Ninja-based buildsystem now building a running kernel!

src/arch/x86_64/kernel.ld

@@ -27,7 +27,7 @@ SECTIONS
 		*(.note.*)
 	}
 
-	.bss ALIGN(0x1000) : {
+	.bss ALIGN(16) : {
 		__bss_start = .;
 		*(.bss)
 		__bss_end = .;

src/boot/loader.c

@@ -87,6 +87,8 @@ loader_load_elf(
 {
 	EFI_STATUS status;
 
+	con_debug(L"Opening kernel file %s\r\n", (CHAR16 *)kernel_name);
+
 	EFI_FILE_PROTOCOL *file = NULL;
 	status = root->Open(root, &file, (CHAR16 *)kernel_name, EFI_FILE_MODE_READ,
 						EFI_FILE_READ_ONLY | EFI_FILE_HIDDEN | EFI_FILE_SYSTEM);
@@ -107,6 +109,8 @@ loader_load_elf(
 	status = file->Read(file, &length, &header);
 	CHECK_EFI_STATUS_OR_RETURN(status, L"Reading ELF header");
 
+	con_debug(L"Read %u bytes of ELF header\r\n", length);
+
 	if (length < sizeof(struct elf_header))
 		CHECK_EFI_STATUS_OR_RETURN(EFI_LOAD_ERROR, L"Incomplete read of ELF header");
 
@@ -131,10 +135,14 @@ loader_load_elf(
 		header.machine != 0x3e)
 		CHECK_EFI_STATUS_OR_RETURN(EFI_LOAD_ERROR, L"ELF load error: wrong machine architecture");
 
+	con_debug(L"ELF is valid, entrypoint %lu\r\n", header.entrypoint);
+
 	data->kernel_entry = (void *)header.entrypoint;
 
 	struct elf_program_header prog_header;
 	for (int i = 0; i < header.ph_num; ++i) {
+		con_debug(L"Reading ELF program header %d\r\n", i);
+
 		status = file->SetPosition(file, header.ph_offset + i * header.ph_entsize);
 		CHECK_EFI_STATUS_OR_RETURN(status, L"Setting ELF file position");
 
@@ -156,6 +164,8 @@ loader_load_elf(
 
 	struct elf_section_header sec_header;
 	for (int i = 0; i < header.sh_num; ++i) {
+		con_debug(L"Reading ELF section header %d ", i);
+
 		status = file->SetPosition(file, header.sh_offset + i * header.sh_entsize);
 		CHECK_EFI_STATUS_OR_RETURN(status, L"Setting ELF file position");
 
@@ -163,11 +173,15 @@ loader_load_elf(
 		status = file->Read(file, &length, &sec_header);
 		CHECK_EFI_STATUS_OR_RETURN(status, L"Reading ELF section header");
 
-		if ((sec_header.flags & ELF_SHF_ALLOC) == 0) continue;
+		if ((sec_header.flags & ELF_SHF_ALLOC) == 0) {
+			con_debug(L"SHF_ALLOC section\r\n");
+			continue;
+		}
 
 		void *addr = (void *)(sec_header.addr - KERNEL_VIRT_ADDRESS);
 
 		if (sec_header.type == ELF_ST_PROGBITS) {
+			con_debug(L"PROGBITS section\r\n");
 			status = file->SetPosition(file, sec_header.offset);
 			CHECK_EFI_STATUS_OR_RETURN(status, L"Setting ELF file position");
 
@@ -175,7 +189,10 @@ loader_load_elf(
 			status = file->Read(file, &length, addr);
 			CHECK_EFI_STATUS_OR_RETURN(status, L"Reading file");
 		} else if (sec_header.type == ELF_ST_NOBITS) {
+			con_debug(L"NOBITS section\r\n");
 			bootsvc->SetMem(addr, sec_header.size, 0);
+		} else {
+			con_debug(L"other section\r\n");
 		}
 	}
 

src/boot/utility.h

@@ -32,3 +32,9 @@ const CHAR16 *util_error_message(EFI_STATUS status);
 			: "r"((uint64_t)s), "r"((uint64_t)d), "r"((uint64_t)__LINE__) \
 			: "rax", "rdx", "r8", "r9", "r10"); \
 	}
+
+#ifdef BOOTLOADER_DEBUG
+#define con_debug(...) con_printf(L"DEBUG: " __VA_ARGS__)
+#else
+#define con_debug(...)
+#endif

src/kernel/gdt.s

@@ -3,17 +3,17 @@ extern g_gdtr
 
 global idt_write
 idt_write:
-	lidt [g_idtr]
+	lidt [rel g_idtr]
 	ret
 
 global idt_load
 idt_load:
-	sidt [g_idtr]
+	sidt [rel g_idtr]
 	ret
 
 global gdt_write
 gdt_write:
-	lgdt [g_gdtr]
+	lgdt [rel g_gdtr]
 	mov ax, si ; second arg is data segment
 	mov ds, ax
 	mov es, ax
@@ -30,6 +30,6 @@ gdt_write:
 
 global gdt_load
 gdt_load:
-	sgdt [g_gdtr]
+	sgdt [rel g_gdtr]
 	ret