Kernel: Use a different kernel load address for x86_64

Co-authored-by: Gunnar Beutner <gbeutner@serenityos.org>

Kernel/CMakeLists.txt

@@ -356,9 +356,11 @@ endif()
 if ("${SERENITY_ARCH}" STREQUAL "x86_64")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mcmodel=large -fno-pic -mno-red-zone")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -faligned-new=8")
+    set(KERNEL_LINKER_SCRIPT ${CMAKE_CURRENT_SOURCE_DIR}/linker_amd64.ld)
 else()
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pie -fPIE")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -faligned-new=4")
+    set(KERNEL_LINKER_SCRIPT ${CMAKE_CURRENT_SOURCE_DIR}/linker_i386.ld)
 endif()
 
 # Kernel Undefined Behavior Sanitizer (KUBSAN)
@@ -394,8 +396,8 @@ endif()
 add_executable(Kernel ${SOURCES})
 add_dependencies(Kernel generate_EscapeSequenceStateMachine.h)
 
-target_link_options(Kernel PRIVATE LINKER:-T ${CMAKE_CURRENT_SOURCE_DIR}/linker.ld -nostdlib)
+target_link_options(Kernel PRIVATE LINKER:-T ${KERNEL_LINKER_SCRIPT} -nostdlib)
-set_target_properties(Kernel PROPERTIES LINK_DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/linker.ld)
+set_target_properties(Kernel PROPERTIES LINK_DEPENDS ${KERNEL_LINKER_SCRIPT})
 
 if (ENABLE_KERNEL_LTO)
     include(CheckIPOSupported)

Kernel/linker_amd64.ld

@@ -0,0 +1,90 @@
+ENTRY(init)
+
+KERNEL_VIRTUAL_BASE = 0x2000000000;
+
+PHDRS
+{
+  text PT_LOAD ;
+  data PT_LOAD ;
+  bss PT_LOAD ;
+  ksyms PT_LOAD ;
+}
+
+SECTIONS
+{
+    . = KERNEL_VIRTUAL_BASE + 0x00200000;
+
+    start_of_kernel_image = .;
+
+    .text ALIGN(4K) : AT (ADDR(.text) - KERNEL_VIRTUAL_BASE)
+    {
+        start_of_kernel_text = .;
+
+        start_of_safemem_text = .;
+        KEEP(*(.text.safemem))
+        end_of_safemem_text = .;
+        start_of_safemem_atomic_text = .;
+        KEEP(*(.text.safemem.atomic))
+        end_of_safemem_atomic_text = .;
+
+        *(.text*)
+    } :text
+
+    .unmap_after_init ALIGN(4K) : AT (ADDR(.unmap_after_init) - KERNEL_VIRTUAL_BASE)
+    {
+        start_of_unmap_after_init = .;
+        *(.unmap_after_init*);
+        end_of_unmap_after_init = .;
+
+        end_of_kernel_text = .;
+    } :text
+
+    .rodata ALIGN(4K) : AT (ADDR(.rodata) - KERNEL_VIRTUAL_BASE)
+    {
+        start_heap_ctors = .;
+        *libkernel_heap.a:*(.ctors)
+        end_heap_ctors = .;
+
+        start_ctors = .;
+        *(.ctors)
+        end_ctors = .;
+
+        *(.rodata*)
+    } :data
+
+    .data ALIGN(4K) : AT (ADDR(.data) - KERNEL_VIRTUAL_BASE)
+    {
+        start_of_kernel_data = .;
+        *(.data*)
+        end_of_kernel_data = .;
+    } :data
+
+    .ro_after_init ALIGN(4K) (NOLOAD) : AT(ADDR(.ro_after_init) - KERNEL_VIRTUAL_BASE)
+    {
+        start_of_ro_after_init = .;
+        *(.ro_after_init);
+        end_of_ro_after_init = .;
+    } :data
+
+    .bss ALIGN(4K) (NOLOAD) : AT (ADDR(.bss) - KERNEL_VIRTUAL_BASE)
+    {
+        start_of_kernel_bss = .;
+        *(page_tables)
+        *(COMMON)
+        *(.bss)
+        end_of_kernel_bss = .;
+
+        . = ALIGN(4K);
+        *(.heap)
+    } :bss
+
+
+    .ksyms ALIGN(4K) : AT (ADDR(.ksyms) - KERNEL_VIRTUAL_BASE)
+    {
+        start_of_kernel_ksyms = .;
+        *(.kernel_symbols)
+        end_of_kernel_ksyms = .;
+    } :ksyms
+
+    end_of_kernel_image = .;
+}

Kernel/linker_i386.ld

@@ -4,8 +4,6 @@ KERNEL_VIRTUAL_BASE = 0xc0000000;
 
 PHDRS
 {
-  boot_text PT_LOAD ;
-  boot_bss PT_LOAD ;
   text PT_LOAD ;
   data PT_LOAD ;
   bss PT_LOAD ;
@@ -14,23 +12,10 @@ PHDRS
 
 SECTIONS
 {
-    . = KERNEL_VIRTUAL_BASE + 0x00100000;
+    . = KERNEL_VIRTUAL_BASE + 0x00200000;
 
     start_of_kernel_image = .;
 
-    .boot_text ALIGN(4K) : AT (ADDR(.boot_text) - KERNEL_VIRTUAL_BASE)
-    {
-        KEEP(*(.boot_text))
-        KEEP(*(.multiboot))
-    } :boot_text
-
-    .boot_bss ALIGN(4K) (NOLOAD) : AT (ADDR(.boot_bss) - KERNEL_VIRTUAL_BASE)
-    {
-        KEEP(*(.page_tables))
-        KEEP(*(.stack))
-        *(.super_pages)
-    } :boot_bss
-
     .text ALIGN(4K) : AT (ADDR(.text) - KERNEL_VIRTUAL_BASE)
     {
         start_of_kernel_text = .;