UefiCpuPkg/MpInitLib: put mReservedApLoopFunc in executable memory

[mirror_edk2.git] / UefiCpuPkg / Library / MpInitLib / DxeMpLib.c

diff --git a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
index d2bcef53d695ea828c795a854fdce1b9c15620b8..e7ed21c6cd2d68268a6e5912724a2b3a791eaad5 100644 (file)
--- a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
@@ -113,6 +113,40 @@ GetWakeupBuffer (
   return (UINTN) StartAddress;\r
 }\r
 \r
+/**\r
+  Get available EfiBootServicesCode memory below 4GB by specified size.\r
+\r
+  This buffer is required to safely transfer AP from real address mode to\r
+  protected mode or long mode, due to the fact that the buffer returned by\r
+  GetWakeupBuffer() may be marked as non-executable.\r
+\r
+  @param[in] BufferSize   Wakeup transition buffer size.\r
+\r
+  @retval other   Return wakeup transition buffer address below 4GB.\r
+  @retval 0       Cannot find free memory below 4GB.\r
+**/\r
+UINTN\r
+GetModeTransitionBuffer (\r
+  IN UINTN                BufferSize\r
+  )\r
+{\r
+  EFI_STATUS              Status;\r
+  EFI_PHYSICAL_ADDRESS    StartAddress;\r
+\r
+  StartAddress = BASE_4GB - 1;\r
+  Status = gBS->AllocatePages (\r
+                  AllocateMaxAddress,\r
+                  EfiBootServicesCode,\r
+                  EFI_SIZE_TO_PAGES (BufferSize),\r
+                  &StartAddress\r
+                  );\r
+  if (EFI_ERROR (Status)) {\r
+    StartAddress = 0;\r
+  }\r
+\r
+  return (UINTN)StartAddress;\r
+}\r
+\r
 /**\r
   Checks APs status and updates APs status if needed.\r
 \r
@@ -354,9 +388,9 @@ InitMpGlobalData (
   // Allocating it in advance since memory services are not available in\r
   // Exit Boot Services callback function.\r
   //\r
-  ApSafeBufferSize  = CpuMpData->AddressMap.RelocateApLoopFuncSize;\r
-  ApSafeBufferSize += CpuMpData->CpuCount * AP_SAFE_STACK_SIZE;\r
-\r
+  ApSafeBufferSize  = EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (\r
+                        CpuMpData->AddressMap.RelocateApLoopFuncSize\r
+                        ));\r
   Address = BASE_4GB - 1;\r
   Status  = gBS->AllocatePages (\r
                    AllocateMaxAddress,\r
@@ -365,9 +399,39 @@ InitMpGlobalData (
                    &Address\r
                    );\r
   ASSERT_EFI_ERROR (Status);\r
+\r
   mReservedApLoopFunc = (VOID *) (UINTN) Address;\r
   ASSERT (mReservedApLoopFunc != NULL);\r
-  mReservedTopOfApStack = (UINTN) Address + EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (ApSafeBufferSize));\r
+\r
+  //\r
+  // Make sure that the buffer memory is executable if NX protection is enabled\r
+  // for EfiReservedMemoryType.\r
+  // \r
+  // TODO: Check EFI_MEMORY_XP bit set or not once it's available in DXE GCD\r
+  //       service.\r
+  //\r
+  Status = gDS->GetMemorySpaceDescriptor (Address, &MemDesc);\r
+  if (!EFI_ERROR (Status)) {\r
+    gDS->SetMemorySpaceAttributes (\r
+           Address,\r
+           ApSafeBufferSize,\r
+           MemDesc.Attributes & (~EFI_MEMORY_XP)\r
+           );\r
+  }\r
+\r
+  ApSafeBufferSize = EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (\r
+                       CpuMpData->CpuCount * AP_SAFE_STACK_SIZE\r
+                       ));\r
+  Address = BASE_4GB - 1;\r
+  Status  = gBS->AllocatePages (\r
+                   AllocateMaxAddress,\r
+                   EfiReservedMemoryType,\r
+                   EFI_SIZE_TO_PAGES (ApSafeBufferSize),\r
+                   &Address\r
+                   );\r
+  ASSERT_EFI_ERROR (Status);\r
+\r
+  mReservedTopOfApStack = (UINTN) Address + ApSafeBufferSize;\r
   ASSERT ((mReservedTopOfApStack & (UINTN)(CPU_STACK_ALIGNMENT - 1)) == 0);\r
   CopyMem (\r
     mReservedApLoopFunc,\r