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|
;------------------------------------------------------------------------------ ;
; Copyright (c) 2009 - 2017, Intel Corporation. All rights reserved.<BR>
; This program and the accompanying materials
; are licensed and made available under the terms and conditions of the BSD License
; which accompanies this distribution. The full text of the license may be found at
; http://opensource.org/licenses/bsd-license.php.
;
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
;
; Module Name:
;
; SmiException.asm
;
; Abstract:
;
; Exception handlers used in SM mode
;
;-------------------------------------------------------------------------------
.686p
.model flat,C
EXTERNDEF gcStmPsd:BYTE
EXTERNDEF SmmStmExceptionHandler:PROC
EXTERNDEF SmmStmSetup:PROC
EXTERNDEF SmmStmTeardown:PROC
EXTERNDEF gStmXdSupported:BYTE
CODE_SEL = 08h
DATA_SEL = 20h
TSS_SEL = 40h
MSR_IA32_MISC_ENABLE EQU 1A0h
MSR_EFER EQU 0c0000080h
MSR_EFER_XD EQU 0800h
.data
gcStmPsd LABEL BYTE
DB 'TXTPSSIG'
DW PSD_SIZE
DW 1 ; Version
DD 0 ; LocalApicId
DB 05h ; Cr4Pse;Cr4Pae;Intel64Mode;ExecutionDisableOutsideSmrr
DB 0 ; BIOS to STM
DB 0 ; STM to BIOS
DB 0
DW CODE_SEL
DW DATA_SEL
DW DATA_SEL
DW DATA_SEL
DW TSS_SEL
DW 0
DQ 0 ; SmmCr3
DQ _OnStmSetup
DQ _OnStmTeardown
DQ 0 ; SmmSmiHandlerRip - SMM guest entrypoint
DQ 0 ; SmmSmiHandlerRsp
DQ 0
DD 0
DD 80010100h ; RequiredStmSmmRevId
DQ _OnException
DQ 0 ; ExceptionStack
DW DATA_SEL
DW 01Fh ; ExceptionFilter
DD 0
DQ 0
DQ 0 ; BiosHwResourceRequirementsPtr
DQ 0 ; AcpiRsdp
DB 0 ; PhysicalAddressBits
PSD_SIZE = $ - offset gcStmPsd
.code
;------------------------------------------------------------------------------
; SMM Exception handlers
;------------------------------------------------------------------------------
_OnException PROC
mov ecx, esp
push ecx
call SmmStmExceptionHandler
add esp, 4
mov ebx, eax
mov eax, 4
DB 0fh, 01h, 0c1h ; VMCALL
jmp $
_OnException ENDP
_OnStmSetup PROC
;
; Check XD disable bit
;
xor esi, esi
mov eax, offset gStmXdSupported
mov al, [eax]
cmp al, 0
jz @StmXdDone1
mov ecx, MSR_IA32_MISC_ENABLE
rdmsr
mov esi, edx ; save MSR_IA32_MISC_ENABLE[63-32]
test edx, BIT2 ; MSR_IA32_MISC_ENABLE[34]
jz @f
and dx, 0FFFBh ; clear XD Disable bit if it is set
wrmsr
@@:
mov ecx, MSR_EFER
rdmsr
or ax, MSR_EFER_XD ; enable NXE
wrmsr
@StmXdDone1:
push esi
call SmmStmSetup
mov eax, offset gStmXdSupported
mov al, [eax]
cmp al, 0
jz @f
pop edx ; get saved MSR_IA32_MISC_ENABLE[63-32]
test edx, BIT2
jz @f
mov ecx, MSR_IA32_MISC_ENABLE
rdmsr
or dx, BIT2 ; set XD Disable bit if it was set before entering into SMM
wrmsr
@@:
rsm
_OnStmSetup ENDP
_OnStmTeardown PROC
;
; Check XD disable bit
;
xor esi, esi
mov eax, offset gStmXdSupported
mov al, [eax]
cmp al, 0
jz @StmXdDone2
mov ecx, MSR_IA32_MISC_ENABLE
rdmsr
mov esi, edx ; save MSR_IA32_MISC_ENABLE[63-32]
test edx, BIT2 ; MSR_IA32_MISC_ENABLE[34]
jz @f
and dx, 0FFFBh ; clear XD Disable bit if it is set
wrmsr
@@:
mov ecx, MSR_EFER
rdmsr
or ax, MSR_EFER_XD ; enable NXE
wrmsr
@StmXdDone2:
push esi
call SmmStmTeardown
mov eax, offset gStmXdSupported
mov al, [eax]
cmp al, 0
jz @f
pop edx ; get saved MSR_IA32_MISC_ENABLE[63-32]
test edx, BIT2
jz @f
mov ecx, MSR_IA32_MISC_ENABLE
rdmsr
or dx, BIT2 ; set XD Disable bit if it was set before entering into SMM
wrmsr
@@:
rsm
_OnStmTeardown ENDP
END
|
