.global loader                          # making entry point visible to linker

# setting up the Multiboot header - see GRUB docs for details
.set ALIGN,    1<<0                     # align loaded modules on page boundaries
.set MEMINFO,  1<<1                     # provide memory map
.set FLAGS,    ALIGN | MEMINFO          # this is the Multiboot 'flag' field
.set MAGIC,    0x1BADB002               # 'magic number' lets bootloader find the header
.set CHECKSUM, -(MAGIC + FLAGS)         # checksum required

.align 4
.long MAGIC
.long FLAGS
.long CHECKSUM

# reserve initial kernel stack space
.set STACKSIZE, 0x4000                  # that is, 16k.
.comm stack, STACKSIZE, 32              # reserve 16k stack on a quadword boundary

loader:
    mov   $(stack + STACKSIZE), %esp    # set up the stack
    push  %eax                          # Multiboot magic number
    push  %ebx                          # Multiboot data structure

    call kmain                          # call kernel proper

    cli
hang:
    hlt                                 # halt machine should kernel return
    jmp   hang