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UefiCpuPkg/PiSmmCpuDxeSmm: patch "gSmmCr3" with PatchInstructionX86()

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Rename the variable to "gPatchSmmCr3" 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
"SmmInit.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
2018-02-02 01:48:56 +01:00
parent 00c5eede48
commit 6b0841c166
4 changed files with 8 additions and 8 deletions
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6
UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmInit.nasm
View File

@@ -22,7 +22,7 @@ extern ASM_PFX(SmmInitHandler)
extern ASM_PFX(mRebasedFlag)
extern ASM_PFX(mSmmRelocationOriginalAddress)
global ASM_PFX(gSmmCr3)
global ASM_PFX(gPatchSmmCr3)
global ASM_PFX(gSmmCr4)
global ASM_PFX(gSmmCr0)
global ASM_PFX(gSmmJmpAddr)
@@ -47,8 +47,8 @@ ASM_PFX(SmmStartup):
mov eax, 0x80000001 ; read capability
cpuid
mov ebx, edx ; rdmsr will change edx. keep it in ebx.
DB 0x66, 0xb8 ; mov eax, imm32
ASM_PFX(gSmmCr3): DD 0
mov eax, strict dword 0 ; source operand will be patched
ASM_PFX(gPatchSmmCr3):
mov cr3, eax
o32 lgdt [cs:ebp + (ASM_PFX(gcSmiInitGdtr) - ASM_PFX(SmmStartup))]
DB 0x66, 0xb8 ; mov eax, imm32