diff options
author | Tian, Hot <hot.tian@intel.com> | 2014-01-22 08:38:50 +0000 |
---|---|---|
committer | hhtian <hhtian@6f19259b-4bc3-4df7-8a09-765794883524> | 2014-01-22 08:38:50 +0000 |
commit | 4b738c76f56f8eda171f14b8f9b20e34b66be476 (patch) | |
tree | 353ba43c75023a7d0a88c59389e4bb2ba7c94f0c /MdeModulePkg/Universal/DebugSupportDxe | |
parent | 4c8f6044a2ae275071ab6cd6557b584784c093ce (diff) | |
download | edk2-4b738c76f56f8eda171f14b8f9b20e34b66be476.tar.gz edk2-4b738c76f56f8eda171f14b8f9b20e34b66be476.tar.bz2 edk2-4b738c76f56f8eda171f14b8f9b20e34b66be476.zip |
Fix CRLF format
Signed-off-by: Tian, Hot <hot.tian@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15155 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'MdeModulePkg/Universal/DebugSupportDxe')
-rw-r--r-- | MdeModulePkg/Universal/DebugSupportDxe/X64/AsmFuncs.S | 1102 |
1 files changed, 551 insertions, 551 deletions
diff --git a/MdeModulePkg/Universal/DebugSupportDxe/X64/AsmFuncs.S b/MdeModulePkg/Universal/DebugSupportDxe/X64/AsmFuncs.S index e6a40e8dad..9783ec6b80 100644 --- a/MdeModulePkg/Universal/DebugSupportDxe/X64/AsmFuncs.S +++ b/MdeModulePkg/Universal/DebugSupportDxe/X64/AsmFuncs.S @@ -1,551 +1,551 @@ -///**@file -// Low leve x64 specific debug support functions. -// -// Copyright (c) 2006 - 2011, 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 - movzxw 8(%rax), %rax - pushq %rax - - mov %ds, %rax - pushq %rax - movw %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 +///**@file
+// Low leve x64 specific debug support functions.
+//
+// Copyright (c) 2006 - 2011, 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
+ movzxw 8(%rax), %rax
+ pushq %rax
+
+ mov %ds, %rax
+ pushq %rax
+ movw %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
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