MdeModulePkg/DxeIplPeim: reserve page 0 for NULL pointer detection

[mirror_edk2.git] / MdeModulePkg / Core / DxeIplPeim / X64 / DxeLoadFunc.c

/** @file\r
  x64-specifc functionality for DxeLoad.\r
\r
Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "DxeIpl.h"\r
#include "X64/VirtualMemory.h"\r
\r
\r
\r
/**\r
   Transfers control to DxeCore.\r
\r
   This function performs a CPU architecture specific operations to execute\r
   the entry point of DxeCore with the parameters of HobList.\r
   It also installs EFI_END_OF_PEI_PPI to signal the end of PEI phase.\r
\r
   @param DxeCoreEntryPoint         The entry point of DxeCore.\r
   @param HobList                   The start of HobList passed to DxeCore.\r
\r
**/\r
VOID\r
HandOffToDxeCore (\r
  IN EFI_PHYSICAL_ADDRESS   DxeCoreEntryPoint,\r
  IN EFI_PEI_HOB_POINTERS   HobList\r
  )\r
{\r
  VOID                            *BaseOfStack;\r
  VOID                            *TopOfStack;\r
  EFI_STATUS                      Status;\r
  UINTN                           PageTables;\r
  UINT32                          Index;\r
  EFI_VECTOR_HANDOFF_INFO         *VectorInfo;\r
  EFI_PEI_VECTOR_HANDOFF_INFO_PPI *VectorHandoffInfoPpi;\r
\r
  //\r
  // Clear page 0 and mark it as allocated if NULL pointer detection is enabled.\r
  //\r
  if (IsNullDetectionEnabled ()) {\r
    ClearFirst4KPage (HobList.Raw);\r
    BuildMemoryAllocationHob (0, EFI_PAGES_TO_SIZE (1), EfiBootServicesData);\r
  }\r
\r
  //\r
  // Get Vector Hand-off Info PPI and build Guided HOB\r
  //\r
  Status = PeiServicesLocatePpi (\r
             &gEfiVectorHandoffInfoPpiGuid,\r
             0,\r
             NULL,\r
             (VOID **)&VectorHandoffInfoPpi\r
             );\r
  if (Status == EFI_SUCCESS) {\r
    DEBUG ((EFI_D_INFO, "Vector Hand-off Info PPI is gotten, GUIDed HOB is created!\n"));\r
    VectorInfo = VectorHandoffInfoPpi->Info;\r
    Index = 1;\r
    while (VectorInfo->Attribute != EFI_VECTOR_HANDOFF_LAST_ENTRY) {\r
      VectorInfo ++;\r
      Index ++;\r
    }\r
    BuildGuidDataHob (\r
      &gEfiVectorHandoffInfoPpiGuid,\r
      VectorHandoffInfoPpi->Info,\r
      sizeof (EFI_VECTOR_HANDOFF_INFO) * Index\r
      );\r
  }\r
\r
  //\r
  // Allocate 128KB for the Stack\r
  //\r
  BaseOfStack = AllocatePages (EFI_SIZE_TO_PAGES (STACK_SIZE));\r
  ASSERT (BaseOfStack != NULL);\r
\r
  //\r
  // Compute the top of the stack we were allocated. Pre-allocate a UINTN\r
  // for safety.\r
  //\r
  TopOfStack = (VOID *) ((UINTN) BaseOfStack + EFI_SIZE_TO_PAGES (STACK_SIZE) * EFI_PAGE_SIZE - CPU_STACK_ALIGNMENT);\r
  TopOfStack = ALIGN_POINTER (TopOfStack, CPU_STACK_ALIGNMENT);\r
\r
  PageTables = 0;\r
  if (FeaturePcdGet (PcdDxeIplBuildPageTables)) {\r
    //\r
    // Create page table and save PageMapLevel4 to CR3\r
    //\r
    PageTables = CreateIdentityMappingPageTables ((EFI_PHYSICAL_ADDRESS) (UINTN) BaseOfStack, STACK_SIZE);\r
  } else {\r
    //\r
    // Set NX for stack feature also require PcdDxeIplBuildPageTables be TRUE\r
    // for the DxeIpl and the DxeCore are both X64.\r
    //\r
    ASSERT (PcdGetBool (PcdSetNxForStack) == FALSE);\r
    ASSERT (PcdGetBool (PcdCpuStackGuard) == FALSE);\r
  }\r
\r
  //\r
  // End of PEI phase signal\r
  //\r
  Status = PeiServicesInstallPpi (&gEndOfPeiSignalPpi);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  if (FeaturePcdGet (PcdDxeIplBuildPageTables)) {\r
    AsmWriteCr3 (PageTables);\r
  }\r
\r
  //\r
  // Update the contents of BSP stack HOB to reflect the real stack info passed to DxeCore.\r
  //\r
  UpdateStackHob ((EFI_PHYSICAL_ADDRESS)(UINTN) BaseOfStack, STACK_SIZE);\r
\r
  //\r
  // Transfer the control to the entry point of DxeCore.\r
  //\r
  SwitchStack (\r
    (SWITCH_STACK_ENTRY_POINT)(UINTN)DxeCoreEntryPoint,\r
    HobList.Raw,\r
    NULL,\r
    TopOfStack\r
    );\r
}\r