diff options
Diffstat (limited to 'UefiCpuPkg/CpuDxe/CpuGdt.c')
| -rw-r--r-- | UefiCpuPkg/CpuDxe/CpuGdt.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/UefiCpuPkg/CpuDxe/CpuGdt.c b/UefiCpuPkg/CpuDxe/CpuGdt.c index 8847bc4819..692402c55d 100644 --- a/UefiCpuPkg/CpuDxe/CpuGdt.c +++ b/UefiCpuPkg/CpuDxe/CpuGdt.c @@ -124,15 +124,26 @@ InitGlobalDescriptorTable ( VOID
)
{
+ EFI_STATUS Status;
GDT_ENTRIES *Gdt;
IA32_DESCRIPTOR Gdtr;
+ EFI_PHYSICAL_ADDRESS Memory;
//
- // Allocate Runtime Data for the GDT
- //
- Gdt = AllocateRuntimePool (sizeof (mGdtTemplate) + 8);
- ASSERT (Gdt != NULL);
- Gdt = ALIGN_POINTER (Gdt, 8);
+ // Allocate Runtime Data below 4GB for the GDT
+ // AP uses the same GDT when it's waken up from real mode so
+ // the GDT needs to be below 4GB.
+ //
+ Memory = SIZE_4GB - 1;
+ Status = gBS->AllocatePages (
+ AllocateMaxAddress,
+ EfiRuntimeServicesData,
+ EFI_SIZE_TO_PAGES (sizeof (mGdtTemplate)),
+ &Memory
+ );
+ ASSERT_EFI_ERROR (Status);
+ ASSERT ((Memory != 0) && (Memory < SIZE_4GB));
+ Gdt = (GDT_ENTRIES *) (UINTN) Memory;
//
// Initialize all GDT entries
|