Re: [PATCH 2/4] MdeModulePkg/DxeCore: invoke the emulator protocol for foreign images

["Zeng, Star" <star.zeng@intel.com>]

On 2018/9/12 21:21, Ard Biesheuvel wrote:
> When encountering PE/COFF images that cannot be supported natively,
> attempt to locate an instance of the PE/COFF image emulator protocol,
> and if it supports the image, proceed with loading it and register it
> with the emulator.
> 
> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
>   MdeModulePkg/Core/Dxe/DxeMain.h     |  3 ++
>   MdeModulePkg/Core/Dxe/DxeMain.inf   |  1 +
>   MdeModulePkg/Core/Dxe/Image/Image.c | 39 +++++++++++++++++---
>   3 files changed, 37 insertions(+), 6 deletions(-)
> 
> diff --git a/MdeModulePkg/Core/Dxe/DxeMain.h b/MdeModulePkg/Core/Dxe/DxeMain.h
> index 7ec82388a3f9..57b3861d9813 100644
> --- a/MdeModulePkg/Core/Dxe/DxeMain.h
> +++ b/MdeModulePkg/Core/Dxe/DxeMain.h
> @@ -53,6 +53,7 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
>   #include <Protocol/TcgService.h>
>   #include <Protocol/HiiPackageList.h>
>   #include <Protocol/SmmBase2.h>
> +#include <Protocol/PeCoffImageEmulator.h>
>   #include <Guid/MemoryTypeInformation.h>
>   #include <Guid/FirmwareFileSystem2.h>
>   #include <Guid/FirmwareFileSystem3.h>
> @@ -229,6 +230,8 @@ typedef struct {
>     UINT16                      Machine;
>     /// EBC Protocol pointer
>     EFI_EBC_PROTOCOL            *Ebc;
> +  /// PE/COFF Image Emulator Protocol pointer
> +  EDKII_PECOFF_IMAGE_EMULATOR_PROTOCOL  *Emu;

Hi Ard,

How about using PeCoffEmu as the name to be more specific?

>     /// Runtime image list
>     EFI_RUNTIME_IMAGE_ENTRY     *RuntimeData;
>     /// Pointer to Loaded Image Device Path Protocol
> diff --git a/MdeModulePkg/Core/Dxe/DxeMain.inf b/MdeModulePkg/Core/Dxe/DxeMain.inf
> index 68fa0a01d9bd..d7591aa0da6d 100644
> --- a/MdeModulePkg/Core/Dxe/DxeMain.inf
> +++ b/MdeModulePkg/Core/Dxe/DxeMain.inf
> @@ -180,6 +180,7 @@
>     gEfiVariableArchProtocolGuid                  ## CONSUMES
>     gEfiCapsuleArchProtocolGuid                   ## CONSUMES
>     gEfiWatchdogTimerArchProtocolGuid             ## CONSUMES
> +  gEdkiiPeCoffImageEmulatorProtocolGuid         ## SOMETIMES_CONSUMES
>   
>   [FeaturePcd]
>     gEfiMdeModulePkgTokenSpaceGuid.PcdFrameworkCompatibilitySupport     ## CONSUMES
> diff --git a/MdeModulePkg/Core/Dxe/Image/Image.c b/MdeModulePkg/Core/Dxe/Image/Image.c
> index eddca140ee1a..e2dd80790657 100644
> --- a/MdeModulePkg/Core/Dxe/Image/Image.c
> +++ b/MdeModulePkg/Core/Dxe/Image/Image.c
> @@ -67,6 +67,7 @@ LOADED_IMAGE_PRIVATE_DATA mCorePrivateImage  = {
>     NULL,                       // JumpContext
>     0,                          // Machine
>     NULL,                       // Ebc
> +  NULL,                       // Emu
>     NULL,                       // RuntimeData
>     NULL                        // LoadedImageDevicePath
>   };
> @@ -476,12 +477,23 @@ CoreLoadPeImage (
>     if (!EFI_IMAGE_MACHINE_TYPE_SUPPORTED (Image->ImageContext.Machine)) {
>       if (!EFI_IMAGE_MACHINE_CROSS_TYPE_SUPPORTED (Image->ImageContext.Machine)) {
>         //
> -      // The PE/COFF loader can support loading image types that can be executed.
> -      // If we loaded an image type that we can not execute return EFI_UNSUPORTED.
> +      // Locate the emulator protocol to check whether it supports this
> +      // image.
>         //
> -      DEBUG ((EFI_D_ERROR, "Image type %s can't be loaded ", GetMachineTypeName(Image->ImageContext.Machine)));
> -      DEBUG ((EFI_D_ERROR, "on %s UEFI system.\n", GetMachineTypeName(mDxeCoreImageMachineType)));
> -      return EFI_UNSUPPORTED;
> +      Status = CoreLocateProtocol (&gEdkiiPeCoffImageEmulatorProtocolGuid,
> +                 NULL, (VOID **)&Image->Emu);
> +      if (EFI_ERROR (Status) ||
> +          !Image->Emu->IsImageSupported (Image->Emu,
> +                                         Image->ImageContext.Machine,
> +                                         Image->ImageContext.ImageType)) {
> +        //
> +        // The PE/COFF loader can support loading image types that can be executed.
> +        // If we loaded an image type that we can not execute return EFI_UNSUPORTED.
> +        //
> +        DEBUG ((EFI_D_ERROR, "Image type %s can't be loaded ", GetMachineTypeName(Image->ImageContext.Machine)));
> +        DEBUG ((EFI_D_ERROR, "on %s UEFI system.\n", GetMachineTypeName(mDxeCoreImageMachineType)));
> +        return EFI_UNSUPPORTED;
> +      }
>       }
>     }
>   
> @@ -687,6 +699,14 @@ CoreLoadPeImage (
>       if (EFI_ERROR(Status)) {
>         goto Done;
>       }
> +  } else if (Image->Emu != NULL) {
> +    Status = Image->Emu->RegisterImage (Image->Emu, Image->ImageBasePage,
> +                           EFI_PAGES_TO_SIZE (Image->NumberOfPages));
> +    if (EFI_ERROR (Status)) {
> +      DEBUG ((DEBUG_LOAD | DEBUG_ERROR,
> +        "CoreLoadPeImage: Failed to load register foreign image with emulator.\n"));

'load' should not be in the sentence, right?

Thanks,
Star

> +      goto Done;
> +    }
>     }
>   
>     //
> @@ -874,6 +894,13 @@ CoreUnloadAndCloseImage (
>       Image->Ebc->UnloadImage (Image->Ebc, Image->Handle);
>     }
>   
> +  if (Image->Emu != NULL) {
> +    //
> +    // If the PE/COFF Emulator protocol exists we must unregister the image.
> +    //
> +    Image->Emu->UnregisterImage (Image->Emu, Image->ImageBasePage);
> +  }
> +
>     //
>     // Unload image, free Image->ImageContext->ModHandle
>     //
> @@ -1599,7 +1626,7 @@ CoreStartImage (
>     //
>     // The image to be started must have the machine type supported by DxeCore.
>     //
> -  if (!EFI_IMAGE_MACHINE_TYPE_SUPPORTED (Image->Machine)) {
> +  if (!EFI_IMAGE_MACHINE_TYPE_SUPPORTED (Image->Machine) && Image->Emu == NULL) {
>       //
>       // Do not ASSERT here, because image might be loaded via EFI_IMAGE_MACHINE_CROSS_TYPE_SUPPORTED
>       // But it can not be started.
>