Hallo ihr Informatiker da drausen
Ich versuche gerade, angelehnt an das Tutorial von Tyndur die GDT zu laden, doch leider bisher ohne Erfolg (Der Rechner / Die VM bootet durch).
Ich habe das Problem soweit eingrenzen können, dass es sich in der Definition befinden müsste aber ich bin leider nicht in der Lage den Fehler zu eleminieren.
Hier der Code:
#include "init.h"
#include "os_look.h"
#include "stdio.h"
#include "stdint.h"
static int c_boot = 0x0e;
static int c_ok = 0x02;
static int c_bad = 0x04;
static int c_ct= 0x07;
void print_status(int status)
{
if(status==1)
{
set_color(c_ok);
printf("DONE\n");
}
else
{
set_color(c_bad);
printf("FAILED\n");
}
set_color(c_boot);
}
int start(void)
{
set_color(c_boot);
int status=0;
clear();
printf("Clearing Screen ");
print_status(1);
printf("Initializing Global Descriptor Tabel ");
print_status(init_gdt());
print_status(0);
status=0;
printf("Initializing Interrupt Descriptor Tabel ");
print_status(init_intr());
status=0;
printf("Printing OS Main Screen ");
print_status(print_look());
status=0;
set_color(c_ct);
return 0;
}
extern void intr_stub_0(void);
extern void intr_stub_1(void);
extern void intr_stub_2(void);
extern void intr_stub_3(void);
extern void intr_stub_4(void);
extern void intr_stub_5(void);
extern void intr_stub_6(void);
extern void intr_stub_7(void);
extern void intr_stub_8(void);
extern void intr_stub_9(void);
extern void intr_stub_10(void);
extern void intr_stub_11(void);
extern void intr_stub_12(void);
extern void intr_stub_13(void);
extern void intr_stub_14(void);
extern void intr_stub_15(void);
extern void intr_stub_16(void);
extern void intr_stub_17(void);
extern void intr_stub_18(void);
extern void intr_stub_32(void);
extern void intr_stub_33(void);
extern void intr_stub_48(void);
[COLOR="Red"]#define GDT_FLAG_DATASEG 0x02
#define GDT_FLAG_CODESEG 0x0a
#define GDT_FLAG_TSS 0x09
#define GDT_FLAG_SEGMENT 0x10
#define GDT_FLAG_RING0 0x00
#define GDT_FLAG_RING3 0x60
#define GDT_FLAG_PRESENT 0x80
#define GDT_FLAG_4K 0x800
#define GDT_FLAG_32_BIT 0x400
#define GDT_ENTRIES 5
static uint64_t gdt[GDT_ENTRIES];
#define IDT_ENTRIES 256
static long long unsigned int idt[IDT_ENTRIES];
static void gdt_set_entry(int i,unsigned int base,unsigned int limit,int flags)
{
gdt[i] = limit & 0xffffll;
gdt[i] |= (base & 0xffffffll) << 16;
gdt[i] |= (flags & 0xffll) << 40;
gdt[i] |= ((limit >> 16) & 0xfll) << 48;
gdt[i] |= ((flags >> 8) & 0xffll) << 52;
gdt[i] |= ((base >> 24) | 0xffll) << 56;
}
int init_gdt(void)
{
struct {
uint16_t limit;
void* pointer;
} __attribute__((packed)) gdtp = {.limit = GDT_ENTRIES * 8 - 1,.pointer = gdt,};
gdt_set_entry(0,0,0,0);
gdt_set_entry(1,0,0xfffff,GDT_FLAG_SEGMENT | GDT_FLAG_32_BIT | GDT_FLAG_CODESEG | GDT_FLAG_4K | GDT_FLAG_PRESENT);
gdt_set_entry(2,0,0xfffff,GDT_FLAG_SEGMENT | GDT_FLAG_32_BIT | GDT_FLAG_DATASEG | GDT_FLAG_4K | GDT_FLAG_PRESENT);
gdt_set_entry(3,0,0xfffff,GDT_FLAG_SEGMENT | GDT_FLAG_32_BIT | GDT_FLAG_CODESEG | GDT_FLAG_4K | GDT_FLAG_PRESENT | GDT_FLAG_RING3 );
gdt_set_entry(4,0,0xfffff,GDT_FLAG_SEGMENT | GDT_FLAG_32_BIT | GDT_FLAG_DATASEG | GDT_FLAG_4K | GDT_FLAG_PRESENT | GDT_FLAG_RING3 );[/COLOR]
[COLOR="Red"]asm volatile("lgdt %0" : : "m" (gdtp));[/COLOR]
asm volatile(
"mov $0x10, %ax;"
"mov %ax, %ds;"
"mov %ax, %es;"
"mov %ax, %ss;"
"ljmp $0x8, $.l;"
".l:"
);
return 1;
}
#define IDT_FLAG_INTERRUPT_GATE 0xe
#define IDT_FLAG_PRESENT 0x80
#define IDT_FLAG_RING0 0x00
#define IDT_FLAG_RING3 0x60
static void idt_set_entry(int i,void (*fn)(),unsigned int selector, int flags)
{
unsigned long int handler = (unsigned long int) fn;
idt[i] = handler & 0xffffLL;
idt[i] |= (selector & 0xffffLL) << 16;
idt[i] |= (flags & 0xffLL) << 40;
idt[i] |= ((handler>> 16) & 0xffffLL) <<48;
}
static inline void outb(uint16_t port, uint8_t data)
{
asm volatile("outb %0, %1" : : "a" (data), "Nd" (port));
}
static void init_pic(void)
{
outb(0x20, 0x11);
outb(0x21, 0x20);
outb(0x21, 0x04);
outb(0x21, 0x01);
outb(0xa0, 0x11);
outb(0xa1, 0x28);
outb(0xa1, 0x02);
outb(0xa1, 0x01);
outb(0x20, 0x0);
outb(0xa0, 0x0);
}
int init_intr(void)
{
struct
{
unsigned short int limit;
void* pointer;
}
__attribute__((packed)) idtp = { .limit = IDT_ENTRIES * 8 - 1, .pointer = idt,};
init_pic();
idt_set_entry(0, intr_stub_0, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(1, intr_stub_1, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(2, intr_stub_2, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(3, intr_stub_3, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(4, intr_stub_4, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(5, intr_stub_5, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(6, intr_stub_6, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(7, intr_stub_7, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(8, intr_stub_8, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(9, intr_stub_9, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(10, intr_stub_10, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(11, intr_stub_11, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(12, intr_stub_12, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(13, intr_stub_13, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(14, intr_stub_14, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(15, intr_stub_15, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(16, intr_stub_16, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(17, intr_stub_17, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(18, intr_stub_18, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(32, intr_stub_32, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(33, intr_stub_33, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING0 | IDT_FLAG_PRESENT);
idt_set_entry(48, intr_stub_48, 0x8, IDT_FLAG_INTERRUPT_GATE | IDT_FLAG_RING3 | IDT_FLAG_PRESENT);
asm volatile("lidt %0" : : "m" (idtp));
asm volatile("sti");
return 1;
}
void handle_interrupt(struct cpu_state* cpu)
{
if(cpu->intr <=0x1f)
{
printf("Exception %d, Kernel angehalten!\n", cpu->intr);
while(1)
{
asm volatile("cli; hlt");
}
}
else if(cpu->intr >=0x20 && cpu->intr <=0x2f)
{
if(cpu->intr >=0x28)
{
outb(0xa0,0x20);
}
outb(0x20,0x20);
}
else
{
printf("Unbekannter Interrupt\n");
while(1)
{
asm volatile("cli; hlt");
}
}
}
Zum Schluss noch das System:
SLES 11 Kernel 2.6 als VM
Compiler:
GCC 4.3.2
NASM 2.09rc1
Ich danke euch schonmal sehr und hoffe die Lösung liegt nicht ganz so fern :p
