X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=blobdiff_plain;f=UefiCpuPkg%2FLibrary%2FMpInitLib%2FDxeMpLib.c;h=e7ed21c6cd2d68268a6e5912724a2b3a791eaad5;hp=d2bcef53d695ea828c795a854fdce1b9c15620b8;hb=bc2288f59ba2d613643ba66a9638bcc8c7340ddb;hpb=20737c2fe6895b2ce291c90596365e9d0ac467b0

diff --git a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
index d2bcef53d6..e7ed21c6cd 100644
--- a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
@@ -113,6 +113,40 @@ GetWakeupBuffer (
   return (UINTN) StartAddress;
 }
 
+/**
+  Get available EfiBootServicesCode memory below 4GB by specified size.
+
+  This buffer is required to safely transfer AP from real address mode to
+  protected mode or long mode, due to the fact that the buffer returned by
+  GetWakeupBuffer() may be marked as non-executable.
+
+  @param[in] BufferSize   Wakeup transition buffer size.
+
+  @retval other   Return wakeup transition buffer address below 4GB.
+  @retval 0       Cannot find free memory below 4GB.
+**/
+UINTN
+GetModeTransitionBuffer (
+  IN UINTN                BufferSize
+  )
+{
+  EFI_STATUS              Status;
+  EFI_PHYSICAL_ADDRESS    StartAddress;
+
+  StartAddress = BASE_4GB - 1;
+  Status = gBS->AllocatePages (
+                  AllocateMaxAddress,
+                  EfiBootServicesCode,
+                  EFI_SIZE_TO_PAGES (BufferSize),
+                  &StartAddress
+                  );
+  if (EFI_ERROR (Status)) {
+    StartAddress = 0;
+  }
+
+  return (UINTN)StartAddress;
+}
+
 /**
   Checks APs status and updates APs status if needed.
 
@@ -354,9 +388,9 @@ InitMpGlobalData (
   // Allocating it in advance since memory services are not available in
   // Exit Boot Services callback function.
   //
-  ApSafeBufferSize  = CpuMpData->AddressMap.RelocateApLoopFuncSize;
-  ApSafeBufferSize += CpuMpData->CpuCount * AP_SAFE_STACK_SIZE;
-
+  ApSafeBufferSize  = EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (
+                        CpuMpData->AddressMap.RelocateApLoopFuncSize
+                        ));
   Address = BASE_4GB - 1;
   Status  = gBS->AllocatePages (
                    AllocateMaxAddress,
@@ -365,9 +399,39 @@ InitMpGlobalData (
                    &Address
                    );
   ASSERT_EFI_ERROR (Status);
+
   mReservedApLoopFunc = (VOID *) (UINTN) Address;
   ASSERT (mReservedApLoopFunc != NULL);
-  mReservedTopOfApStack = (UINTN) Address + EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (ApSafeBufferSize));
+
+  //
+  // Make sure that the buffer memory is executable if NX protection is enabled
+  // for EfiReservedMemoryType.
+  // 
+  // TODO: Check EFI_MEMORY_XP bit set or not once it's available in DXE GCD
+  //       service.
+  //
+  Status = gDS->GetMemorySpaceDescriptor (Address, &MemDesc);
+  if (!EFI_ERROR (Status)) {
+    gDS->SetMemorySpaceAttributes (
+           Address,
+           ApSafeBufferSize,
+           MemDesc.Attributes & (~EFI_MEMORY_XP)
+           );
+  }
+
+  ApSafeBufferSize = EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (
+                       CpuMpData->CpuCount * AP_SAFE_STACK_SIZE
+                       ));
+  Address = BASE_4GB - 1;
+  Status  = gBS->AllocatePages (
+                   AllocateMaxAddress,
+                   EfiReservedMemoryType,
+                   EFI_SIZE_TO_PAGES (ApSafeBufferSize),
+                   &Address
+                   );
+  ASSERT_EFI_ERROR (Status);
+
+  mReservedTopOfApStack = (UINTN) Address + ApSafeBufferSize;
   ASSERT ((mReservedTopOfApStack & (UINTN)(CPU_STACK_ALIGNMENT - 1)) == 0);
   CopyMem (
     mReservedApLoopFunc,