tyler.durden
/
audk
mirror of https://github.com/acidanthera/audk.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

UefiCpuPkg/PiSmmCpuDxeSmm: remove DBs from SmmRelocationSemaphoreComplete32() 

(1) SmmRelocationSemaphoreComplete32() runs in 32-bit mode, so wrap it in
    a (BITS 32 ... BITS 64) bracket.

(2) SmmRelocationSemaphoreComplete32() currently compiles to:

> 000002AE  C6050000000001    mov byte [dword 0x0],0x1
> 000002B5  FF2500000000      jmp dword [dword 0x0]

    where the first instruction is patched with the contents of
    "mRebasedFlag" (so that (*mRebasedFlag) is set to 1), and the second
    instruction is patched with the address of
    "mSmmRelocationOriginalAddress" (so that we jump to
    "mSmmRelocationOriginalAddress").

    In its current form the first instruction could not be patched with
    PatchInstructionX86(), given that the operand to patch is not encoded
    in the trailing bytes of the instruction. Therefore, adopt an
    EAX-based version, inspired by both the IA32 and X64 variants of
    SmmRelocationSemaphoreComplete():

> 000002AE  50                push eax
> 000002AF  B800000000        mov eax,0x0
> 000002B4  C60001            mov byte [eax],0x1
> 000002B7  58                pop eax
> 000002B8  FF2500000000      jmp dword [dword 0x0]

    Here both instructions can be patched with PatchInstructionX86(), and
    the DBs can be replaced with native NASM syntax.

(3) Turn the "mRebasedFlagAddr32" and "mSmmRelocationOriginalAddressPtr32"
    variables into markers that suit PatchInstructionX86().

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 05:36:22 +01:00
parent 5830d2c399
commit 9686a4678d
2 changed files with 23 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
UefiCpuPkg/PiSmmCpuDxeSmm/X64/Semaphore.c
View File

@ -15,8 +15,8 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#include "PiSmmCpuDxeSmm.h"
extern UINT32 mSmmRelocationOriginalAddressPtr32;
extern UINT32 mRebasedFlagAddr32;
X86_ASSEMBLY_PATCH_LABEL gPatchSmmRelocationOriginalAddressPtr32;
X86_ASSEMBLY_PATCH_LABEL gPatchRebasedFlagAddr32;
UINTN mSmmRelocationOriginalAddress;
volatile BOOLEAN *mRebasedFlag;
@ -49,7 +49,11 @@ SemaphoreHook (
UINTN TempValue;
mRebasedFlag = RebasedFlag;
mRebasedFlagAddr32 = (UINT32)(UINTN)mRebasedFlag;
PatchInstructionX86 (
gPatchRebasedFlagAddr32,
(UINT32)(UINTN)mRebasedFlag,
4
);
CpuState = (SMRAM_SAVE_STATE_MAP *)(UINTN)(SMM_DEFAULT_SMBASE + SMRAM_SAVE_STATE_MAP_OFFSET);
mSmmRelocationOriginalAddress = HookReturnFromSmm (
@ -63,5 +67,9 @@ SemaphoreHook (
// Use temp value to fix ICC complier warning
//
TempValue = (UINTN)&mSmmRelocationOriginalAddress;
mSmmRelocationOriginalAddressPtr32 = (UINT32)TempValue;
PatchInstructionX86 (
gPatchSmmRelocationOriginalAddressPtr32,
(UINT32)TempValue,
4
);
}

24
UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmInit.nasm
View File

@ -29,8 +29,8 @@ global ASM_PFX(gPatchSmmInitStack)
global ASM_PFX(gcSmiInitGdtr)
global ASM_PFX(gcSmmInitSize)
global ASM_PFX(gcSmmInitTemplate)
global ASM_PFX(mRebasedFlagAddr32)
global ASM_PFX(mSmmRelocationOriginalAddressPtr32)
global ASM_PFX(gPatchRebasedFlagAddr32)
global ASM_PFX(gPatchSmmRelocationOriginalAddressPtr32)
%define LONG_MODE_CS 0x38
@ -125,20 +125,18 @@ ASM_PFX(SmmRelocationSemaphoreComplete):
;
; Semaphore code running in 32-bit mode
;
BITS 32
global ASM_PFX(SmmRelocationSemaphoreComplete32)
ASM_PFX(SmmRelocationSemaphoreComplete32):
;
; mov byte ptr [], 1
;
db 0xc6, 0x5
ASM_PFX(mRebasedFlagAddr32): dd 0
db 1
;
; jmp dword ptr []
;
db 0xff, 0x25
ASM_PFX(mSmmRelocationOriginalAddressPtr32): dd 0
push eax
mov eax, strict dword 0 ; source operand will be patched
ASM_PFX(gPatchRebasedFlagAddr32):
mov byte [eax], 1
pop eax
jmp dword [dword 0] ; destination will be patched
ASM_PFX(gPatchSmmRelocationOriginalAddressPtr32):
BITS 64
global ASM_PFX(PiSmmCpuSmmInitFixupAddress)
ASM_PFX(PiSmmCpuSmmInitFixupAddress):
lea rax, [@LongMode]