Sync. x86bios with HEAD. - Detect illegal access to unmapped memory within real mode emulator. - Map EBDA if available and support memory wraparound above 1MB as VM86 does. - Set initial %ds to 0x40 as X.org int10 handler does. - Print the initial memory map when bootverbose is set. - Optimize real mode page table lookup. - Add strictly aligned memory access for distant future. - Update copyright date.