Fix infinity reboot and add CI autotest feature

.github/workflows/c-cpp.yml

@@ -14,8 +14,10 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - name: configure
-      run: sudo apt install gcc build-essential grub2-common qemu-system-x86 xorriso mtools
+      run: |
+        sudo apt update
+        sudo apt install gcc build-essential grub2-common qemu-system-x86 xorriso mtools
     - name: make
       run: make
     - name: run and test
-      run: make test
+      run: make clean && make && make test

Makefile

@@ -25,14 +25,15 @@ kernel/kernel.elf: $(OBJS)
 	as $(ASFLAGS) -o $@ $<
 
 serial.log: cis-os.iso
-	timeout 10s qemu-system-x86_64 -m 256 -cdrom $< -d guest_errors -serial file:$@ || true
+	timeout 10s qemu-system-x86_64 -nographic -m 256 -cdrom $< -d guest_errors -serial file:$@ --no-reboot -no-shutdown || true
 
 test: serial.log
 	cat $<
+	ls
 	grep -q '\[OK\]' $< && echo "Test passed." || (echo "Test failed." && exit 1)
 
 run: cis-os.iso
-	qemu-system-x86_64 -m 256 -cdrom $< -d guest_errors -serial file:serial.log
+	qemu-system-x86_64 -m 256 -cdrom $< -d guest_errors -serial file:serial.log --no-reboot -no-shutdown
 
 clean:
 	rm -rf isodir

kernel/arch/amd64/boot.s

@@ -1,65 +1,183 @@
 .section .multiboot
-.align 8
+.code32
+
+.extern bss_start
+.extern end
+.extern phys
 
-.long 0x1BADB002
-.long 0x00000003
-.long -(0x1BADB002 + 0x00000003)
+.set MULTIBOOT_MAGIC,              0x1BADB002
+.set MULTIBOOT_FLAG_PAGE_ALIGN,    1 << 0
+.set MULTIBOOT_FLAG_MEMORY_INFO,   1 << 1
+.set MULTIBOOT_FLAGS,              MULTIBOOT_FLAG_PAGE_ALIGN | MULTIBOOT_FLAG_MEMORY_INFO
+.set MULTIBOOT_CHECKSUM,           -(MULTIBOOT_MAGIC + MULTIBOOT_FLAGS)
 
-.section .bss
-.align 16
+.align 4
+multiboot_header:
+.long MULTIBOOT_MAGIC
+.long MULTIBOOT_FLAGS
+.long MULTIBOOT_CHECKSUM
+.long multiboot_header
+.long phys
+.long bss_start
+.long end
+.long _start
+
+.section .stack, "aw", @nobits
 stack_bottom:
-    .skip 1024 * 4
+    .skip 16384
+.global stack_top
 stack_top:
 
-.section .text
+.section .bootstrap
 .code32
+.align 4
+
+.extern paging_main
+.extern jmp_long
+.type jmp_long, @function
+
+.extern kernel_main64
+.type kernel_main64, @function
+
 .global _start
+.type _start, @function
 _start:
-    movl $0xFFFFFFFF, %esp
-
-    movl $0x80000000, %eax
-    cpuid
-    cmpl $0x80000001, %eax
-    jb no_long_mode
-    movl $0x80000001, %eax
-    cpuid
-    testl $0x20000000, %edx
-    jnz long_mode_supported
-no_long_mode:
-    hlt
-long_mode_supported:
-    # PAE
-    movl %cr4, %eax
-    orl $0x20, %eax
-    movl %eax, %cr4
+    movl %ebx, %ecx
+    addl $16, %ecx
+    mov %ecx, %esp
+    call _forward
+_forward:
+    popl %ecx
+    subl $_forward, %ecx
+
+    mov $stack_top, %esp
+    addl %ecx, %esp
+    and $-16, %esp
+
+    pushl $0
+    pushl %esp
+    pushl $0
+    pushl %eax
+    pushl $0
+    pushl %ebx
+
+    jmp jmp_long
+
+.align 4
+
+jmp_long:
+    mov $paging_main, %edi
+    addl %ecx, %edi
+    pushl %ecx
+
+    mov $0x1007, %eax
+    add %edi, %eax
+    mov %eax, (%edi)
+
+    add $0x1000, %edi
+    mov $0x1003, %eax
+    add %edi, %eax
+    mov %eax, (%edi)
+
+    add $0x1000, %edi
+
+    mov $0x87, %ebx
+    mov $32, %ecx
 
-    # GDT
-    call gdt64_install
+.set_entry:
+    mov %ebx, (%edi)
+    add $0x200000, %ebx
+    add $8, %edi
+    loop .set_entry
 
-    # IDT
-    call idt_install
+    mov $paging_main, %edi
+    popl %ecx
+    addl %ecx, %edi
+    pushl %ecx
+    mov %edi, %cr3
 
-    # AMD64
-    movl $0x101, %eax
-    movl %eax, %cr0
-    movl %cr0, %eax
-    orl $0x80000000, %eax
-    movl %eax, %cr0
+    mov %cr4, %eax
+    or $32, %eax
+    mov %eax, %cr4
 
-    ljmp $0x08, $enter_long_mode
+    mov $0xC0000080, %ecx
+    rdmsr
+    or $256, %eax
+    wrmsr
+
+    mov %cr0, %eax
+    or $0x80000000, %eax
+    mov %eax, %cr0
+
+    popl %ecx
+
+    lea (_lgdt+3)(%ecx), %eax
+    movl (%eax), %ebx
+    addl %ecx, %ebx
+    movl %ebx, (%eax)
+
+    lea (gdtr+2)(%ecx), %eax
+    movl (%eax), %ebx
+    addl %ecx, %ebx
+    movl %ebx, (%eax)
+
+    lea (_ljmp+1)(%ecx), %eax
+    movl (%eax), %ebx
+    addl %ecx, %ebx
+    movl %ebx, (%eax)
+
+    pushl $0
+    pushl %ecx
+
+_lgdt:
+    lgdt gdtr
+
+_ljmp:
+    ljmp $0x08, $amd64
+
+.align 8
+gdtr:
+    .word gdt_end - gdt_base
+    .quad gdt_base
+
+gdt_base:
+    .quad 0
+    .word 0
+    .word 0
+    .byte 0
+    .byte 0x9a
+    .byte 0x20
+    .byte 0
+    .word 0xffff
+    .word 0
+    .byte 0
+    .byte 0x92
+    .byte 0
+    .byte 0
+gdt_end:
 
 .code64
-enter_long_mode:
-    movw $0x10, %ax
+.align 8
+.section .bootstrap
+
+amd64:
+    cli
+    mov $0x10, %ax
     mov %ax, %ds
     mov %ax, %es
     mov %ax, %fs
     mov %ax, %gs
     mov %ax, %ss
+    finit
 
-    movq stack_top, %rsp
-
-    call kernel_main64
+    cli
+    pop %rcx
+    pop %rdi
+    pop %rsi
+    pop %rdx
+    callq kernel_main64
 
+halt:
     cli
     hlt
+    jmp halt

kernel/kernel.c

@@ -1,5 +1,7 @@
 #include <kstdint.h>
 
+uint64_t paging_main[3][512] __attribute__((aligned(4096))) = {0};
+
 static inline void outb(uint16_t port, uint8_t val) {
 	asm volatile("outb %0, %1" : : "a"(val), "Nd"(port));
 }
@@ -8,21 +10,10 @@ void hal_write_byte_manual(uint8_t byte) {
 	outb(0x3f8, byte);
 }
 
-void puts(char *str) {
-    char *video_memory = (char *)0xB8000;
-    uint16_t *v = (uint16_t *)video_memory;
-    int i = 0;
-    while(str[i]) {
-        v[i] = (str[i] << 8) | 0x0F;
-        i++;
-    }
-}
-
-void kernel_main64() {
+void kernel_main64(uint64_t *multiboot, uint32_t magic, void *esp, uint64_t base) {
     hal_write_byte_manual('[');
     hal_write_byte_manual('O');
     hal_write_byte_manual('K');
     hal_write_byte_manual(']');
-    puts("Hello, World from CIS! ");
     for(;;) {}
 }