diff --git a/kernel/head.S b/kernel/head.S
index 6363534d..99400130 100644
--- a/kernel/head.S
+++ b/kernel/head.S
@@ -4,74 +4,6 @@
 
 #include "common/asm.h"
 
-
-// 以下是来自 multiboot2 规范的定义
-//  How many bytes from the start of the file we search for the header.
-#define MULTIBOOT_SEARCH 32768
-#define MULTIBOOT_HEADER_ALIGN 8
-
-//  The magic field should contain this.
-#define MULTIBOOT2_HEADER_MAGIC 0xe85250d6
-
-//  This should be in %eax.
-#define MULTIBOOT2_BOOTLOADER_MAGIC 0x36d76289
-
-//  Alignment of multiboot modules.
-#define MULTIBOOT_MOD_ALIGN 0x00001000
-
-//  Alignment of the multiboot info structure.
-#define MULTIBOOT_INFO_ALIGN 0x00000008
-
-//  Flags set in the 'flags' member of the multiboot header.
-
-#define MULTIBOOT_TAG_ALIGN 8
-#define MULTIBOOT_TAG_TYPE_END 0
-#define MULTIBOOT_TAG_TYPE_CMDLINE 1
-#define MULTIBOOT_TAG_TYPE_BOOT_LOADER_NAME 2
-#define MULTIBOOT_TAG_TYPE_MODULE 3
-#define MULTIBOOT_TAG_TYPE_BASIC_MEMINFO 4
-#define MULTIBOOT_TAG_TYPE_BOOTDEV 5
-#define MULTIBOOT_TAG_TYPE_MMAP 6
-#define MULTIBOOT_TAG_TYPE_VBE 7
-#define MULTIBOOT_TAG_TYPE_FRAMEBUFFER 8
-#define MULTIBOOT_TAG_TYPE_ELF_SECTIONS 9
-#define MULTIBOOT_TAG_TYPE_APM 10
-#define MULTIBOOT_TAG_TYPE_EFI32 11
-#define MULTIBOOT_TAG_TYPE_EFI64 12
-#define MULTIBOOT_TAG_TYPE_SMBIOS 13
-#define MULTIBOOT_TAG_TYPE_ACPI_OLD 14
-#define MULTIBOOT_TAG_TYPE_ACPI_NEW 15
-#define MULTIBOOT_TAG_TYPE_NETWORK 16
-#define MULTIBOOT_TAG_TYPE_EFI_MMAP 17
-#define MULTIBOOT_TAG_TYPE_EFI_BS 18
-#define MULTIBOOT_TAG_TYPE_EFI32_IH 19
-#define MULTIBOOT_TAG_TYPE_EFI64_IH 20
-#define MULTIBOOT_TAG_TYPE_LOAD_BASE_ADDR 21
-
-#define MULTIBOOT_HEADER_TAG_END 0
-#define MULTIBOOT_HEADER_TAG_INFORMATION_REQUEST 1
-#define MULTIBOOT_HEADER_TAG_ADDRESS 2
-#define MULTIBOOT_HEADER_TAG_ENTRY_ADDRESS 3
-#define MULTIBOOT_HEADER_TAG_CONSOLE_FLAGS 4
-#define MULTIBOOT_HEADER_TAG_FRAMEBUFFER 5
-#define MULTIBOOT_HEADER_TAG_MODULE_ALIGN 6
-#define MULTIBOOT_HEADER_TAG_EFI_BS 7
-#define MULTIBOOT_HEADER_TAG_ENTRY_ADDRESS_EFI32 8
-#define MULTIBOOT_HEADER_TAG_ENTRY_ADDRESS_EFI64 9
-#define MULTIBOOT_HEADER_TAG_RELOCATABLE 10
-
-#define MULTIBOOT_ARCHITECTURE_I386 0
-#define MULTIBOOT_ARCHITECTURE_MIPS32 4
-#define MULTIBOOT_HEADER_TAG_OPTIONAL 1
-
-#define MULTIBOOT_LOAD_PREFERENCE_NONE 0
-#define MULTIBOOT_LOAD_PREFERENCE_LOW 1
-#define MULTIBOOT_LOAD_PREFERENCE_HIGH 2
-
-#define MULTIBOOT_CONSOLE_FLAGS_CONSOLE_REQUIRED 1
-#define MULTIBOOT_CONSOLE_FLAGS_EGA_TEXT_SUPPORTED 2
-
-
 // 以下是来自 multiboot2 规范的定义
 //  How many bytes from the start of the file we search for the header.
 #define MULTIBOOT_SEARCH 32768