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load_kernel_elf:
mov eax, [kernel_elf]
cmp eax, [.elf]
jne .fail
mov r8, [kernel_elf+32] ; program header pos
add r8, kernel_elf
movzx rbx, word[kernel_elf+54] ; program header size
movzx rdx, word[kernel_elf+56] ; num of program headers
.header:
cmp rdx, 0
je .start
mov edi, [r8] ; type
cmp edi, 0
je .next
cmp edi, 1
je .load
cmp edi, 2
je .fail
cmp edi, 3
je .fail
jmp .next
.load:
; zero out the segment
mov al, 0
mov rdi, [r8+16]
mov rcx, [r8+40]
rep stosb
; load from file
mov rdi, [r8+16]
mov rsi, [r8+8]
add rsi, kernel_elf
mov rcx, [r8+32]
rep movsb
.next:
add r8, rbx
dec rdx
jmp .header
.start:
; more stack space
mov rsp, 0x80000
xor rbp, rbp
; ELF entry point
mov rax, [kernel_elf+24]
call rax
.fail:
cli
hlt
jmp $
.elf: db 0x7f, "ELF"
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