UefiCpuPkg/PiSmmCpuDxeSmm: patch "gSmbase" with PatchInstructionX86()

Rename the variable to "gPatchSmbase" so that its association with
PatchInstructionX86() is clear from the declaration, change its type to
X86_ASSEMBLY_PATCH_LABEL, and patch it with PatchInstructionX86(). This
lets us remove the binary (DB) encoding of some instructions in
"SmiEntry.nasm".

Cc: Eric Dong <eric.dong@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=866
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm
index a8324a7f4a841e964c41be2dc2ad9cb9a4d6467f..e6e29128e64eb9ebb40094f632e75f259091e33b 100644 (file)
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmiEntry.nasm
@@ -46,7 +46,7 @@ global ASM_PFX(gcSmiHandlerTemplate)
 global ASM_PFX(gcSmiHandlerSize)\r
 global ASM_PFX(gSmiCr3)\r
 global ASM_PFX(gSmiStack)\r
 global ASM_PFX(gcSmiHandlerSize)\r
 global ASM_PFX(gSmiCr3)\r
 global ASM_PFX(gSmiStack)\r

-global ASM_PFX(gSmbase)\r
+global ASM_PFX(gPatchSmbase)\r

 global ASM_PFX(mXdSupported)\r
 extern ASM_PFX(gSmiHandlerIdtr)\r
 \r
 global ASM_PFX(mXdSupported)\r
 extern ASM_PFX(gSmiHandlerIdtr)\r
 \r


@@ -65,8 +65,8 @@ _SmiEntryPoint:
 o32 lgdt    [cs:bx]                       ; lgdt fword ptr cs:[bx]\r
     mov     ax, PROTECT_MODE_CS\r
     mov     [cs:bx-0x2],ax\r
 o32 lgdt    [cs:bx]                       ; lgdt fword ptr cs:[bx]\r
     mov     ax, PROTECT_MODE_CS\r
     mov     [cs:bx-0x2],ax\r

-    DB      0x66, 0xbf                   ; mov edi, SMBASE\r
-ASM_PFX(gSmbase): DD 0\r
+    mov     edi, strict dword 0           ; source operand will be patched\r
+ASM_PFX(gPatchSmbase):\r

     lea     eax, [edi + (@32bit - _SmiEntryPoint) + 0x8000]\r
     mov     [cs:bx-0x6],eax\r
     mov     ebx, cr0\r
     lea     eax, [edi + (@32bit - _SmiEntryPoint) + 0x8000]\r
     mov     [cs:bx-0x6],eax\r
     mov     ebx, cr0\r

diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c b/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c
index 3188d438181ccbed40e9d981e62dd4b8dfe792a9..d34345d5ff8034515165fd782c10402a69f88cea 100644 (file)
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/SmramSaveState.c
@@ -105,11 +105,11 @@ typedef struct {
 ///\r
 /// Variables from SMI Handler\r
 ///\r
 ///\r
 /// Variables from SMI Handler\r
 ///\r

-extern UINT32           gSmbase;\r
-extern volatile UINT32  gSmiStack;\r
-extern UINT32           gSmiCr3;\r
-extern volatile UINT8   gcSmiHandlerTemplate[];\r
-extern CONST UINT16     gcSmiHandlerSize;\r
+X86_ASSEMBLY_PATCH_LABEL gPatchSmbase;\r
+extern volatile UINT32   gSmiStack;\r
+extern UINT32            gSmiCr3;\r
+extern volatile UINT8    gcSmiHandlerTemplate[];\r
+extern CONST UINT16      gcSmiHandlerSize;\r

 \r
 //\r
 // Variables used by SMI Handler\r
 \r
 //\r
 // Variables used by SMI Handler\r


@@ -718,7 +718,7 @@ InstallSmiHandler (
   //\r
   gSmiStack             = (UINT32)((UINTN)SmiStack + StackSize - sizeof (UINTN));\r
   gSmiCr3               = Cr3;\r
   //\r
   gSmiStack             = (UINT32)((UINTN)SmiStack + StackSize - sizeof (UINTN));\r
   gSmiCr3               = Cr3;\r

-  gSmbase               = SmBase;\r
+  PatchInstructionX86 (gPatchSmbase, SmBase, 4);\r

   gSmiHandlerIdtr.Base  = IdtBase;\r
   gSmiHandlerIdtr.Limit = (UINT16)(IdtSize - 1);\r
 \r
   gSmiHandlerIdtr.Base  = IdtBase;\r
   gSmiHandlerIdtr.Limit = (UINT16)(IdtSize - 1);\r
 \r

diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm
index 697fd2bec7c616c8d1fd855dd3afccf4f846afcb..0e314279a54136883526bdc34f66ff3206a8bfb3 100644 (file)
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmiEntry.nasm
@@ -53,7 +53,7 @@ extern ASM_PFX(gSmiHandlerIdtr)
 extern ASM_PFX(CpuSmmDebugEntry)\r
 extern ASM_PFX(CpuSmmDebugExit)\r
 \r
 extern ASM_PFX(CpuSmmDebugEntry)\r
 extern ASM_PFX(CpuSmmDebugExit)\r
 \r

-global ASM_PFX(gSmbase)\r
+global ASM_PFX(gPatchSmbase)\r

 global ASM_PFX(mXdSupported)\r
 global ASM_PFX(gSmiStack)\r
 global ASM_PFX(gSmiCr3)\r
 global ASM_PFX(mXdSupported)\r
 global ASM_PFX(gSmiStack)\r
 global ASM_PFX(gSmiCr3)\r


@@ -75,8 +75,8 @@ _SmiEntryPoint:
 o32 lgdt    [cs:bx]                       ; lgdt fword ptr cs:[bx]\r
     mov     ax, PROTECT_MODE_CS\r
     mov     [cs:bx-0x2],ax\r
 o32 lgdt    [cs:bx]                       ; lgdt fword ptr cs:[bx]\r
     mov     ax, PROTECT_MODE_CS\r
     mov     [cs:bx-0x2],ax\r

-    DB      0x66, 0xbf                   ; mov edi, SMBASE\r
-ASM_PFX(gSmbase): DD 0\r
+    mov     edi, strict dword 0           ; source operand will be patched\r
+ASM_PFX(gPatchSmbase):\r

     lea     eax, [edi + (@ProtectedMode - _SmiEntryPoint) + 0x8000]\r
     mov     [cs:bx-0x6],eax\r
     mov     ebx, cr0\r
     lea     eax, [edi + (@ProtectedMode - _SmiEntryPoint) + 0x8000]\r
     mov     [cs:bx-0x6],eax\r
     mov     ebx, cr0\r