fix: interrupt handler

kernel/gdt.s

@@ -7,7 +7,7 @@ setup_gdt:
 	lgdt [gdt_ptr]
 	jmp 0x08:.flush_cs
 .flush_cs:
-	mov ax, 0x10
+	mov ax, 0x10 ; data segment
 	mov ds, ax
 	mov es, ax
 	mov fs, ax
@@ -23,20 +23,16 @@ gdt_ptr:
 
 gdt_entries:
 	;; null descriptor
-	dw 0x0 ; limit
-	dw 0x0 ; base (low)
-	db 0x0 ; base (mid)
-	db 0x0 ; access
-	db 0x0 ; granularity
-	db 0x0 ; base (high)
+	dd 0x0
+	dd 0x0
 
 	;; kernel mode code segment
-	dw 0xFFFF
-	dw 0x00
-	db 0x00
-	db 0x9A
-	db 0xCF
-	db 0x00
+	dw 0xFFFF ; Limit
+	dw 0x00   ; Base (low)
+	db 0x00   ; Base (mid)
+	db 0x9A   ; Access: 1 (P) 0 (DPL), 1 (S), 1010 (Type)
+	db 0xCF   ; Granularity: 1 (G), 1 (D/B), 0 (AVL), Limit
+	db 0x00   ; Base (high)
 
 	;; kernel mode data segment
 	dw 0xFFFF

kernel/head.s

@@ -40,13 +40,14 @@ entry:
 	extern setup_idt
 	call setup_idt
 
-	int3
-
 	;extern setup_paging
 	;call setup_paging
 
+	int3
+
 	LOG file
 
+	cli
 hang:
 	hlt
 	jmp hang

kernel/idt.s

@@ -3,32 +3,40 @@ section .text
 global setup_idt
 setup_idt:
 %assign i 0
+%rep 32
 extern isr %+ i
 	mov eax, isr %+ i
-	mov [idt_entries + i * 4], ax
-	shr eax, 16
-	mov word [idt_entries + i * 4 + 2], 0x8
-	mov byte [idt_entries + i * 4 + 5], 0x8E
-	mov [idt_entries + i * 4 + 6], ax
+	; offset (low)
+	mov word [idt_entries + (i * 8)], ax
+	; segment selector (kernel code)
+	mov word [idt_entries + (i * 8) + 2], 0x08
 
+	; zero (skip)
+	; attr:  1 (Present) 00 (DPL) 0 1 (D: 32bits) 110
+	mov byte [idt_entries + (i * 8) + 5], 0x8E
+
+	; offset (high)
+	shr eax, 16
+	mov word [idt_entries + (i * 8) + 6], ax
 %assign i i+1
-%rep 32
 %endrep
+
 	lidt [idt_ptr]
 	sti
 	ret
 
 section .data
-
+align 8
 idt_ptr:
-	dw 256 * 8
+	dw 255 * 8
 	dd idt_entries
 
+align 8
 idt_entries:
 	times 256 dd 0x00000000, 0x00000000
-	;; dw isr_low
-	;; dw kernel cs
+	;; dw offset (low)
+	;; dw segment selector
 	;; db zero
-	;; db attr
-	;; dw isr_high
+	;; db attr | P | DPL | 0 D 1 1 0 |
+	;; dw offset (high)
 .end:

kernel/isr.s

@@ -15,7 +15,6 @@ isr%1:
 global isr%1
 isr%1:
 	cli
-	push byte 1
 	push byte %1
 	jmp isr_handler
 %endmacro
@@ -69,6 +68,9 @@ isr_handler:
 
 	LOG msg_interrupt
 
+	extern pic_eoi
+	call pic_eoi
+
 	pop eax
 	mov ds, ax
 	mov es, ax

kernel/paging.s

@@ -4,7 +4,7 @@ section .data
 align 4096
 
 page_directory:
-	times 1024 dd 0x00000002
+	times 1024 dd 0x00000000
 
 section .text
 

kernel/pic.s

@@ -1,24 +1,37 @@
 [BITS 32]
+
+PIC1_CMD	equ 0x20
+PIC1_DATA	equ 0x21
+PIC2_CMD	equ 0xA0
+PIC2_DATA	equ 0xA1
+
 section .text
 
 global setup_pic
 setup_pic:
 	mov al, 0x11
-	out 0x20, al
-	out 0xA0, al
+	out PIC1_CMD, al
+	out PIC2_CMD, al
 	
 	mov al, 0x20
-	out 0x21, al
+	out PIC1_DATA, al
 	mov al, 0x28
-	out 0xA1, al
+	out PIC2_DATA, al
 
 	mov al, 4
-	out 0x21, al
+	out PIC1_DATA, al
 	mov al, 2
-	out 0xA1, al
+	out PIC2_DATA, al
 
 	; mask all
 	mov al, 0xFF
-	out 0x21, al
-	out 0xA1, al
+	out PIC1_DATA, al
+	out PIC2_DATA, al
+	ret
+
+global pic_eoi
+pic_eoi:
+	mov al, 0x20
+	out PIC2_CMD, al
+	out PIC1_CMD, al
 	ret

tools/create-iso

@@ -18,7 +18,7 @@ EOF
 gen_iso_file() {
 	mkdir -p "$2/boot/grub"
 	echo "$grub_config" > "$2/boot/grub/grub.cfg"
-	sha256sum "$2"/vmstupid > "$2/boot/hashfile"
+	sha256sum vmstupid > "$2/boot/hashfile"
 
 	grub-mkrescue -o $1 $2
 }