[PATCH v2] OvmfPkg: set a default value for the WorkAreaHeader PCD


Corvin Köhne
 

SEC checks in IsSevGuest if the PCD defined WorkAreaHeader size matches the size of the WorkAreaHeader struct definition. Set a default value for the PCD to avoid unnecessary DSC/FDF file changes in all OVMF DSC/FDF files.

Signed-off-by: Corvin Köhne <c.koehne@beckhoff.com>
---
OvmfPkg/Include/WorkArea.h | 4 ++++
OvmfPkg/OvmfPkg.dec | 7 ++++++-
OvmfPkg/OvmfPkgDefines.fdf.inc | 6 ------
3 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/OvmfPkg/Include/WorkArea.h b/OvmfPkg/Include/WorkArea.h
index c16030e3ac..0f9b442e43 100644
--- a/OvmfPkg/Include/WorkArea.h
+++ b/OvmfPkg/Include/WorkArea.h
@@ -25,6 +25,10 @@ typedef enum {
// to the structure need to be kept in sync with the
// PcdOvmfConfidentialComputingWorkAreaHeader.
//
+// PcdOvmfConfidentialComputingWorkAreaHeader ==
+// sizeof (CONFIDENTIAL_COMPUTING_WORK_AREA_HEADER)
+//
+// PcdOvmfConfidentialComputingWorkAreaHeader defined in OvmfPkg/OvmfPkg.dec
typedef struct _CONFIDENTIAL_COMPUTING_WORK_AREA_HEADER {
UINT8 GuestType;
UINT8 Reserved1[3];
diff --git a/OvmfPkg/OvmfPkg.dec b/OvmfPkg/OvmfPkg.dec
index 75d47e0e00..3ed3811320 100644
--- a/OvmfPkg/OvmfPkg.dec
+++ b/OvmfPkg/OvmfPkg.dec
@@ -339,7 +339,12 @@
# The size of this header is used early boot, and is provided through
# a fixed PCD. It need to be kept in sync with any changes to the
# header definition.
- gUefiOvmfPkgTokenSpaceGuid.PcdOvmfConfidentialComputingWorkAreaHeader|0|UINT32|0x51
+ #
+ # PcdOvmfConfidentialComputingWorkAreaHeader ==
+ # sizeof (CONFIDENTIAL_COMPUTING_WORK_AREA_HEADER)
+ #
+ # CONFIDENTIAL_COMPUTING_WORK_AREA_HEADER defined in OvmfPkg/Include/WorkArea.h
+ gUefiOvmfPkgTokenSpaceGuid.PcdOvmfConfidentialComputingWorkAreaHeader|4|UINT32|0x51


[PcdsDynamic, PcdsDynamicEx]
diff --git a/OvmfPkg/OvmfPkgDefines.fdf.inc b/OvmfPkg/OvmfPkgDefines.fdf.inc
index 3b5e452539..35fd454b97 100644
--- a/OvmfPkg/OvmfPkgDefines.fdf.inc
+++ b/OvmfPkg/OvmfPkgDefines.fdf.inc
@@ -82,12 +82,6 @@ SET gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingSize = $(BLOCK_SIZ
SET gUefiOvmfPkgTokenSpaceGuid.PcdOvmfFlashNvStorageFtwSpareBase = gUefiOvmfPkgTokenSpaceGuid.PcdOvmfFlashNvStorageFtwWorkingBase + gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingSize
SET gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwSpareSize = $(VARS_SPARE_SIZE)

-# The OVMF WorkArea contains a fixed size header followed by the actual data.
-# The size of header is accessed through a fixed PCD in the reset vector code.
-# The value need to be kept in sync with the any changes to the Confidential
-# Computing Work Area header defined in the Include/WorkArea.h
-SET gUefiOvmfPkgTokenSpaceGuid.PcdOvmfConfidentialComputingWorkAreaHeader = 4
-
!if $(SMM_REQUIRE) == TRUE
SET gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableBase64 = gUefiOvmfPkgTokenSpaceGuid.PcdOvmfFlashNvStorageVariableBase
SET gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingBase = gUefiOvmfPkgTokenSpaceGuid.PcdOvmfFlashNvStorageFtwWorkingBase
--
2.11.0

Beckhoff Automation GmbH & Co. KG | Managing Director: Dipl. Phys. Hans Beckhoff Registered office: Verl, Germany | Register court: Guetersloh HRA 7075


Yao, Jiewen
 

Reviewed-by: Jiewen Yao <Jiewen.yao@intel.com>

-----Original Message-----
From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Corvin
Köhne
Sent: Thursday, September 16, 2021 2:22 PM
To: devel@edk2.groups.io
Cc: ardb+tianocore@kernel.org; Yao, Jiewen <jiewen.yao@intel.com>; Justen,
Jordan L <jordan.l.justen@intel.com>; kraxel@redhat.com; rebecca@bsdio.com;
grehan@freebsd.org; Köhne, Corvin <c.koehne@beckhoff.com>
Subject: [edk2-devel] [PATCH v2] OvmfPkg: set a default value for the
WorkAreaHeader PCD

SEC checks in IsSevGuest if the PCD defined WorkAreaHeader size matches the
size of the WorkAreaHeader struct definition. Set a default value for the PCD to
avoid unnecessary DSC/FDF file changes in all OVMF DSC/FDF files.

Signed-off-by: Corvin Köhne <c.koehne@beckhoff.com>
---
OvmfPkg/Include/WorkArea.h | 4 ++++
OvmfPkg/OvmfPkg.dec | 7 ++++++-
OvmfPkg/OvmfPkgDefines.fdf.inc | 6 ------
3 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/OvmfPkg/Include/WorkArea.h b/OvmfPkg/Include/WorkArea.h
index c16030e3ac..0f9b442e43 100644
--- a/OvmfPkg/Include/WorkArea.h
+++ b/OvmfPkg/Include/WorkArea.h
@@ -25,6 +25,10 @@ typedef enum {
// to the structure need to be kept in sync with the
// PcdOvmfConfidentialComputingWorkAreaHeader.
//
+// PcdOvmfConfidentialComputingWorkAreaHeader ==
+// sizeof (CONFIDENTIAL_COMPUTING_WORK_AREA_HEADER)
+//
+// PcdOvmfConfidentialComputingWorkAreaHeader defined in
OvmfPkg/OvmfPkg.dec
typedef struct _CONFIDENTIAL_COMPUTING_WORK_AREA_HEADER {
UINT8 GuestType;
UINT8 Reserved1[3];
diff --git a/OvmfPkg/OvmfPkg.dec b/OvmfPkg/OvmfPkg.dec
index 75d47e0e00..3ed3811320 100644
--- a/OvmfPkg/OvmfPkg.dec
+++ b/OvmfPkg/OvmfPkg.dec
@@ -339,7 +339,12 @@
# The size of this header is used early boot, and is provided through
# a fixed PCD. It need to be kept in sync with any changes to the
# header definition.
-
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfConfidentialComputingWorkAreaHeade
r|0|UINT32|0x51
+ #
+ # PcdOvmfConfidentialComputingWorkAreaHeader ==
+ # sizeof (CONFIDENTIAL_COMPUTING_WORK_AREA_HEADER)
+ #
+ # CONFIDENTIAL_COMPUTING_WORK_AREA_HEADER defined in
OvmfPkg/Include/WorkArea.h
+
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfConfidentialComputingWorkAreaHeade
r|4|UINT32|0x51


[PcdsDynamic, PcdsDynamicEx]
diff --git a/OvmfPkg/OvmfPkgDefines.fdf.inc
b/OvmfPkg/OvmfPkgDefines.fdf.inc
index 3b5e452539..35fd454b97 100644
--- a/OvmfPkg/OvmfPkgDefines.fdf.inc
+++ b/OvmfPkg/OvmfPkgDefines.fdf.inc
@@ -82,12 +82,6 @@ SET
gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingSize =
$(BLOCK_SIZ
SET gUefiOvmfPkgTokenSpaceGuid.PcdOvmfFlashNvStorageFtwSpareBase =
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfFlashNvStorageFtwWorkingBase +
gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingSize
SET gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwSpareSize =
$(VARS_SPARE_SIZE)

-# The OVMF WorkArea contains a fixed size header followed by the actual data.
-# The size of header is accessed through a fixed PCD in the reset vector code.
-# The value need to be kept in sync with the any changes to the Confidential
-# Computing Work Area header defined in the Include/WorkArea.h
-SET
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfConfidentialComputingWorkAreaHeade
r = 4
-
!if $(SMM_REQUIRE) == TRUE
SET gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableBase64 =
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfFlashNvStorageVariableBase
SET gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingBase =
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfFlashNvStorageFtwWorkingBase
--
2.11.0

Beckhoff Automation GmbH & Co. KG | Managing Director: Dipl. Phys. Hans
Beckhoff Registered office: Verl, Germany | Register court: Guetersloh HRA
7075