diff options
| author | etaIneLp <smallfry2006@yahoo.com> | 2020-05-25 17:58:49 -0400 |
|---|---|---|
| committer | Andreas Kling <kling@serenityos.org> | 2020-05-26 09:50:12 +0200 |
| commit | 82d0352a67830eaa710804e674713874444d8ba7 (patch) | |
| tree | 5aa7e433ae12390d6ca07d24f31d8bb22fe50cf4 /Kernel/Arch/i386/Boot | |
| parent | 826dc9418799d0488002a13448f5a48d62f31a31 (diff) | |
| download | serenity-82d0352a67830eaa710804e674713874444d8ba7.zip | |
Kernel: Unmap first MB after jumping above 3GB
Diffstat (limited to 'Kernel/Arch/i386/Boot')
| -rw-r--r-- | Kernel/Arch/i386/Boot/boot.S | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/Kernel/Arch/i386/Boot/boot.S b/Kernel/Arch/i386/Boot/boot.S index 9289cb5a5f..601a50a7ac 100644 --- a/Kernel/Arch/i386/Boot/boot.S +++ b/Kernel/Arch/i386/Boot/boot.S @@ -151,7 +151,6 @@ start: /* identity map the 0 to 2MB range */ movl $512, %ecx movl $(boot_pd0_pt0 - 0xc0000000), %edi - /*movl $0x100000, %eax*/ xorl %eax, %eax 1: @@ -203,6 +202,16 @@ start: movl %cr3, %eax movl %eax, %cr3 + /* unmap the 0-1MB range, which isn't used after jmp-ing up here */ + movl $256, %ecx + movl $(boot_pd0_pt0 - 0xc0000000), %edi + xorl %eax, %eax + +1: + movl %eax, 0(%edi) + addl $8, %edi + loop 1b + /* set up initial stack and jump into C++ land */ mov $stack_top, %esp and $-16, %esp |