diff options
| author | Gunnar Beutner <gbeutner@serenityos.org> | 2021-06-24 13:03:22 +0200 |
|---|---|---|
| committer | Andreas Kling <kling@serenityos.org> | 2021-06-25 15:19:09 +0200 |
| commit | d84abe51f569dd74637faadf5fb3f231189ff672 (patch) | |
| tree | 5fec24be89aeb56e6fd53f4eb3243dbef502ca81 /Kernel | |
| parent | 13e4093da4e94e2a5bb5576fa8d3faedaa78dd46 (diff) | |
| download | serenity-d84abe51f569dd74637faadf5fb3f231189ff672.zip | |
Kernel: Use PML4T for 64-bit mode
Diffstat (limited to 'Kernel')
| -rw-r--r-- | Kernel/Arch/x86/x86_64/Boot/boot.S | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/Kernel/Arch/x86/x86_64/Boot/boot.S b/Kernel/Arch/x86/x86_64/Boot/boot.S index 59920cf3aa..512562c203 100644 --- a/Kernel/Arch/x86/x86_64/Boot/boot.S +++ b/Kernel/Arch/x86/x86_64/Boot/boot.S @@ -10,6 +10,9 @@ kernel_cmdline: .section .page_tables, "aw", @nobits .align 4096 +.global boot_pml4t +boot_pml4t: +.skip 4096 .global boot_pdpt boot_pdpt: .skip 4096 @@ -41,7 +44,11 @@ boot_pd3_pt1023: .type multiboot_info_ptr, @object /* - construct the following (32-bit PAE) page table layout: + construct the following (64-bit PML4T) page table layout: + +pml4t: + + 0: pdpt (0-512GB) pdpt @@ -97,6 +104,18 @@ start: movl $(kernel_cmdline - 0xc0000000), %edi rep movsl + /* clear pml4t */ + movl $(boot_pml4t - 0xc0000000), %edi + movl $1024, %ecx + xorl %eax, %eax + rep stosl + + /* set up pml4t[0] */ + movl $(boot_pml4t - 0xc0000000), %edi + movl $(boot_pdpt - 0xc0000000), 0(%edi) + /* R/W + Present */ + orl $0x3, 0(%edi) + /* clear pdpt */ movl $(boot_pdpt - 0xc0000000), %edi movl $1024, %ecx @@ -105,8 +124,8 @@ start: /* set up pdpt[0] and pdpt[3] */ movl $(boot_pdpt - 0xc0000000), %edi - movl $((boot_pd0 - 0xc0000000) + 1), 0(%edi) - movl $((boot_pd3 - 0xc0000000) + 1), 24(%edi) + movl $((boot_pd0 - 0xc0000000) + 3), 0(%edi) + movl $((boot_pd3 - 0xc0000000) + 3), 24(%edi) /* clear pd0 */ movl $(boot_pd0 - 0xc0000000), %edi @@ -184,8 +203,8 @@ start: orl $0x3, 4088(%edi) movl $0, 4092(%edi) - /* point CR3 to PDPT */ - movl $(boot_pdpt - 0xc0000000), %eax + /* point CR3 to PML4T */ + movl $(boot_pml4t - 0xc0000000), %eax movl %eax, %cr3 /* enable PAE + PSE */ |