mirror of https://github.com/acidanthera/audk.git
552 lines
21 KiB
ArmAsm
552 lines
21 KiB
ArmAsm
///**@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
|