UefiCpuPkg/MpInitLib: Use AmdSvsmSnpVmsaRmpAdjust() to set/clear VMSA

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4654

The RMPADJUST instruction is used to change the VMSA attribute of a page,
but the VMSA attribute can only be changed when running at VMPL0. To
prepare for running at a less priviledged VMPL, use the AmdSvsmLib library
API to perform the RMPADJUST. The AmdSvsmLib library will perform the
proper operation on behalf of the caller.

Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Acked-by: Ray Ni <ray.ni@intel.com>

5 files changed, 9 insertions, 81 deletions

diff --git a/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf b/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
index 15c10b3060..41d5a80bc9 100644
--- a/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
+++ b/UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
@@ -62,6 +62,7 @@
   UefiBootServicesTableLib

 

 [LibraryClasses.IA32, LibraryClasses.X64]

+  AmdSvsmLib

   CcExitLib

   LocalApicLib

   MicrocodeLib

diff --git a/UefiCpuPkg/Library/MpInitLib/Ia32/AmdSev.c b/UefiCpuPkg/Library/MpInitLib/Ia32/AmdSev.c
index 0478e92317..963bd62494 100644
--- a/UefiCpuPkg/Library/MpInitLib/Ia32/AmdSev.c
+++ b/UefiCpuPkg/Library/MpInitLib/Ia32/AmdSev.c
@@ -50,26 +50,6 @@ SevSnpCreateAP (
 }

 

 /**

-  Issue RMPADJUST to adjust the VMSA attribute of an SEV-SNP page.

-

-  @param[in]  PageAddress

-  @param[in]  VmsaPage

-

-  @return  RMPADJUST return value

-**/

-UINT32

-SevSnpRmpAdjust (

-  IN  EFI_PHYSICAL_ADDRESS  PageAddress,

-  IN  BOOLEAN               VmsaPage

-  )

-{

-  //

-  // RMPADJUST is not supported in 32-bit mode

-  //

-  return RETURN_UNSUPPORTED;

-}

-

-/**

   Determine if the SEV-SNP AP Create protocol should be used.

 

   @param[in]  CpuMpData  Pointer to CPU MP Data

diff --git a/UefiCpuPkg/Library/MpInitLib/MpLib.h b/UefiCpuPkg/Library/MpInitLib/MpLib.h
index 65e05c4806..179f8e585b 100644
--- a/UefiCpuPkg/Library/MpInitLib/MpLib.h
+++ b/UefiCpuPkg/Library/MpInitLib/MpLib.h
@@ -884,20 +884,6 @@ FillExchangeInfoDataSevEs (
   );

 

 /**

-  Issue RMPADJUST to adjust the VMSA attribute of an SEV-SNP page.

-

-  @param[in]  PageAddress

-  @param[in]  VmsaPage

-

-  @return  RMPADJUST return value

-**/

-UINT32

-SevSnpRmpAdjust (

-  IN  EFI_PHYSICAL_ADDRESS  PageAddress,

-  IN  BOOLEAN               VmsaPage

-  );

-

-/**

   Create an SEV-SNP AP save area (VMSA) for use in running the vCPU.

 

   @param[in]  CpuMpData        Pointer to CPU MP Data

diff --git a/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf b/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf
index 6c75b96fdc..e31e34b6f9 100644
--- a/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf
+++ b/UefiCpuPkg/Library/MpInitLib/PeiMpInitLib.inf
@@ -59,6 +59,7 @@
   SynchronizationLib

 

 [LibraryClasses.IA32, LibraryClasses.X64]

+  AmdSvsmLib

   CcExitLib

   LocalApicLib

   MicrocodeLib

diff --git a/UefiCpuPkg/Library/MpInitLib/X64/AmdSev.c b/UefiCpuPkg/Library/MpInitLib/X64/AmdSev.c
index bd12a5ee2f..9811356213 100644
--- a/UefiCpuPkg/Library/MpInitLib/X64/AmdSev.c
+++ b/UefiCpuPkg/Library/MpInitLib/X64/AmdSev.c
@@ -10,6 +10,7 @@
 

 #include "MpLib.h"

 #include <Library/CcExitLib.h>

+#include <Library/AmdSvsmLib.h>

 #include <Register/Amd/Fam17Msr.h>

 #include <Register/Amd/Ghcb.h>

 

@@ -38,20 +39,15 @@ SevSnpPerformApAction (
   BOOLEAN                   InterruptState;

   UINT64                    ExitInfo1;

   UINT64                    ExitInfo2;

-  UINT32                    RmpAdjustStatus;

   UINT64                    VmgExitStatus;

+  EFI_STATUS                VmsaStatus;

 

   if (Action == SVM_VMGEXIT_SNP_AP_CREATE) {

     //

-    // To turn the page into a recognized VMSA page, issue RMPADJUST:

-    //   Target VMPL but numerically higher than current VMPL

-    //   Target PermissionMask is not used

+    // Turn the page into a recognized VMSA page.

     //

-    RmpAdjustStatus = SevSnpRmpAdjust (

-                        (EFI_PHYSICAL_ADDRESS)(UINTN)SaveArea,

-                        TRUE

-                        );

-    if (RmpAdjustStatus != 0) {

+    VmsaStatus = AmdSvsmSnpVmsaRmpAdjust (SaveArea, ApicId, TRUE);

+    if (EFI_ERROR (VmsaStatus)) {

       DEBUG ((DEBUG_INFO, "SEV-SNP: RMPADJUST failed for VMSA creation\n"));

       ASSERT (FALSE);

 

@@ -94,11 +90,8 @@ SevSnpPerformApAction (
     // Make the current VMSA not runnable and accessible to be

     // reprogrammed.

     //

-    RmpAdjustStatus = SevSnpRmpAdjust (

-                        (EFI_PHYSICAL_ADDRESS)(UINTN)SaveArea,

-                        FALSE

-                        );

-    if (RmpAdjustStatus != 0) {

+    VmsaStatus = AmdSvsmSnpVmsaRmpAdjust (SaveArea, ApicId, FALSE);

+    if (EFI_ERROR (VmsaStatus)) {

       DEBUG ((DEBUG_INFO, "SEV-SNP: RMPADJUST failed for VMSA reset\n"));

       ASSERT (FALSE);

 

@@ -329,39 +322,6 @@ SevSnpCreateAP (
 }

 

 /**

-  Issue RMPADJUST to adjust the VMSA attribute of an SEV-SNP page.

-

-  @param[in]  PageAddress

-  @param[in]  VmsaPage

-

-  @return  RMPADJUST return value

-**/

-UINT32

-SevSnpRmpAdjust (

-  IN  EFI_PHYSICAL_ADDRESS  PageAddress,

-  IN  BOOLEAN               VmsaPage

-  )

-{

-  UINT64  Rdx;

-

-  //

-  // The RMPADJUST instruction is used to set or clear the VMSA bit for a

-  // page. The VMSA change is only made when running at VMPL0 and is ignored

-  // otherwise. If too low a target VMPL is specified, the instruction can

-  // succeed without changing the VMSA bit when not running at VMPL0. Using a

-  // target VMPL level of 1, RMPADJUST will return a FAIL_PERMISSION error if

-  // not running at VMPL0, thus ensuring that the VMSA bit is set appropriately

-  // when no error is returned.

-  //

-  Rdx = 1;

-  if (VmsaPage) {

-    Rdx |= RMPADJUST_VMSA_PAGE_BIT;

-  }

-

-  return AsmRmpAdjust ((UINT64)PageAddress, 0, Rdx);

-}

-

-/**

   Determine if the SEV-SNP AP Create protocol should be used.

 

   @param[in]  CpuMpData  Pointer to CPU MP Data