X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=blobdiff_plain;f=UefiCpuPkg%2FLibrary%2FMpInitLib%2FDxeMpLib.c;h=e7ed21c6cd2d68268a6e5912724a2b3a791eaad5;hp=479f8189f6553f21347f5eef7b3f5823a0ae413b;hb=bc2288f59ba2d613643ba66a9638bcc8c7340ddb;hpb=a6b3d753f98118ee547ae935b347f4f00fa67e7c

diff --git a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
index 479f8189f6..e7ed21c6cd 100644
--- a/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/DxeMpLib.c
@@ -17,6 +17,7 @@
 #include <Library/UefiLib.h>
 #include <Library/UefiBootServicesTableLib.h>
 #include <Library/DebugAgentLib.h>
+#include <Library/DxeServicesTableLib.h>
 
 #include <Protocol/Timer.h>
 
@@ -112,6 +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.
 
@@ -288,9 +323,13 @@ InitMpGlobalData (
   IN CPU_MP_DATA               *CpuMpData
   )
 {
-  EFI_STATUS                 Status;
-  EFI_PHYSICAL_ADDRESS       Address;
-  UINTN                      ApSafeBufferSize;
+  EFI_STATUS                          Status;
+  EFI_PHYSICAL_ADDRESS                Address;
+  UINTN                               ApSafeBufferSize;
+  UINTN                               Index;
+  EFI_GCD_MEMORY_SPACE_DESCRIPTOR     MemDesc;
+  UINTN                               StackBase;
+  CPU_INFO_IN_HOB                     *CpuInfoInHob;
 
   SaveCpuMpData (CpuMpData);
 
@@ -301,6 +340,46 @@ InitMpGlobalData (
     return;
   }
 
+  if (PcdGetBool (PcdCpuStackGuard)) {
+    //
+    // One extra page at the bottom of the stack is needed for Guard page.
+    //
+    if (CpuMpData->CpuApStackSize <= EFI_PAGE_SIZE) {
+      DEBUG ((DEBUG_ERROR, "PcdCpuApStackSize is not big enough for Stack Guard!\n"));
+      ASSERT (FALSE);
+    }
+
+    //
+    // DXE will reuse stack allocated for APs at PEI phase if it's available.
+    // Let's check it here.
+    //
+    // Note: BSP's stack guard is set at DxeIpl phase. But for the sake of
+    // BSP/AP exchange, stack guard for ApTopOfStack of cpu 0 will still be
+    // set here.
+    //
+    CpuInfoInHob = (CPU_INFO_IN_HOB *)(UINTN)CpuMpData->CpuInfoInHob;
+    for (Index = 0; Index < CpuMpData->CpuCount; ++Index) {
+      if (CpuInfoInHob != NULL && CpuInfoInHob[Index].ApTopOfStack != 0) {
+        StackBase = (UINTN)CpuInfoInHob[Index].ApTopOfStack - CpuMpData->CpuApStackSize;
+      } else {
+        StackBase = CpuMpData->Buffer + Index * CpuMpData->CpuApStackSize;
+      }
+
+      Status = gDS->GetMemorySpaceDescriptor (StackBase, &MemDesc);
+      ASSERT_EFI_ERROR (Status);
+
+      Status = gDS->SetMemorySpaceAttributes (
+                      StackBase,
+                      EFI_PAGES_TO_SIZE (1),
+                      MemDesc.Attributes | EFI_MEMORY_RP
+                      );
+      ASSERT_EFI_ERROR (Status);
+
+      DEBUG ((DEBUG_INFO, "Stack Guard set at %lx [cpu%lu]!\n",
+              (UINT64)StackBase, (UINT64)Index));
+    }
+  }
+
   //
   // Avoid APs access invalid buffer data which allocated by BootServices,
   // so we will allocate reserved data for AP loop code. We also need to
@@ -309,9 +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,
@@ -320,9 +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,