use objdump -h build/kernel-x86.bin to show sections, linker scripts squishes relevant ones together

kernel-rs/Cargo.toml

@@ -8,3 +8,4 @@ crate-type = ["staticlib"]
 
 [dependencies]
 rlibc = "1.0"
+multiboot2 = "0.1.0"

kernel-rs/src/arch/x86/boot.asm

@@ -4,11 +4,10 @@ extern x86_start
 section .text
 bits 32
 start:
-	mov esp, head_stack
+	push ebx
-	mov edi, ebx
 
 	call check_multiboot
-	lgdt [GDTR.ptr]
+	lgdt [GDTR.ptr]					; load the new gdt
 	jmp GDTR.gdt_cs:x86_start
 
 error:
@@ -78,18 +77,11 @@ GDTR:
 	DW 0x0			; Limit ( bits 0 -15 )
 	DW 0x0			; Base ( bits 0 -15 )
 	DB 0x0			; Base ( bits 16 -23 )
-	DB 0xF2			; [ Access Flags: 0x9A=11110110b = (present)|(Privilege Ring 3=11b)|(1)|(data => 0)|(expand up => 1)|(readable)|(0) ]
+	DB 0x00			; [ Access Flags: 0x9A=11110110b = (present)|(Privilege Ring 3=11b)|(1)|(data => 0)|(expand up => 1)|(readable)|(0) ]
-	DB 0xCF			; [ Flags: C=1100b = (granularity)|(32bit)|(!64bit)|(0) ] / [ Limits: (bits 16-19): F=1111b ]
+	DB 0x00			; [ Flags: C=1100b = (granularity)|(32bit)|(!64bit)|(0) ] / [ Limits: (bits 16-19): F=1111b ]
 	DB 0x0			; Base ( bits 24 -31 )
 
 .gdt_bottom:
 .ptr:
-	DW .gdt_bottom - .gdt_top - 1
+	DW .gdt_bottom - .gdt_top - 1	; length of the structure minus 1
-	DD .gdt_top
+	DD .gdt_top						; pointer to top of gdt
-
-
-section .bss
-align 4
-stack_end:
-	resb 4096 * 4
-head_stack:

kernel-rs/src/arch/x86/linker.ld

@@ -13,11 +13,13 @@ SECTIONS {
 	. = 1M;
 	kernel_start = . ;
 	/* ensure that the multiboot header is at the beginning */
-	.boot : {KEEP(*(.multiboot_header))}
+	.multiboot_header : { KEEP(*(.multiboot_header)) }
-	.text : {*(.text)}
+	.text : { *(.text .text.*) }
-	/* .rodata BLOCK(4K) : ALIGN(4K) {*(.rodata)} */
+	.rodata : { *(.rodata .rodata.*) }
-	/* .data BLOCK(4K) : ALIGN(4K) {*(.data)} */
+	.data.rel.ro : { *(.data.rel.ro.local*) *(.data.rel.ro .data.rel.ro.*) }
+	.debug : { *(.debug_*) }
+
 /* load stack */
-	.bss : {*(.bss)}
+.bss : {*(.bss .bss.*)}
-	kernel_end = . ;
+/* kernel_end = . ; */
 }

kernel-rs/src/arch/x86/start.asm

@@ -4,18 +4,13 @@ extern kmain
 section .text
 bits 32
 x86_start:
-; we should clear register but it does not work, it's okay with 0x10 instead of 0
+	mov ax, 0x10	; 16 bytes (0x10) is where the offset for data section (gdt_ds)
-mov ax, 0x10
 	mov ss, ax
 	mov ds, ax
 	mov es, ax
 	mov fs, ax
 	mov gs, ax
 
-; PRINT OK
-; mov dword [0xb8000], 0x2f4b2f4f
-; hlt
-
 	call kmain
 
 ; if main return, loop forever ; that should NEVER append

kernel-rs/src/lib.rs

@@ -1,4 +1,4 @@
-//! project hosted at [https://github.com/jzck/kernel]
+//! project hosted at (https://github.com/jzck/kernel)
 
 #![no_std]
 #![feature(lang_items)]
@@ -7,10 +7,10 @@
 #![feature(asm)]                //needed by cpuio for inline asm
 
 extern crate rlibc;
+extern crate multiboot2;
 
-#[macro_use]
 /// 80x25 screen and simplistic terminal driver
-pub mod vga;
+#[macro_use] pub mod vga;
 /// kernel init and environment
 pub mod context;
 /// PS/2 detection and processing
@@ -24,24 +24,42 @@ use context::CONTEXT;
 use vga::{Color, ColorCode};
 
 #[no_mangle]
-pub extern fn kmain() -> ! {
+pub extern fn kmain(multiboot_information_address: usize) -> ! {
-    unsafe { CONTEXT.current_term().color_code = ColorCode::new(Color::White, Color::Cyan); }
+    // unsafe { CONTEXT.current_term().color_code = ColorCode::new(Color::White, Color::Cyan); }
-    print!("{}{}{}{}{}{}{}{}{}{}{}{}{}{}",
+    // print!("{}{}{}{}{}{}{}{}{}{}{}{}{}{}",
-    format_args!("{: ^80}", r#"        ,--,               "#),
+    // format_args!("{: ^80}", r#"        ,--,               "#),
-    format_args!("{: ^80}", r#"      ,--.'|      ,----,   "#),
+    // format_args!("{: ^80}", r#"      ,--.'|      ,----,   "#),
-    format_args!("{: ^80}", r#"   ,--,  | :    .'   .' \  "#),
+    // format_args!("{: ^80}", r#"   ,--,  | :    .'   .' \  "#),
-    format_args!("{: ^80}", r#",---.'|  : '  ,----,'    | "#),
+    // format_args!("{: ^80}", r#",---.'|  : '  ,----,'    | "#),
-    format_args!("{: ^80}", r#";   : |  | ;  |    :  .  ; "#),
+    // format_args!("{: ^80}", r#";   : |  | ;  |    :  .  ; "#),
-    format_args!("{: ^80}", r#"|   | : _' |  ;    |.'  /  "#),
+    // format_args!("{: ^80}", r#"|   | : _' |  ;    |.'  /  "#),
-    format_args!("{: ^80}", r#":   : |.'  |  `----'/  ;   "#),
+    // format_args!("{: ^80}", r#":   : |.'  |  `----'/  ;   "#),
-    format_args!("{: ^80}", r#"|   ' '  ; :    /  ;  /    "#),
+    // format_args!("{: ^80}", r#"|   ' '  ; :    /  ;  /    "#),
-    format_args!("{: ^80}", r#"\   \  .'. |   ;  /  /-,   "#),
+    // format_args!("{: ^80}", r#"\   \  .'. |   ;  /  /-,   "#),
-    format_args!("{: ^80}", r#" `---`:  | '  /  /  /.`|   "#),
+    // format_args!("{: ^80}", r#" `---`:  | '  /  /  /.`|   "#),
-    format_args!("{: ^80}", r#"      '  ; |./__;      :   "#),
+    // format_args!("{: ^80}", r#"      '  ; |./__;      :   "#),
-    format_args!("{: ^80}", r#"      |  : ;|   :    .'    "#),
+    // format_args!("{: ^80}", r#"      |  : ;|   :    .'    "#),
-    format_args!("{: ^80}", r#"      '  ,/ ;   | .'       "#),
+    // format_args!("{: ^80}", r#"      '  ,/ ;   | .'       "#),
-    format_args!("{: ^80}", r#"      '--'  `---'          "#));
+    // format_args!("{: ^80}", r#"      '--'  `---'          "#));
-    unsafe { CONTEXT.current_term().color_code = ColorCode::new(Color::White, Color::Black); }
+    // unsafe { CONTEXT.current_term().color_code = ColorCode::new(Color::White, Color::Black); }
+    let boot_info = unsafe{ multiboot2::load(multiboot_information_address) };
+    let memory_map_tag = boot_info.memory_map_tag()
+        .expect("Memory map tag required");
+
+    println!("memory areas:");
+    for area in memory_map_tag.memory_areas() {
+        println!("    start: 0x{:x}, length: 0x{:x}",
+                 area.base_addr, area.length);
+    }
+
+    let elf_sections_tag = boot_info.elf_sections_tag()
+        .expect("Elf-sections tag required");
+
+    println!("kernel sections:");
+    for section in elf_sections_tag.sections() {
+        println!("    addr: 0x{:x}, size: 0x{:x}, flags: 0x{:x}",
+                 section.addr, section.size, section.flags);
+    }
     unsafe { CONTEXT.vga1.prompt();CONTEXT.vga1.flush(); }
     unsafe { CONTEXT.vga2.prompt(); }