[Patch v4 1/5] UefiCpuPkg/PiSmmCpuDxeSmm: Use GDT/IDT saved in Smram.

[Eric Dong <eric.dong@intel.com>]

Current implementation will copy GDT/IDT at SmmReadyToLock point
from ACPI NVS memory to Smram. Later at S3 resume phase, it restore
the memory saved in Smram to ACPI NVS. It can directly use GDT/IDT
saved in Smram instead of restore the original ACPI NVS memory.
This patch do this change.

V4 changes:
1. Remove global variables mGdtForAp/mIdtForAp/mMachineCheckHandlerForAp.

Test Done:
  Do the OS boot and S3 resume test.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
---
 UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c | 31 ++++++++++++++-----------------
 1 file changed, 14 insertions(+), 17 deletions(-)

diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c b/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c
index 0b8ef70359..abd8a5a07b 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c
@@ -66,9 +66,6 @@ ACPI_CPU_DATA                mAcpiCpuData;
 volatile UINT32              mNumberToFinish;
 MP_CPU_EXCHANGE_INFO         *mExchangeInfo;
 BOOLEAN                      mRestoreSmmConfigurationInS3 = FALSE;
-VOID                         *mGdtForAp = NULL;
-VOID                         *mIdtForAp = NULL;
-VOID                         *mMachineCheckHandlerForAp = NULL;
 MP_MSR_LOCK                  *mMsrSpinLocks = NULL;
 UINTN                        mMsrSpinLockCount;
 UINTN                        mMsrCount = 0;
@@ -448,13 +445,6 @@ PrepareApStartupVector (
   CopyMem ((VOID *) (UINTN) &mExchangeInfo->GdtrProfile, (VOID *) (UINTN) mAcpiCpuData.GdtrProfile, sizeof (IA32_DESCRIPTOR));
   CopyMem ((VOID *) (UINTN) &mExchangeInfo->IdtrProfile, (VOID *) (UINTN) mAcpiCpuData.IdtrProfile, sizeof (IA32_DESCRIPTOR));
 
-  //
-  // Copy AP's GDT, IDT and Machine Check handler from SMRAM to ACPI NVS memory
-  //
-  CopyMem ((VOID *) mExchangeInfo->GdtrProfile.Base, mGdtForAp, mExchangeInfo->GdtrProfile.Limit + 1);
-  CopyMem ((VOID *) mExchangeInfo->IdtrProfile.Base, mIdtForAp, mExchangeInfo->IdtrProfile.Limit + 1);
-  CopyMem ((VOID *)(UINTN) mAcpiCpuData.ApMachineCheckHandlerBase, mMachineCheckHandlerForAp, mAcpiCpuData.ApMachineCheckHandlerSize);
-
   mExchangeInfo->StackStart  = (VOID *) (UINTN) mAcpiCpuData.StackAddress;
   mExchangeInfo->StackSize   = mAcpiCpuData.StackSize;
   mExchangeInfo->BufferStart = (UINT32) StartupVector;
@@ -831,6 +821,9 @@ GetAcpiCpuData (
   ACPI_CPU_DATA              *AcpiCpuData;
   IA32_DESCRIPTOR            *Gdtr;
   IA32_DESCRIPTOR            *Idtr;
+  VOID                       *GdtForAp;
+  VOID                       *IdtForAp;
+  VOID                       *MachineCheckHandlerForAp;
 
   if (!mAcpiS3Enable) {
     return;
@@ -893,14 +886,18 @@ GetAcpiCpuData (
   Gdtr = (IA32_DESCRIPTOR *)(UINTN)mAcpiCpuData.GdtrProfile;
   Idtr = (IA32_DESCRIPTOR *)(UINTN)mAcpiCpuData.IdtrProfile;
 
-  mGdtForAp = AllocatePool ((Gdtr->Limit + 1) + (Idtr->Limit + 1) +  mAcpiCpuData.ApMachineCheckHandlerSize);
-  ASSERT (mGdtForAp != NULL);
-  mIdtForAp = (VOID *) ((UINTN)mGdtForAp + (Gdtr->Limit + 1));
-  mMachineCheckHandlerForAp = (VOID *) ((UINTN)mIdtForAp + (Idtr->Limit + 1));
+  GdtForAp = AllocatePool ((Gdtr->Limit + 1) + (Idtr->Limit + 1) +  mAcpiCpuData.ApMachineCheckHandlerSize);
+  ASSERT (GdtForAp != NULL);
+  IdtForAp = (VOID *) ((UINTN)GdtForAp + (Gdtr->Limit + 1));
+  MachineCheckHandlerForAp = (VOID *) ((UINTN)IdtForAp + (Idtr->Limit + 1));
+
+  CopyMem (GdtForAp, (VOID *)Gdtr->Base, Gdtr->Limit + 1);
+  CopyMem (IdtForAp, (VOID *)Idtr->Base, Idtr->Limit + 1);
+  CopyMem (MachineCheckHandlerForAp, (VOID *)(UINTN)mAcpiCpuData.ApMachineCheckHandlerBase, mAcpiCpuData.ApMachineCheckHandlerSize);
 
-  CopyMem (mGdtForAp, (VOID *)Gdtr->Base, Gdtr->Limit + 1);
-  CopyMem (mIdtForAp, (VOID *)Idtr->Base, Idtr->Limit + 1);
-  CopyMem (mMachineCheckHandlerForAp, (VOID *)(UINTN)mAcpiCpuData.ApMachineCheckHandlerBase, mAcpiCpuData.ApMachineCheckHandlerSize);
+  Gdtr->Base = (UINTN)GdtForAp;
+  Idtr->Base = (UINTN)IdtForAp;
+  mAcpiCpuData.ApMachineCheckHandlerBase = (EFI_PHYSICAL_ADDRESS)(UINTN)MachineCheckHandlerForAp;
 }
 
 /**
-- 
2.15.0.windows.1