diff --git a/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c b/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c
index 6293843f32..8519642a8c 100644
--- a/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c
+++ b/ArmPkg/Library/DefaultExceptionHandlerLib/Arm/DefaultExceptionHandler.c
@@ -227,7 +227,7 @@ DefaultExceptionHandler (
     return mSysCallHandler (
              SystemContext.SystemContextArm->R0,
              &(SystemContext.SystemContextArm->R1),
-             &(SystemContext.SystemContextArm->SP)
+             (VOID *)SystemContext.SystemContextArm->SP
              );
   }
 
diff --git a/MdeModulePkg/Core/Dxe/SysCall/ARM/InitializeMsr.c b/MdeModulePkg/Core/Dxe/SysCall/ARM/InitializeMsr.c
index 8fc8db82ad..eb6d555734 100644
--- a/MdeModulePkg/Core/Dxe/SysCall/ARM/InitializeMsr.c
+++ b/MdeModulePkg/Core/Dxe/SysCall/ARM/InitializeMsr.c
@@ -71,11 +71,11 @@ SysCallBootService (
   //
   // First 3 arguments are passed through R1-R3 and copied to SysCall Stack.
   //
-  CopyMem ((VOID *)((UINTN)Physical + sizeof (UINTN)), (VOID *)CoreRbp, 3 * sizeof (UINTN));
+  CopyMem ((VOID *)((UINTN)Physical + 2 * sizeof (UINTN)), (VOID *)CoreRbp, 3 * sizeof (UINTN));
   //
   // All remaining arguments are on User Stack.
   //
-  CopyMem ((VOID *)((UINTN)Physical + 4 * sizeof (UINTN)), (VOID *)UserRsp, 5 * sizeof (UINTN));
+  CopyMem ((VOID *)((UINTN)Physical + 5 * sizeof (UINTN)), (VOID *)UserRsp, 4 * sizeof (UINTN));
   EnableSMAP ();
 
   Status = CallBootService (
diff --git a/MdeModulePkg/Core/Dxe/SysCall/SupportedProtocols.c b/MdeModulePkg/Core/Dxe/SysCall/SupportedProtocols.c
index 852ec7c663..43e7e93920 100644
--- a/MdeModulePkg/Core/Dxe/SysCall/SupportedProtocols.c
+++ b/MdeModulePkg/Core/Dxe/SysCall/SupportedProtocols.c
@@ -360,7 +360,7 @@ CoreFileSetPosition (
            File->Ring3File,
            Position
            );
-#elif defined (MDE_CPU_IA32)
+#elif defined (MDE_CPU_IA32) || defined (MDE_CPU_ARM)
   //
   // UINT64 Position is passed as 2 double words on stack.
   //
@@ -370,13 +370,6 @@ CoreFileSetPosition (
            File->Ring3File,
            Position
            );
-#else
-  return GoToRing3 (
-           2,
-           (VOID *)mRing3FileProtocol.SetPosition,
-           File->Ring3File,
-           Position
-           );
 #endif
 
 }
@@ -643,7 +636,7 @@ CoreFileOpen (
              OpenMode,
              Attributes
              );
-#elif defined (MDE_CPU_IA32)
+#elif defined (MDE_CPU_IA32) || defined (MDE_CPU_ARM)
   //
   // UINT64 OpenMode and Attributes are each passed as 2 double words on stack.
   //
@@ -656,16 +649,6 @@ CoreFileOpen (
              OpenMode,
              Attributes
              );
-#else
-  Status = GoToRing3 (
-             5,
-             (VOID *)mRing3FileProtocol.Open,
-             File->Ring3File,
-             Ring3NewHandle,
-             Ring3FileName,
-             OpenMode,
-             Attributes
-             );
 #endif
   if (EFI_ERROR (Status)) {
     *NewHandle = NULL;