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|
;------------------------------------------------------------------------------ ;
; Copyright (c) 2009 - 2016, 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.nasm
;
; Abstract:
;
; Exception handlers used in SM mode
;
;-------------------------------------------------------------------------------
global ASM_PFX(gcStmPsd)
extern ASM_PFX(SmmStmExceptionHandler)
extern ASM_PFX(SmmStmSetup)
extern ASM_PFX(SmmStmTeardown)
extern ASM_PFX(gStmXdSupported)
extern ASM_PFX(gStmSmiHandlerIdtr)
%define MSR_IA32_MISC_ENABLE 0x1A0
%define MSR_EFER 0xc0000080
%define MSR_EFER_XD 0x800
CODE_SEL equ 0x08
DATA_SEL equ 0x20
TSS_SEL equ 0x40
SECTION .data
ASM_PFX(gcStmPsd):
DB 'TXTPSSIG'
DW PSD_SIZE
DW 1 ; Version
DD 0 ; LocalApicId
DB 0x05 ; 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
DD ASM_PFX(OnStmSetup)
DD 0
DD ASM_PFX(OnStmTeardown)
DD 0
DQ 0 ; SmmSmiHandlerRip - SMM guest entrypoint
DQ 0 ; SmmSmiHandlerRsp
DQ 0
DD 0
DD 0x80010100 ; RequiredStmSmmRevId
DD ASM_PFX(OnException)
DD 0
DQ 0 ; ExceptionStack
DW DATA_SEL
DW 0x01F ; ExceptionFilter
DD 0
DD 0
DD 0
DQ 0 ; BiosHwResourceRequirementsPtr
DQ 0 ; AcpiRsdp
DB 0 ; PhysicalAddressBits
PSD_SIZE equ $ - ASM_PFX(gcStmPsd)
SECTION .text
;------------------------------------------------------------------------------
; SMM Exception handlers
;------------------------------------------------------------------------------
global ASM_PFX(OnException)
ASM_PFX(OnException):
mov ecx, esp
push ecx
call ASM_PFX(SmmStmExceptionHandler)
add esp, 4
mov ebx, eax
mov eax, 4
DB 0x0f, 0x01, 0x0c1 ; VMCALL
jmp $
global ASM_PFX(OnStmSetup)
ASM_PFX(OnStmSetup):
;
; Check XD disable bit
;
xor esi, esi
mov eax, ASM_PFX(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 .51
and dx, 0xFFFB ; clear XD Disable bit if it is set
wrmsr
.51:
mov ecx, MSR_EFER
rdmsr
or ax, MSR_EFER_XD ; enable NXE
wrmsr
@StmXdDone1:
push esi
call ASM_PFX(SmmStmSetup)
mov eax, ASM_PFX(gStmXdSupported)
mov al, [eax]
cmp al, 0
jz .71
pop edx ; get saved MSR_IA32_MISC_ENABLE[63-32]
test edx, BIT2
jz .71
mov ecx, MSR_IA32_MISC_ENABLE
rdmsr
or dx, BIT2 ; set XD Disable bit if it was set before entering into SMM
wrmsr
.71:
rsm
global ASM_PFX(OnStmTeardown)
ASM_PFX(OnStmTeardown):
;
; Check XD disable bit
;
xor esi, esi
mov eax, ASM_PFX(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 .52
and dx, 0xFFFB ; clear XD Disable bit if it is set
wrmsr
.52:
mov ecx, MSR_EFER
rdmsr
or ax, MSR_EFER_XD ; enable NXE
wrmsr
@StmXdDone2:
push esi
call ASM_PFX(SmmStmTeardown)
mov eax, ASM_PFX(gStmXdSupported)
mov al, [eax]
cmp al, 0
jz .72
pop edx ; get saved MSR_IA32_MISC_ENABLE[63-32]
test edx, BIT2
jz .72
mov ecx, MSR_IA32_MISC_ENABLE
rdmsr
or dx, BIT2 ; set XD Disable bit if it was set before entering into SMM
wrmsr
.72:
rsm
|
