1) apic_write_around(APIC_ID, boot_cpu_physical_apicid) places the APIC
value in the lower 8 bits of APIC_ID, when it should be in the upper 8. As
as result, it effectively forces the APIC id to always be 0 for the boot
CPU, which is fatal on SMP AMD boxes.

 Fix: don't do the write at all. The APIC_ID value should be right already.

2) phys_cpu_present_map = 1 means we always set bit 0, but later on
   in setup_local_APIC() we do
        if (!clustered_apic_mode &&
            !test_bit(GET_APIC_ID(apic_read(APIC_ID)), &phys_cpu_present_map))
                BUG();
and the bug is triggered if the APIC_ID is not zero.

 Fix: initialize 'phys_cpu_present_map' correctly.