sravan/system76-edk2
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

MdeModulePkg: Remove X86 ASM and S files

Browse Source 
NASM has replaced ASM and S files.
1. Remove ASM from all modules.
2. Remove S files from the drivers only.
3. https://bugzilla.tianocore.org/show_bug.cgi?id=881
After NASM is updated, S files can be removed from Library.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
This commit is contained in:
Liming Gao
2018-06-04 13:35:58 +08:00
parent 13688930ae
commit 6d614649ab
22 changed files with 6 additions and 3510 deletions
Download Patch File Download Diff File Expand all files Collapse all files

551
MdeModulePkg/Universal/DebugSupportDxe/X64/AsmFuncs.S
View File

@@ -1,551 +0,0 @@
///**@file
// Low leve x64 specific debug support functions.
//
// Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
// Portions copyright (c) 2008 - 2009, Apple Inc. 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.
//
//**/
ASM_GLOBAL ASM_PFX(OrigVector)
ASM_GLOBAL ASM_PFX(InterruptEntryStub)
ASM_GLOBAL ASM_PFX(StubSize)
ASM_GLOBAL ASM_PFX(CommonIdtEntry)
ASM_GLOBAL ASM_PFX(FxStorSupport)
.data
ASM_PFX(StubSize): .long ASM_PFX(InterruptEntryStubEnd) - ASM_PFX(InterruptEntryStub)
ASM_PFX(AppRsp): .long 0x11111111 # ?
.long 0x11111111 # ?
ASM_PFX(DebugRsp): .long 0x22222222 # ?
.long 0x22222222 # ?
ASM_PFX(ExtraPush): .long 0x33333333 # ?
.long 0x33333333 # ?
ASM_PFX(ExceptData): .long 0x44444444 # ?
.long 0x44444444 # ?
ASM_PFX(Rflags): .long 0x55555555 # ?
.long 0x55555555 # ?
ASM_PFX(OrigVector): .long 0x66666666 # ?
.long 0x66666666 # ?
// The declarations below define the memory region that will be used for the debug stack.
// The context record will be built by pushing register values onto this stack.
// It is imparitive that alignment be carefully managed, since the FXSTOR and
// FXRSTOR instructions will GP fault if their memory operand is not 16 byte aligned.
//
// The stub will switch stacks from the application stack to the debuger stack
// and pushes the exception number.
//
// Then we building the context record on the stack. Since the stack grows down,
// we push the fields of the context record from the back to the front. There
// are 336 bytes of stack used prior allocating the 512 bytes of stack to be
// used as the memory buffer for the fxstor instruction. Therefore address of
// the buffer used for the FXSTOR instruction is &Eax - 336 - 512, which
// must be 16 byte aligned.
//
// We carefully locate the stack to make this happen.
//
// For reference, the context structure looks like this:
// struct {
// UINT64 ExceptionData;
// FX_SAVE_STATE_X64 FxSaveState; // 512 bytes, must be 16 byte aligned
// UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
// UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;
// UINT64 RFlags;
// UINT64 Ldtr, Tr;
// UINT64 Gdtr[2], Idtr[2];
// UINT64 Rip;
// UINT64 Gs, Fs, Es, Ds, Cs, Ss;
// UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
// UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
// } SYSTEM_CONTEXT_X64; // 64 bit system context record
.p2align 4
DebugStackEnd : .ascii "DbgStkEnd >>>>>>" # 16 byte long string - must be 16 bytes to preserve alignment
.fill 0x1ffc, 4, 0x00000000
# 32K should be enough stack
# This allocation is coocked to insure
# that the the buffer for the FXSTORE instruction
# will be 16 byte aligned also.
#
ASM_PFX(ExceptionNumber): .long 0x77777777 # first entry will be the vector number pushed by the stub
.long 0x77777777 # ?
DebugStackBegin : .ascii "<<<< DbgStkBegin" # initial debug ESP == DebugStackBegin, set in stub
.text
//------------------------------------------------------------------------------
// BOOLEAN
// FxStorSupport (
// void
// )
//
// Abstract: Returns TRUE if FxStor instructions are supported
//
ASM_GLOBAL ASM_PFX(FxStorSupport)
ASM_PFX(FxStorSupport):
//
// cpuid corrupts rbx which must be preserved per the C calling convention
//
pushq %rbx
movq $1, %rax
cpuid
movl %edx, %eax
andq $0x01000000, %rax
shrq $24, %rax
popq %rbx
ret
//------------------------------------------------------------------------------
// void
// Vect2Desc (
// IA32_IDT_GATE_DESCRIPTOR * DestDesc, // rcx
// void (*Vector) (void) // rdx
// )
//
// Abstract: Encodes an IDT descriptor with the given physical address
//
ASM_GLOBAL ASM_PFX(Vect2Desc)
ASM_PFX(Vect2Desc):
movq %rdx, %rax
movw %ax, (%rcx) # write bits 15..0 of offset
movw %cs, %dx
movw %dx, 2(%rcx) # SYS_CODE_SEL from GDT
movw $(0x0e00 | 0x8000), 4(%rcx) # type = 386 interrupt gate, present
shrq $16, %rax
movw %ax, 6(%rcx) # write bits 31..16 of offset
shrq $16, %rax
movl %eax, 8(%rcx) # write bits 63..32 of offset
ret
//------------------------------------------------------------------------------
// InterruptEntryStub
//
// Abstract: This code is not a function, but is a small piece of code that is
// copied and fixed up once for each IDT entry that is hooked.
//
ASM_GLOBAL ASM_PFX(InterruptEntryStub)
ASM_PFX(InterruptEntryStub):
pushq $0 # push vector number - will be modified before installed
jmp ASM_PFX(CommonIdtEntry)
ASM_GLOBAL ASM_PFX(InterruptEntryStubEnd)
ASM_PFX(InterruptEntryStubEnd):
//------------------------------------------------------------------------------
// CommonIdtEntry
//
// Abstract: This code is not a function, but is the common part for all IDT
// vectors.
//
ASM_GLOBAL ASM_PFX(CommonIdtEntry)
//
// At this point, the stub has saved the current application stack esp into AppRsp
// and switched stacks to the debug stack, where it pushed the vector number
//
// The application stack looks like this:
//
// ...
// (last application stack entry)
// [16 bytes alignment, do not care it]
// SS from interrupted task
// RSP from interrupted task
// rflags from interrupted task
// CS from interrupted task
// RIP from interrupted task
// Error code <-------------------- Only present for some exeption types
//
// Vector Number <----------------- pushed in our IDT Entry
//
// The stub switched us to the debug stack and pushed the interrupt number.
//
// Next, construct the context record. It will be build on the debug stack by
// pushing the registers in the correct order so as to create the context structure
// on the debug stack. The context record must be built from the end back to the
// beginning because the stack grows down...
//
// For reference, the context record looks like this:
//
// typedef
// struct {
// UINT64 ExceptionData;
// FX_SAVE_STATE_X64 FxSaveState;
// UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
// UINT64 Cr0, Cr2, Cr3, Cr4, Cr8;
// UINT64 RFlags;
// UINT64 Ldtr, Tr;
// UINT64 Gdtr[2], Idtr[2];
// UINT64 Rip;
// UINT64 Gs, Fs, Es, Ds, Cs, Ss;
// UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
// UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
// } SYSTEM_CONTEXT_X64; // 64
ASM_PFX(CommonIdtEntry):
// NOTE: we save rsp here to prevent compiler put rip reference cause error AppRsp
pushq %rax
movq (8)(%rsp), %rax # save vector number
movq %rax, ASM_PFX(ExceptionNumber)(%rip) # save vector number
popq %rax
addq $8, %rsp # pop vector number
movq %rsp, ASM_PFX(AppRsp)(%rip) # save stack top
movq DebugStackBegin(%rip), %rsp # switch to debugger stack
subq $8, %rsp # leave space for vector number
// UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
// UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
pushq %r15
pushq %r14
pushq %r13
pushq %r12
pushq %r11
pushq %r10
pushq %r9
pushq %r8
pushq %rax
pushq %rcx
pushq %rdx
pushq %rbx
pushq %rsp
pushq %rbp
pushq %rsi
pushq %rdi
// Save interrupt state rflags register...
pushfq
popq %rax
movq %rax, ASM_PFX(Rflags)(%rip)
// We need to determine if any extra data was pushed by the exception, and if so, save it
// To do this, we check the exception number pushed by the stub, and cache the
// result in a variable since we'll need this again.
cmpl $0, ASM_PFX(ExceptionNumber)(%rip)
jz ExtraPushOne
cmpl $10, ASM_PFX(ExceptionNumber)(%rip)
jz ExtraPushOne
cmpl $11, ASM_PFX(ExceptionNumber)(%rip)
jz ExtraPushOne
cmpl $12, ASM_PFX(ExceptionNumber)(%rip)
jz ExtraPushOne
cmpl $13, ASM_PFX(ExceptionNumber)(%rip)
jz ExtraPushOne
cmpl $14, ASM_PFX(ExceptionNumber)(%rip)
jz ExtraPushOne
cmpl $17, ASM_PFX(ExceptionNumber)(%rip)
jz ExtraPushOne
movl $0, ASM_PFX(ExtraPush)(%rip)
movl $0, ASM_PFX(ExceptData)(%rip)
jmp ExtraPushDone
ExtraPushOne:
movl $1, ASM_PFX(ExtraPush)(%rip)
// If there's some extra data, save it also, and modify the saved AppRsp to effectively
// pop this value off the application's stack.
movq ASM_PFX(AppRsp)(%rip), %rax
movq (%rax), %rbx
movq %rbx, ASM_PFX(ExceptData)(%rip)
addq $8, %rax
movq %rax, ASM_PFX(AppRsp)(%rip)
ExtraPushDone:
// The "push" above pushed the debug stack rsp. Since what we're actually doing
// is building the context record on the debug stack, we need to save the pushed
// debug RSP, and replace it with the application's last stack entry...
movq 24(%rsp), %rax
movq %rax, ASM_PFX(DebugRsp)(%rip)
movq ASM_PFX(AppRsp)(%rip), %rax
movq 24(%rax), %rax
# application stack has ss, rsp, rflags, cs, & rip, so
# last actual application stack entry is saved at offset
# 24 bytes from stack top.
movq %rax, 24(%rsp)
// continue building context record
// UINT64 Gs, Fs, Es, Ds, Cs, Ss; insure high 16 bits of each is zero
mov %ss, %rax
pushq %rax
# CS from application is one entry back in application stack
movq ASM_PFX(AppRsp)(%rip), %rax
movzwq 8(%rax), %rax
pushq %rax
mov %ds, %rax
pushq %rax
mov %es, %rax
pushq %rax
mov %fs, %rax
pushq %rax
mov %gs, %rax
pushq %rax
// UINT64 Rip;
# Rip from application is on top of application stack
movq ASM_PFX(AppRsp)(%rip), %rax
pushq (%rax)
// UINT64 Gdtr[2], Idtr[2];
push $0
push $0
sidtq (%rsp)
push $0
push $0
sgdtq (%rsp)
// UINT64 Ldtr, Tr;
xorq %rax, %rax
str %ax
pushq %rax
sldt %ax
pushq %rax
// UINT64 RFlags;
// Rflags from application is two entries back in application stack
movq ASM_PFX(AppRsp)(%rip), %rax
pushq 16(%rax)
// UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;
// insure FXSAVE/FXRSTOR is enabled in CR4...
// ... while we're at it, make sure DE is also enabled...
movq %cr8, %rax
pushq %rax
movq %cr4, %rax
orq $0x208, %rax
movq %rax, %cr4
pushq %rax
movq %cr3, %rax
pushq %rax
movq %cr2, %rax
pushq %rax
push $0
movq %cr0, %rax
pushq %rax
// UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
movq %dr7, %rax
pushq %rax
// clear Dr7 while executing debugger itself
xorq %rax, %rax
movq %rax, %dr7
movq %dr6, %rax
pushq %rax
// insure all status bits in dr6 are clear...
xorq %rax, %rax
movq %rax, %dr6
movq %dr3, %rax
pushq %rax
movq %dr2, %rax
pushq %rax
movq %dr1, %rax
pushq %rax
movq %dr0, %rax
pushq %rax
// FX_SAVE_STATE_X64 FxSaveState;
subq $512, %rsp
movq %rsp, %rdi
# IMPORTANT!! The debug stack has been carefully constructed to
# insure that rsp and rdi are 16 byte aligned when we get here.
# They MUST be. If they are not, a GP fault will occur.
# FXSTOR_RDI
fxsave (%rdi)
// UEFI calling convention for x64 requires that Direction flag in EFLAGs is clear
cld
// UINT64 ExceptionData;
movq ASM_PFX(ExceptData)(%rip), %rax
pushq %rax
// call to C code which will in turn call registered handler
// pass in the vector number
movq %rsp, %rdx
movq ASM_PFX(ExceptionNumber)(%rip), %rcx
subq $40, %rsp
call ASM_PFX(InterruptDistrubutionHub)
addq $40, %rsp
// restore context...
// UINT64 ExceptionData;
addq $8, %rsp
// FX_SAVE_STATE_X64 FxSaveState;
movq %rsp, %rsi
# FXRSTOR_RSI
fxrstor (%rsi)
addq $512, %rsp
// UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
popq %rax
movq %rax, %dr0
popq %rax
movq %rax, %dr1
popq %rax
movq %rax, %dr2
popq %rax
movq %rax, %dr3
// skip restore of dr6. We cleared dr6 during the context save.
addq $8, %rsp
popq %rax
movq %rax, %dr7
// UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;
popq %rax
movq %rax, %cr0
addq $8, %rsp
popq %rax
movq %rax, %cr2
popq %rax
movq %rax, %cr3
popq %rax
movq %rax, %cr4
popq %rax
movq %rax, %cr8
// UINT64 RFlags;
movq ASM_PFX(AppRsp)(%rip), %rax
popq 16(%rax)
// UINT64 Ldtr, Tr;
// UINT64 Gdtr[2], Idtr[2];
// Best not let anyone mess with these particular registers...
addq $48, %rsp
// UINT64 Rip;
popq (%rax)
// UINT64 Gs, Fs, Es, Ds, Cs, Ss;
// NOTE - modified segment registers could hang the debugger... We
// could attempt to insulate ourselves against this possibility,
// but that poses risks as well.
//
popq %rax
# mov %rax, %gs
popq %rax
# mov %rax, %fs
popq %rax
mov %rax, %es
popq %rax
mov %rax, %ds
movq ASM_PFX(AppRsp)(%rip), %rax
popq 8(%rax)
popq %rax
mov %rax, %ss
## The next stuff to restore is the general purpose registers that were pushed
## using the "push" instruction.
##
## The value of RSP as stored in the context record is the application RSP
## including the 5 entries on the application stack caused by the exception
## itself. It may have been modified by the debug agent, so we need to
## determine if we need to relocate the application stack.
movq 24(%rsp), %rbx # move the potentially modified AppRsp into rbx
movq ASM_PFX(AppRsp)(%rip), %rax
movq 24(%rax), %rax
cmpq %rax, %rbx
je NoAppStackMove
movq ASM_PFX(AppRsp)(%rip), %rax
movq (%rax), %rcx # RIP
movq %rcx, (%rbx)
movq 8(%rax), %rcx # CS
movq %rcx, 8(%rbx)
movq 16(%rax), %rcx # RFLAGS
movq %rcx, 16(%rbx)
movq 24(%rax), %rcx # RSP
movq %rcx, 24(%rbx)
movq 32(%rax), %rcx # SS
movq %rcx, 32(%rbx)
movq %rbx, %rax # modify the saved AppRsp to the new AppRsp
movq %rax, ASM_PFX(AppRsp)(%rip)
NoAppStackMove:
movq ASM_PFX(DebugRsp)(%rip), %rax # restore the DebugRsp on the debug stack
# so our "pop" will not cause a stack switch
movq %rax, 24(%rsp)
cmpl $0x068, ASM_PFX(ExceptionNumber)(%rip)
jne NoChain
Chain:
// Restore rflags so when we chain, the flags will be exactly as if we were never here.
// We gin up the stack to do an iretq so we can get ALL the flags.
movq ASM_PFX(AppRsp)(%rip), %rax
movq 40(%rax), %rbx
pushq %rbx
mov %ss, %rax
pushq %rax
movq %rsp, %rax
addq $16, %rax
pushq %rax
movq ASM_PFX(AppRsp)(%rip), %rax
movq 16(%rax), %rbx
andq $0xfffffffffffffcff, %rbx # special handling for IF and TF
pushq %rbx
mov %cs, %rax
pushq %rax
movq PhonyIretq(%rip), %rax
pushq %rax
iretq
PhonyIretq:
// UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
// UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
popq %rdi
popq %rsi
popq %rbp
popq %rsp
popq %rbx
popq %rdx
popq %rcx
popq %rax
popq %r8
popq %r9
popq %r10
popq %r11
popq %r12
popq %r13
popq %r14
popq %r15
// Switch back to application stack
movq ASM_PFX(AppRsp)(%rip), %rsp
// Jump to original handler
jmp ASM_PFX(OrigVector)
NoChain:
// UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
// UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
popq %rdi
popq %rsi
popq %rbp
popq %rsp
popq %rbx
popq %rdx
popq %rcx
popq %rax
popq %r8
popq %r9
popq %r10
popq %r11
popq %r12
popq %r13
popq %r14
popq %r15
// Switch back to application stack
movq ASM_PFX(AppRsp)(%rip), %rsp
// We're outa here...
iret

596
MdeModulePkg/Universal/DebugSupportDxe/X64/AsmFuncs.asm
View File

@@ -1,596 +0,0 @@
;/** @file
; Low level x64 routines used by the debug support driver.
;
; Copyright (c) 2007 - 2011, 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.
;
;**/
EXCPT64_DIVIDE_ERROR EQU 0
EXCPT64_DEBUG EQU 1
EXCPT64_NMI EQU 2
EXCPT64_BREAKPOINT EQU 3
EXCPT64_OVERFLOW EQU 4
EXCPT64_BOUND EQU 5
EXCPT64_INVALID_OPCODE EQU 6
EXCPT64_DOUBLE_FAULT EQU 8
EXCPT64_INVALID_TSS EQU 10
EXCPT64_SEG_NOT_PRESENT EQU 11
EXCPT64_STACK_FAULT EQU 12
EXCPT64_GP_FAULT EQU 13
EXCPT64_PAGE_FAULT EQU 14
EXCPT64_FP_ERROR EQU 16
EXCPT64_ALIGNMENT_CHECK EQU 17
EXCPT64_MACHINE_CHECK EQU 18
EXCPT64_SIMD EQU 19
FXSTOR_FLAG EQU 01000000h ; bit cpuid 24 of feature flags
;; The FXSTOR and FXRSTOR commands are used for saving and restoring the x87,
;; MMX, SSE, SSE2, etc registers. The initialization of the debugsupport driver
;; MUST check the CPUID feature flags to see that these instructions are available
;; and fail to init if they are not.
;; fxstor [rdi]
FXSTOR_RDI MACRO
db 0fh, 0aeh, 00000111y ; mod = 00, reg/op = 000, r/m = 111 = [rdi]
ENDM
;; fxrstor [rsi]
FXRSTOR_RSI MACRO
db 0fh, 0aeh, 00001110y ; mod = 00, reg/op = 001, r/m = 110 = [rsi]
ENDM
data SEGMENT
public OrigVector, InterruptEntryStub, StubSize, CommonIdtEntry, FxStorSupport
StubSize dd InterruptEntryStubEnd - InterruptEntryStub
AppRsp dq 1111111111111111h ; ?
DebugRsp dq 2222222222222222h ; ?
ExtraPush dq 3333333333333333h ; ?
ExceptData dq 4444444444444444h ; ?
Rflags dq 5555555555555555h ; ?
OrigVector dq 6666666666666666h ; ?
;; The declarations below define the memory region that will be used for the debug stack.
;; The context record will be built by pushing register values onto this stack.
;; It is imparitive that alignment be carefully managed, since the FXSTOR and
;; FXRSTOR instructions will GP fault if their memory operand is not 16 byte aligned.
;;
;; The stub will switch stacks from the application stack to the debuger stack
;; and pushes the exception number.
;;
;; Then we building the context record on the stack. Since the stack grows down,
;; we push the fields of the context record from the back to the front. There
;; are 336 bytes of stack used prior allocating the 512 bytes of stack to be
;; used as the memory buffer for the fxstor instruction. Therefore address of
;; the buffer used for the FXSTOR instruction is &Eax - 336 - 512, which
;; must be 16 byte aligned.
;;
;; We carefully locate the stack to make this happen.
;;
;; For reference, the context structure looks like this:
;; struct {
;; UINT64 ExceptionData;
;; FX_SAVE_STATE_X64 FxSaveState; // 512 bytes, must be 16 byte aligned
;; UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
;; UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;
;; UINT64 RFlags;
;; UINT64 Ldtr, Tr;
;; UINT64 Gdtr[2], Idtr[2];
;; UINT64 Rip;
;; UINT64 Gs, Fs, Es, Ds, Cs, Ss;
;; UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
;; UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
;; } SYSTEM_CONTEXT_X64; // 64 bit system context record
align 16
DebugStackEnd db "DbgStkEnd >>>>>>" ;; 16 byte long string - must be 16 bytes to preserve alignment
dd 1ffch dup (000000000h) ;; 32K should be enough stack
;; This allocation is coocked to insure
;; that the the buffer for the FXSTORE instruction
;; will be 16 byte aligned also.
;;
ExceptionNumber dq ? ;; first entry will be the vector number pushed by the stub
DebugStackBegin db "<<<< DbgStkBegin" ;; initial debug ESP == DebugStackBegin, set in stub
data ENDS
text SEGMENT
externdef InterruptDistrubutionHub:near
;------------------------------------------------------------------------------
; BOOLEAN
; FxStorSupport (
; void
; )
;
; Abstract: Returns TRUE if FxStor instructions are supported
;
FxStorSupport PROC PUBLIC
;
; cpuid corrupts rbx which must be preserved per the C calling convention
;
push rbx
mov rax, 1
cpuid
mov eax, edx
and rax, FXSTOR_FLAG
shr rax, 24
pop rbx
ret
FxStorSupport ENDP
;------------------------------------------------------------------------------
; void
; Vect2Desc (
; IA32_IDT_GATE_DESCRIPTOR * DestDesc, // rcx
; void (*Vector) (void) // rdx
; )
;
; Abstract: Encodes an IDT descriptor with the given physical address
;
Vect2Desc PROC PUBLIC
mov rax, rdx
mov word ptr [rcx], ax ; write bits 15..0 of offset
mov dx, cs
mov word ptr [rcx+2], dx ; SYS_CODE_SEL from GDT
mov word ptr [rcx+4], 0e00h OR 8000h ; type = 386 interrupt gate, present
shr rax, 16
mov word ptr [rcx+6], ax ; write bits 31..16 of offset
shr rax, 16
mov dword ptr [rcx+8], eax ; write bits 63..32 of offset
ret
Vect2Desc ENDP
;------------------------------------------------------------------------------
; InterruptEntryStub
;
; Abstract: This code is not a function, but is a small piece of code that is
; copied and fixed up once for each IDT entry that is hooked.
;
InterruptEntryStub::
push 0 ; push vector number - will be modified before installed
db 0e9h ; jump rel32
dd 0 ; fixed up to relative address of CommonIdtEntry
InterruptEntryStubEnd:
;------------------------------------------------------------------------------
; CommonIdtEntry
;
; Abstract: This code is not a function, but is the common part for all IDT
; vectors.
;
CommonIdtEntry::
;;
;; At this point, the stub has saved the current application stack esp into AppRsp
;; and switched stacks to the debug stack, where it pushed the vector number
;;
;; The application stack looks like this:
;;
;; ...
;; (last application stack entry)
;; [16 bytes alignment, do not care it]
;; SS from interrupted task
;; RSP from interrupted task
;; rflags from interrupted task
;; CS from interrupted task
;; RIP from interrupted task
;; Error code <-------------------- Only present for some exeption types
;;
;; Vector Number <----------------- pushed in our IDT Entry
;;
;; The stub switched us to the debug stack and pushed the interrupt number.
;;
;; Next, construct the context record. It will be build on the debug stack by
;; pushing the registers in the correct order so as to create the context structure
;; on the debug stack. The context record must be built from the end back to the
;; beginning because the stack grows down...
;
;; For reference, the context record looks like this:
;;
;; typedef
;; struct {
;; UINT64 ExceptionData;
;; FX_SAVE_STATE_X64 FxSaveState;
;; UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
;; UINT64 Cr0, Cr2, Cr3, Cr4, Cr8;
;; UINT64 RFlags;
;; UINT64 Ldtr, Tr;
;; UINT64 Gdtr[2], Idtr[2];
;; UINT64 Rip;
;; UINT64 Gs, Fs, Es, Ds, Cs, Ss;
;; UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
;; UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
;; } SYSTEM_CONTEXT_X64; // 64 bit system context record
;; NOTE: we save rsp here to prevent compiler put rip reference cause error AppRsp
push rax
mov rax, qword ptr [rsp][8] ; save vector number
mov ExceptionNumber, rax ; save vector number
pop rax
add rsp, 8 ; pop vector number
mov AppRsp, rsp ; save stack top
mov rsp, offset DebugStackBegin ; switch to debugger stack
sub rsp, 8 ; leave space for vector number
;; UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
;; UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
push r15
push r14
push r13
push r12
push r11
push r10
push r9
push r8
push rax
push rcx
push rdx
push rbx
push rsp
push rbp
push rsi
push rdi
;; Save interrupt state rflags register...
pushfq
pop rax
mov qword ptr Rflags, rax
;; We need to determine if any extra data was pushed by the exception, and if so, save it
;; To do this, we check the exception number pushed by the stub, and cache the
;; result in a variable since we'll need this again.
cmp ExceptionNumber, EXCPT64_DOUBLE_FAULT
jz ExtraPushOne
cmp ExceptionNumber, EXCPT64_INVALID_TSS
jz ExtraPushOne
cmp ExceptionNumber, EXCPT64_SEG_NOT_PRESENT
jz ExtraPushOne
cmp ExceptionNumber, EXCPT64_STACK_FAULT
jz ExtraPushOne
cmp ExceptionNumber, EXCPT64_GP_FAULT
jz ExtraPushOne
cmp ExceptionNumber, EXCPT64_PAGE_FAULT
jz ExtraPushOne
cmp ExceptionNumber, EXCPT64_ALIGNMENT_CHECK
jz ExtraPushOne
mov ExtraPush, 0
mov ExceptData, 0
jmp ExtraPushDone
ExtraPushOne:
mov ExtraPush, 1
;; If there's some extra data, save it also, and modify the saved AppRsp to effectively
;; pop this value off the application's stack.
mov rax, AppRsp
mov rbx, [rax]
mov ExceptData, rbx
add rax, 8
mov AppRsp, rax
ExtraPushDone:
;; The "push" above pushed the debug stack rsp. Since what we're actually doing
;; is building the context record on the debug stack, we need to save the pushed
;; debug RSP, and replace it with the application's last stack entry...
mov rax, [rsp + 24]
mov DebugRsp, rax
mov rax, AppRsp
mov rax, QWORD PTR [rax + 24]
; application stack has ss, rsp, rflags, cs, & rip, so
; last actual application stack entry is saved at offset
; 24 bytes from stack top.
mov [rsp + 24], rax
;; continue building context record
;; UINT64 Gs, Fs, Es, Ds, Cs, Ss; insure high 16 bits of each is zero
mov rax, ss
push rax
; CS from application is one entry back in application stack
mov rax, AppRsp
movzx rax, word ptr [rax + 8]
push rax
mov rax, ds
push rax
mov rax, es
push rax
mov rax, fs
push rax
mov rax, gs
push rax
;; UINT64 Rip;
; Rip from application is on top of application stack
mov rax, AppRsp
push qword ptr [rax]
;; UINT64 Gdtr[2], Idtr[2];
push 0
push 0
sidt fword ptr [rsp]
push 0
push 0
sgdt fword ptr [rsp]
;; UINT64 Ldtr, Tr;
xor rax, rax
str ax
push rax
sldt ax
push rax
;; UINT64 RFlags;
;; Rflags from application is two entries back in application stack
mov rax, AppRsp
push qword ptr [rax + 16]
;; UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;
;; insure FXSAVE/FXRSTOR is enabled in CR4...
;; ... while we're at it, make sure DE is also enabled...
mov rax, cr8
push rax
mov rax, cr4
or rax, 208h
mov cr4, rax
push rax
mov rax, cr3
push rax
mov rax, cr2
push rax
push 0
mov rax, cr0
push rax
;; UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
mov rax, dr7
push rax
;; clear Dr7 while executing debugger itself
xor rax, rax
mov dr7, rax
mov rax, dr6
push rax
;; insure all status bits in dr6 are clear...
xor rax, rax
mov dr6, rax
mov rax, dr3
push rax
mov rax, dr2
push rax
mov rax, dr1
push rax
mov rax, dr0
push rax
;; FX_SAVE_STATE_X64 FxSaveState;
sub rsp, 512
mov rdi, rsp
; IMPORTANT!! The debug stack has been carefully constructed to
; insure that rsp and rdi are 16 byte aligned when we get here.
; They MUST be. If they are not, a GP fault will occur.
FXSTOR_RDI
;; UEFI calling convention for x64 requires that Direction flag in EFLAGs is clear
cld
;; UINT64 ExceptionData;
mov rax, ExceptData
push rax
; call to C code which will in turn call registered handler
; pass in the vector number
mov rdx, rsp
mov rcx, ExceptionNumber
sub rsp, 40
call InterruptDistrubutionHub
add rsp, 40
; restore context...
;; UINT64 ExceptionData;
add rsp, 8
;; FX_SAVE_STATE_X64 FxSaveState;
mov rsi, rsp
FXRSTOR_RSI
add rsp, 512
;; UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
pop rax
mov dr0, rax
pop rax
mov dr1, rax
pop rax
mov dr2, rax
pop rax
mov dr3, rax
;; skip restore of dr6. We cleared dr6 during the context save.
add rsp, 8
pop rax
mov dr7, rax
;; UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;
pop rax
mov cr0, rax
add rsp, 8
pop rax
mov cr2, rax
pop rax
mov cr3, rax
pop rax
mov cr4, rax
pop rax
mov cr8, rax
;; UINT64 RFlags;
mov rax, AppRsp
pop qword ptr [rax + 16]
;; UINT64 Ldtr, Tr;
;; UINT64 Gdtr[2], Idtr[2];
;; Best not let anyone mess with these particular registers...
add rsp, 48
;; UINT64 Rip;
pop qword ptr [rax]
;; UINT64 Gs, Fs, Es, Ds, Cs, Ss;
;; NOTE - modified segment registers could hang the debugger... We
;; could attempt to insulate ourselves against this possibility,
;; but that poses risks as well.
;;
pop rax
; mov gs, rax
pop rax
; mov fs, rax
pop rax
mov es, rax
pop rax
mov ds, rax
mov rax, AppRsp
pop qword ptr [rax + 8]
pop rax
mov ss, rax
;; The next stuff to restore is the general purpose registers that were pushed
;; using the "push" instruction.
;;
;; The value of RSP as stored in the context record is the application RSP
;; including the 5 entries on the application stack caused by the exception
;; itself. It may have been modified by the debug agent, so we need to
;; determine if we need to relocate the application stack.
mov rbx, [rsp + 24] ; move the potentially modified AppRsp into rbx
mov rax, AppRsp
mov rax, QWORD PTR [rax + 24]
cmp rbx, rax
je NoAppStackMove
mov rax, AppRsp
mov rcx, [rax] ; RIP
mov [rbx], rcx
mov rcx, [rax + 8] ; CS
mov [rbx + 8], rcx
mov rcx, [rax + 16] ; RFLAGS
mov [rbx + 16], rcx
mov rcx, [rax + 24] ; RSP
mov [rbx + 24], rcx
mov rcx, [rax + 32] ; SS
mov [rbx + 32], rcx
mov rax, rbx ; modify the saved AppRsp to the new AppRsp
mov AppRsp, rax
NoAppStackMove:
mov rax, DebugRsp ; restore the DebugRsp on the debug stack
; so our "pop" will not cause a stack switch
mov [rsp + 24], rax
cmp ExceptionNumber, 068h
jne NoChain
Chain:
;; Restore rflags so when we chain, the flags will be exactly as if we were never here.
;; We gin up the stack to do an iretq so we can get ALL the flags.
mov rax, AppRsp
mov rbx, [rax + 40]
push rbx
mov rax, ss
push rax
mov rax, rsp
add rax, 16
push rax
mov rax, AppRsp
mov rbx, [rax + 16]
and rbx, NOT 300h ; special handling for IF and TF
push rbx
mov rax, cs
push rax
mov rax, offset PhonyIretq
push rax
iretq
PhonyIretq:
;; UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
;; UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
pop rdi
pop rsi
pop rbp
pop rsp
pop rbx
pop rdx
pop rcx
pop rax
pop r8
pop r9
pop r10
pop r11
pop r12
pop r13
pop r14
pop r15
;; Switch back to application stack
mov rsp, AppRsp
;; Jump to original handler
jmp OrigVector
NoChain:
;; UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
;; UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
pop rdi
pop rsi
pop rbp
pop rsp
pop rbx
pop rdx
pop rcx
pop rax
pop r8
pop r9
pop r10
pop r11
pop r12
pop r13
pop r14
pop r15
;; Switch back to application stack
mov rsp, AppRsp
;; We're outa here...
iretq
text ENDS
END