The trigger to actually save the boot script is the installation of
EFI_DXE_SMM_READY_TO_LOCK_PROTOCOL, to be performed by any DXE driver.
Installation of the protocol also locks down SMM (as its name indicates)
and prevents further LockBox access.

We cannot install this protocol before BdsLibBootViaBootOption() is called
(eg. in OVMF's PlatformBdsPolicyBehavior()), because
BdsLibBootViaBootOption() calls EFI_ACPI_S3_SAVE_PROTOCOL.S3Save(), which
needs LockBox access.

We also can't install the protocol after BdsLibBootViaBootOption()
returns, simply because control is never returned to us.

Therefore modify our EFI_ACPI_S3_SAVE_PROTOCOL implementation so that the
boot script is prepared and installed internally to S3Save().

(The boot script must contain at least one opcode, otherwise
S3BootScriptLib runs into an assertion failure. We add a harmless (no-op)
"information" opcode.)

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <ler...@redhat.com>
---
 OvmfPkg/AcpiS3SaveDxe/AcpiS3SaveDxe.inf |  4 ++-
 OvmfPkg/AcpiS3SaveDxe/AcpiS3Save.c      | 49 +++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+), 1 deletion(-)

diff --git a/OvmfPkg/AcpiS3SaveDxe/AcpiS3SaveDxe.inf 
b/OvmfPkg/AcpiS3SaveDxe/AcpiS3SaveDxe.inf
index 169e400..159cdb8 100644
--- a/OvmfPkg/AcpiS3SaveDxe/AcpiS3SaveDxe.inf
+++ b/OvmfPkg/AcpiS3SaveDxe/AcpiS3SaveDxe.inf
@@ -62,6 +62,8 @@
   gEfiLegacyBiosProtocolGuid                    # PROTOCOL ALWAYS_CONSUMED
   gEfiLegacyRegion2ProtocolGuid                 # PROTOCOL SOMETIMES_CONSUMED
   gFrameworkEfiMpServiceProtocolGuid            # PROTOCOL SOMETIMES_CONSUMED
+  gEfiS3SaveStateProtocolGuid                   # PROTOCOL ALWAYS_CONSUMED
+  gEfiDxeSmmReadyToLockProtocolGuid             # PROTOCOL ALWAYS_CONSUMED
 
 [FeaturePcd]
   gEfiIntelFrameworkModulePkgTokenSpaceGuid.PcdPlatformCsmSupport          ## 
CONSUMES
@@ -73,4 +75,4 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdUse1GPageTable
 
 [Depex]
-  gEfiVariableArchProtocolGuid AND gEfiVariableWriteArchProtocolGuid
+  gEfiVariableArchProtocolGuid AND gEfiVariableWriteArchProtocolGuid AND 
gEfiS3SaveStateProtocolGuid
diff --git a/OvmfPkg/AcpiS3SaveDxe/AcpiS3Save.c 
b/OvmfPkg/AcpiS3SaveDxe/AcpiS3Save.c
index 80f12eb..684ddb7 100644
--- a/OvmfPkg/AcpiS3SaveDxe/AcpiS3Save.c
+++ b/OvmfPkg/AcpiS3SaveDxe/AcpiS3Save.c
@@ -28,6 +28,8 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER 
EXPRESS OR IMPLIED.
 #include <Guid/AcpiS3Context.h>
 #include <Guid/Acpi.h>
 #include <Protocol/AcpiS3Save.h>
+#include <Protocol/S3SaveState.h>
+#include <Protocol/DxeSmmReadyToLock.h>
 #include <IndustryStandard/Acpi.h>
 
 #include "AcpiS3Save.h"
@@ -407,6 +409,48 @@ LegacyGetS3MemorySize (
 }
 
 /**
+  Save the S3 boot script.
+
+  Note that we trigger DxeSmmReadyToLock here -- otherwise the script wouldn't
+  be saved actually. Triggering this protocol installation event in turn locks
+  down SMM, so no further changes to LockBoxes or SMRAM are possible
+  afterwards.
+**/
+STATIC
+VOID
+EFIAPI
+SaveS3BootScript (
+  VOID
+  )
+{
+  EFI_STATUS                 Status;
+  EFI_S3_SAVE_STATE_PROTOCOL *BootScript;
+  EFI_HANDLE                 Handle;
+  STATIC CONST UINT8         Info[] = { 0xDE, 0xAD, 0xBE, 0xEF };
+
+  Status = gBS->LocateProtocol (&gEfiS3SaveStateProtocolGuid, NULL,
+                  (VOID **) &BootScript);
+  ASSERT_EFI_ERROR (Status);
+
+  //
+  // Despite the opcode documentation in the PI spec, the protocol
+  // implementation embeds a deep copy of the info in the boot script, rather
+  // than storing just a pointer to runtime or NVS storage.
+  //
+  Status = BootScript->Write(BootScript, EFI_BOOT_SCRIPT_INFORMATION_OPCODE,
+                         (UINT32) sizeof Info,
+                         (EFI_PHYSICAL_ADDRESS)(UINTN) &Info);
+  ASSERT_EFI_ERROR (Status);
+
+  Handle = NULL;
+  Status = gBS->InstallProtocolInterface (&Handle,
+                  &gEfiDxeSmmReadyToLockProtocolGuid, EFI_NATIVE_INTERFACE,
+                  NULL);
+  ASSERT_EFI_ERROR (Status);
+}
+
+
+/**
   Prepares all information that is needed in the S3 resume boot path.
   
   Allocate the resources or prepare informations and save in ACPI variable set 
for S3 resume boot path  
@@ -511,6 +555,11 @@ S3Ready (
   Status = SetLockBoxAttributes (&gEfiAcpiS3ContextGuid, 
LOCK_BOX_ATTRIBUTE_RESTORE_IN_PLACE);
   ASSERT_EFI_ERROR (Status);
 
+  //
+  // Save the boot script too. Note that this requires/includes emitting the
+  // DxeSmmReadyToLock event, which in turn locks down SMM.
+  //
+  SaveS3BootScript ();
   return EFI_SUCCESS;
 }
 
-- 
1.8.3.1



------------------------------------------------------------------------------
Sponsored by Intel(R) XDK 
Develop, test and display web and hybrid apps with a single code base.
Download it for free now!
http://pubads.g.doubleclick.net/gampad/clk?id=111408631&iu=/4140/ostg.clktrk
_______________________________________________
edk2-devel mailing list
edk2-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/edk2-devel

Reply via email to