in the ICRLO register in the write handler.
With APIC register virtualization the write happens in guest-context and
we cannot prevent a (buggy) guest from setting this bit.
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