Charlie Jacobsen authored Jun 16, 2014 and Vikram Narayanan committed Oct 25, 2016

vmx_handle_external_intr
-- pretty much a straight copy over of the old code,
   but with comments
-- one big difference: interrupts are assumed to be
   enabled when this routine is called (I can't see
   how kvm is allowing the handling of external interrupts
   because it disables them when it enters vmx non-root.
   See the kvm code in x86.c:vcpu_enter_guest.)