StandaloneMmPkg/Core: remove legacy boot support

Remove the support for booting 'legacy' (i.e., non-UEFI boot) OSes.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: "Yao, Jiewen" <jiewen.yao@intel.com>
Reviewed-by: Achin Gupta <achin.gupta@arm.com>

2 files changed, 33 insertions, 113 deletions

diff --git a/StandaloneMmPkg/Core/StandaloneMmCore.c b/StandaloneMmPkg/Core/StandaloneMmCore.c
index 766cdb5c84..fb6b3055e9 100644
--- a/StandaloneMmPkg/Core/StandaloneMmCore.c
+++ b/StandaloneMmPkg/Core/StandaloneMmCore.c
@@ -88,20 +88,11 @@ EFI_MM_SYSTEM_TABLE  gMmCoreMmst = {
 };

 

 //

-// Flag to determine if the platform has performed a legacy boot.

-// If this flag is TRUE, then the runtime code and runtime data associated with the

-// MM IPL are converted to free memory, so the MM Core must guarantee that is

-// does not touch of the code/data associated with the MM IPL if this flag is TRUE.

-//

-BOOLEAN  mInLegacyBoot = FALSE;

-

-//

 // Table of MMI Handlers that are registered by the MM Core when it is initialized

 //

 MM_CORE_MMI_HANDLERS  mMmCoreMmiHandlers[] = {

   { MmReadyToLockHandler,    &gEfiDxeMmReadyToLockProtocolGuid,  NULL, TRUE  },

   { MmEndOfDxeHandler,       &gEfiEndOfDxeEventGroupGuid,        NULL, FALSE },

-  { MmLegacyBootHandler,     &gEfiEventLegacyBootGuid,           NULL, FALSE },

   { MmExitBootServiceHandler,&gEfiEventExitBootServicesGuid,     NULL, FALSE },

   { MmReadyToBootHandler,    &gEfiEventReadyToBootGuid,          NULL, FALSE },

   { NULL,                    NULL,                               NULL, FALSE },

@@ -143,47 +134,6 @@ MmEfiNotAvailableYetArg5 (
 }

 

 /**

-  Software MMI handler that is called when a Legacy Boot event is signaled.  The MM

-  Core uses this signal to know that a Legacy Boot has been performed and that

-  gMmCorePrivate that is shared between the UEFI and MM execution environments can

-  not be accessed from MM anymore since that structure is considered free memory by

-  a legacy OS.

-

-  @param  DispatchHandle  The unique handle assigned to this handler by MmiHandlerRegister().

-  @param  Context         Points to an optional handler context which was specified when the handler was registered.

-  @param  CommBuffer      A pointer to a collection of data in memory that will

-                          be conveyed from a non-MM environment into an MM environment.

-  @param  CommBufferSize  The size of the CommBuffer.

-

-  @return Status Code

-

-**/

-EFI_STATUS

-EFIAPI

-MmLegacyBootHandler (

-  IN     EFI_HANDLE  DispatchHandle,

-  IN     CONST VOID  *Context,        OPTIONAL

-  IN OUT VOID        *CommBuffer,     OPTIONAL

-  IN OUT UINTN       *CommBufferSize  OPTIONAL

-  )

-{

-  EFI_HANDLE  MmHandle;

-  EFI_STATUS  Status = EFI_SUCCESS;

-

-  if (!mInLegacyBoot) {

-    MmHandle = NULL;

-    Status = MmInstallProtocolInterface (

-               &MmHandle,

-               &gEfiEventLegacyBootGuid,

-               EFI_NATIVE_INTERFACE,

-               NULL

-               );

-  }

-  mInLegacyBoot = TRUE;

-  return Status;

-}

-

-/**

   Software MMI handler that is called when a ExitBoot Service event is signaled.

 

   @param  DispatchHandle  The unique handle assigned to this handler by MmiHandlerRegister().

@@ -396,7 +346,6 @@ MmEntryPoint (
 {

   EFI_STATUS                  Status;

   EFI_MM_COMMUNICATE_HEADER  *CommunicateHeader;

-  BOOLEAN                     InLegacyBoot;

 

   DEBUG ((DEBUG_INFO, "MmEntryPoint ...\n"));

 

@@ -413,44 +362,42 @@ MmEntryPoint (
   //

   // If a legacy boot has occured, then make sure gMmCorePrivate is not accessed

   //

-  InLegacyBoot = mInLegacyBoot;

-  if (!InLegacyBoot) {

-    //

-    // TBD: Mark the InMm flag as TRUE

-    //

-    gMmCorePrivate->InMm = TRUE;

 

+  //

+  // TBD: Mark the InMm flag as TRUE

+  //

+  gMmCorePrivate->InMm = TRUE;

+

+  //

+  // Check to see if this is a Synchronous MMI sent through the MM Communication

+  // Protocol or an Asynchronous MMI

+  //

+  if (gMmCorePrivate->CommunicationBuffer != 0) {

     //

-    // Check to see if this is a Synchronous MMI sent through the MM Communication

-    // Protocol or an Asynchronous MMI

+    // Synchronous MMI for MM Core or request from Communicate protocol

     //

-    if (gMmCorePrivate->CommunicationBuffer != 0) {

+    if (!MmIsBufferOutsideMmValid ((UINTN)gMmCorePrivate->CommunicationBuffer, gMmCorePrivate->BufferSize)) {

+      //

+      // If CommunicationBuffer is not in valid address scope, return EFI_INVALID_PARAMETER

       //

-      // Synchronous MMI for MM Core or request from Communicate protocol

+      gMmCorePrivate->CommunicationBuffer = 0;

+      gMmCorePrivate->ReturnStatus = EFI_INVALID_PARAMETER;

+    } else {

+      CommunicateHeader = (EFI_MM_COMMUNICATE_HEADER *)(UINTN)gMmCorePrivate->CommunicationBuffer;

+      gMmCorePrivate->BufferSize -= OFFSET_OF (EFI_MM_COMMUNICATE_HEADER, Data);

+      Status = MmiManage (

+                 &CommunicateHeader->HeaderGuid,

+                 NULL,

+                 CommunicateHeader->Data,

+                 (UINTN *)&gMmCorePrivate->BufferSize

+                 );

       //

-      if (!MmIsBufferOutsideMmValid ((UINTN)gMmCorePrivate->CommunicationBuffer, gMmCorePrivate->BufferSize)) {

-        //

-        // If CommunicationBuffer is not in valid address scope, return EFI_INVALID_PARAMETER

-        //

-        gMmCorePrivate->CommunicationBuffer = 0;

-        gMmCorePrivate->ReturnStatus = EFI_INVALID_PARAMETER;

-      } else {

-        CommunicateHeader = (EFI_MM_COMMUNICATE_HEADER *)(UINTN)gMmCorePrivate->CommunicationBuffer;

-        gMmCorePrivate->BufferSize -= OFFSET_OF (EFI_MM_COMMUNICATE_HEADER, Data);

-        Status = MmiManage (

-                   &CommunicateHeader->HeaderGuid,

-                   NULL,

-                   CommunicateHeader->Data,

-                   (UINTN *)&gMmCorePrivate->BufferSize

-                   );

-        //

-        // Update CommunicationBuffer, BufferSize and ReturnStatus

-        // Communicate service finished, reset the pointer to CommBuffer to NULL

-        //

-        gMmCorePrivate->BufferSize += OFFSET_OF (EFI_MM_COMMUNICATE_HEADER, Data);

-        gMmCorePrivate->CommunicationBuffer = 0;

-        gMmCorePrivate->ReturnStatus = (Status == EFI_SUCCESS) ? EFI_SUCCESS : EFI_NOT_FOUND;

-      }

+      // Update CommunicationBuffer, BufferSize and ReturnStatus

+      // Communicate service finished, reset the pointer to CommBuffer to NULL

+      //

+      gMmCorePrivate->BufferSize += OFFSET_OF (EFI_MM_COMMUNICATE_HEADER, Data);

+      gMmCorePrivate->CommunicationBuffer = 0;

+      gMmCorePrivate->ReturnStatus = (Status == EFI_SUCCESS) ? EFI_SUCCESS : EFI_NOT_FOUND;

     }

   }

 

@@ -464,14 +411,9 @@ MmEntryPoint (
   //

 

   //

-  // If a legacy boot has occured, then make sure gMmCorePrivate is not accessed

+  // Clear the InMm flag as we are going to leave MM

   //

-  if (!InLegacyBoot) {

-    //

-    // Clear the InMm flag as we are going to leave MM

-    //

-    gMmCorePrivate->InMm = FALSE;

-  }

+  gMmCorePrivate->InMm = FALSE;

 

   DEBUG ((DEBUG_INFO, "MmEntryPoint Done\n"));

 }

diff --git a/StandaloneMmPkg/Core/StandaloneMmCore.h b/StandaloneMmPkg/Core/StandaloneMmCore.h
index 74338dc9da..5d336b3dbb 100644
--- a/StandaloneMmPkg/Core/StandaloneMmCore.h
+++ b/StandaloneMmPkg/Core/StandaloneMmCore.h
@@ -638,28 +638,6 @@ MmDriverDispatchHandler (
 **/

 EFI_STATUS

 EFIAPI

-MmLegacyBootHandler (

-  IN     EFI_HANDLE               DispatchHandle,

-  IN     CONST VOID               *Context,        OPTIONAL

-  IN OUT VOID                     *CommBuffer,     OPTIONAL

-  IN OUT UINTN                    *CommBufferSize  OPTIONAL

-  );

-

-/**

-  This function is the main entry point for an MM handler dispatch

-  or communicate-based callback.

-

-  @param  DispatchHandle  The unique handle assigned to this handler by MmiHandlerRegister().

-  @param  Context         Points to an optional handler context which was specified when the handler was registered.

-  @param  CommBuffer      A pointer to a collection of data in memory that will

-                          be conveyed from a non-MM environment into an MM environment.

-  @param  CommBufferSize  The size of the CommBuffer.

-

-  @return Status Code

-

-**/

-EFI_STATUS

-EFIAPI

 MmExitBootServiceHandler (

   IN     EFI_HANDLE               DispatchHandle,

   IN     CONST VOID               *Context,        OPTIONAL