diff options
Diffstat (limited to 'UefiCpuPkg/SecCore/SecMain.c')
| -rw-r--r-- | UefiCpuPkg/SecCore/SecMain.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/UefiCpuPkg/SecCore/SecMain.c b/UefiCpuPkg/SecCore/SecMain.c index 155be49a60..2416c4ce56 100644 --- a/UefiCpuPkg/SecCore/SecMain.c +++ b/UefiCpuPkg/SecCore/SecMain.c @@ -35,6 +35,43 @@ EFI_PEI_PPI_DESCRIPTOR mPeiSecPlatformInformationPpi[] = { }
};
+/**
+ Migrates the Global Descriptor Table (GDT) to permanent memory.
+
+ @retval EFI_SUCCESS The GDT was migrated successfully.
+ @retval EFI_OUT_OF_RESOURCES The GDT could not be migrated due to lack of available memory.
+
+**/
+EFI_STATUS
+MigrateGdt (
+ VOID
+ )
+{
+ EFI_STATUS Status;
+ UINTN GdtBufferSize;
+ IA32_DESCRIPTOR Gdtr;
+ VOID *GdtBuffer;
+
+ AsmReadGdtr ((IA32_DESCRIPTOR *) &Gdtr);
+ GdtBufferSize = sizeof (IA32_SEGMENT_DESCRIPTOR) -1 + Gdtr.Limit + 1;
+
+ Status = PeiServicesAllocatePool (
+ GdtBufferSize,
+ &GdtBuffer
+ );
+ ASSERT (GdtBuffer != NULL);
+ if (EFI_ERROR (Status)) {
+ return EFI_OUT_OF_RESOURCES;
+ }
+
+ GdtBuffer = ALIGN_POINTER (GdtBuffer, sizeof (IA32_SEGMENT_DESCRIPTOR));
+ CopyMem (GdtBuffer, (VOID *) Gdtr.Base, Gdtr.Limit + 1);
+ Gdtr.Base = (UINTN) GdtBuffer;
+ AsmWriteGdtr (&Gdtr);
+
+ return EFI_SUCCESS;
+}
+
//
// These are IDT entries pointing to 10:FFFFFFE4h.
//
@@ -410,6 +447,14 @@ SecTemporaryRamDone ( State = SaveAndDisableInterrupts ();
//
+ // Migrate GDT before NEM near down
+ //
+ if (PcdGetBool (PcdMigrateTemporaryRamFirmwareVolumes)) {
+ Status = MigrateGdt ();
+ ASSERT_EFI_ERROR (Status);
+ }
+
+ //
// Disable Temporary RAM after Stack and Heap have been migrated at this point.
//
SecPlatformDisableTemporaryMemory ();
|