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>
This commit is contained in:
Laszlo Ersek 2018-02-01 23:01:08 +01:00
parent 38a5df04ef
commit 5a1bfda4bd
3 changed files with 12 additions and 12 deletions

View File

@ -46,7 +46,7 @@ global ASM_PFX(gcSmiHandlerTemplate)
global ASM_PFX(gcSmiHandlerSize)
global ASM_PFX(gSmiCr3)
global ASM_PFX(gSmiStack)
global ASM_PFX(gSmbase)
global ASM_PFX(gPatchSmbase)
global ASM_PFX(mXdSupported)
extern ASM_PFX(gSmiHandlerIdtr)
@ -65,8 +65,8 @@ _SmiEntryPoint:
o32 lgdt [cs:bx] ; lgdt fword ptr cs:[bx]
mov ax, PROTECT_MODE_CS
mov [cs:bx-0x2],ax
DB 0x66, 0xbf ; mov edi, SMBASE
ASM_PFX(gSmbase): DD 0
mov edi, strict dword 0 ; source operand will be patched
ASM_PFX(gPatchSmbase):
lea eax, [edi + (@32bit - _SmiEntryPoint) + 0x8000]
mov [cs:bx-0x6],eax
mov ebx, cr0

View File

@ -105,7 +105,7 @@ typedef struct {
///
/// Variables from SMI Handler
///
extern UINT32 gSmbase;
X86_ASSEMBLY_PATCH_LABEL gPatchSmbase;
extern volatile UINT32 gSmiStack;
extern UINT32 gSmiCr3;
extern volatile UINT8 gcSmiHandlerTemplate[];
@ -718,7 +718,7 @@ InstallSmiHandler (
//
gSmiStack = (UINT32)((UINTN)SmiStack + StackSize - sizeof (UINTN));
gSmiCr3 = Cr3;
gSmbase = SmBase;
PatchInstructionX86 (gPatchSmbase, SmBase, 4);
gSmiHandlerIdtr.Base = IdtBase;
gSmiHandlerIdtr.Limit = (UINT16)(IdtSize - 1);

View File

@ -53,7 +53,7 @@ extern ASM_PFX(gSmiHandlerIdtr)
extern ASM_PFX(CpuSmmDebugEntry)
extern ASM_PFX(CpuSmmDebugExit)
global ASM_PFX(gSmbase)
global ASM_PFX(gPatchSmbase)
global ASM_PFX(mXdSupported)
global ASM_PFX(gSmiStack)
global ASM_PFX(gSmiCr3)
@ -75,8 +75,8 @@ _SmiEntryPoint:
o32 lgdt [cs:bx] ; lgdt fword ptr cs:[bx]
mov ax, PROTECT_MODE_CS
mov [cs:bx-0x2],ax
DB 0x66, 0xbf ; mov edi, SMBASE
ASM_PFX(gSmbase): DD 0
mov edi, strict dword 0 ; source operand will be patched
ASM_PFX(gPatchSmbase):
lea eax, [edi + (@ProtectedMode - _SmiEntryPoint) + 0x8000]
mov [cs:bx-0x6],eax
mov ebx, cr0