start:
cli # BIOS enabled interrupts; disable
- # Set up the important data segment registers (DS, ES, SS).
- xorw %ax,%ax # Segment number zero
+ # Zero data segment registers DS, ES, and SS.
+ xorw %ax,%ax # Set %ax to zero
movw %ax,%ds # -> Data Segment
movw %ax,%es # -> Extra Segment
movw %ax,%ss # -> Stack Segment
outb %al,$0x60
# Switch from real to protected mode. Use a bootstrap GDT that makes
- # virtual addresses map dierctly to physical addresses so that the
+ # virtual addresses map directly to physical addresses so that the
# effective memory map doesn't change during the transition.
lgdt gdtdesc
movl %cr0, %eax