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| ;------------------------------------------------------------------------------
| ;
| ; Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
| ; SPDX-License-Identifier: BSD-2-Clause-Patent
| ;
| ; Module Name:
| ;
| ; AsmFuncs.nasm
| ;
| ; Abstract:
| ;
| ; Debug interrupt handle functions.
| ;
| ;------------------------------------------------------------------------------
|
| #include "DebugException.h"
|
| SECTION .data
|
| extern ASM_PFX(InterruptProcess)
| global ASM_PFX(Exception0Handle)
| global ASM_PFX(TimerInterruptHandle)
| global ASM_PFX(ExceptionStubHeaderSize)
|
| %macro AGENT_HANDLER_SIGNATURE 0
| db 0x41, 0x47, 0x54, 0x48 ; SIGNATURE_32('A','G','T','H')
| %endmacro
|
| ASM_PFX(ExceptionStubHeaderSize): dd Exception1Handle - ASM_PFX(Exception0Handle) ;
| CommonEntryAddr: dq CommonEntry ;
|
| DEFAULT REL
| SECTION .text
|
| AGENT_HANDLER_SIGNATURE
| ASM_PFX(Exception0Handle):
| cli
| push rcx
| mov rcx, dword 0
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception1Handle:
| cli
| push rcx
| mov rcx, dword 1
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception2Handle:
| cli
| push rcx
| mov rcx, dword 2
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception3Handle:
| cli
| push rcx
| mov rcx, dword 3
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception4Handle:
| cli
| push rcx
| mov rcx, dword 4
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception5Handle:
| cli
| push rcx
| mov rcx, dword 5
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception6Handle:
| cli
| push rcx
| mov rcx, dword 6
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception7Handle:
| cli
| push rcx
| mov rcx, dword 7
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception8Handle:
| cli
| push rcx
| mov rcx, dword 8
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception9Handle:
| cli
| push rcx
| mov rcx, dword 9
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception10Handle:
| cli
| push rcx
| mov rcx, dword 10
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception11Handle:
| cli
| push rcx
| mov rcx, dword 11
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception12Handle:
| cli
| push rcx
| mov rcx, dword 12
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception13Handle:
| cli
| push rcx
| mov rcx, dword 13
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception14Handle:
| cli
| push rcx
| mov rcx, dword 14
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception15Handle:
| cli
| push rcx
| mov rcx, dword 15
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception16Handle:
| cli
| push rcx
| mov rcx, dword 16
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception17Handle:
| cli
| push rcx
| mov rcx, dword 17
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception18Handle:
| cli
| push rcx
| mov rcx, dword 18
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| Exception19Handle:
| cli
| push rcx
| mov rcx, dword 19
| jmp qword [CommonEntryAddr]
| AGENT_HANDLER_SIGNATURE
| ASM_PFX(TimerInterruptHandle):
| cli
| push rcx
| mov rcx, dword 32
| jmp qword [CommonEntryAddr]
|
| CommonEntry:
| ; We need to determine if any extra data was pushed by the exception
| cmp rcx, DEBUG_EXCEPT_DOUBLE_FAULT
| je NoExtrPush
| cmp rcx, DEBUG_EXCEPT_INVALID_TSS
| je NoExtrPush
| cmp rcx, DEBUG_EXCEPT_SEG_NOT_PRESENT
| je NoExtrPush
| cmp rcx, DEBUG_EXCEPT_STACK_FAULT
| je NoExtrPush
| cmp rcx, DEBUG_EXCEPT_GP_FAULT
| je NoExtrPush
| cmp rcx, DEBUG_EXCEPT_PAGE_FAULT
| je NoExtrPush
| cmp rcx, DEBUG_EXCEPT_ALIGNMENT_CHECK
| je NoExtrPush
|
| push qword [rsp]
| mov qword [rsp + 8], 0
|
| NoExtrPush:
| push rbp
| mov rbp, rsp
|
| ; store 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
|
| mov r8, cr8
| push r8
|
| ; store UINT64 Rdi, Rsi, Rbp, Rsp, Rdx, Rcx, Rbx, Rax;
| push rax
| push rbx
| push qword [rbp + 8] ; original rcx
| push rdx
| push qword [rbp + 6 * 8] ; original rsp
| push qword [rbp] ; original rbp
| push rsi
| push rdi
|
| ;; UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;
| ;; insure FXSAVE/FXRSTOR is enabled in CR4...
| ;; ... while we're at it, make sure DE is also enabled...
| mov rax, cr4
| or rax, 0x208
| mov cr4, rax
| push rax
| mov rax, cr3
| push rax
| mov rax, cr2
| push rax
| push 0
| mov rax, cr0
| push rax
|
| xor rax, rax
| mov rax, Ss
| push rax
| mov rax, Cs
| push rax
| mov rax, Ds
| push rax
| mov rax, Es
| push rax
| mov rax, Fs
| push rax
| mov rax, Gs
| push rax
|
| ;; EIP
| mov rax, [rbp + 8 * 3] ; EIP
| push rax
|
| ;; UINT64 Gdtr[2], Idtr[2];
| sub rsp, 16
| sidt [rsp]
| sub rsp, 16
| sgdt [rsp]
|
| ;; UINT64 Ldtr, Tr;
| xor rax, rax
| str ax
| push rax
| sldt ax
| push rax
|
| ;; EFlags
| mov rax, [rbp + 8 * 5]
| 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
|
| ;; Dr6
| 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
|
| ;; Clear Direction Flag
| cld
|
| sub rsp, 512
| mov rdi, rsp
| ;; Clear the buffer
| xor rax, rax
| push rcx
| mov rcx, dword 64 ;= 512 / 8
| rep stosq
| pop rcx
| mov rdi, rsp
| db 0xf, 0xae, 00000111y ;fxsave [rdi]
|
| ;; save the exception data
| push qword [rbp + 16]
|
| ; call the C interrupt process function
| mov rdx, rsp ; Structure
| mov r15, rcx ; save vector in r15
|
| ;
| ; Per X64 calling convention, allocate maximum parameter stack space
| ; and make sure RSP is 16-byte aligned
| ;
| sub rsp, 32 + 8
| call ASM_PFX(InterruptProcess)
| add rsp, 32 + 8
|
| ;; skip the exception data
| add rsp, 8
|
| mov rsi, rsp
| db 0xf, 0xae, 00001110y ; 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
|
| ;; set EFlags
| pop qword [rbp + 8 * 5]
|
| ;; UINT64 Ldtr, Tr;
| ;; UINT64 Gdtr[2], Idtr[2];
| ;; Best not let anyone mess with these particular registers...
| add rsp, 24 * 2
|
| ;; UINT64 Eip;
| pop qword [rbp + 8 * 3] ; set EIP in stack
|
| ;; 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
| pop rax
| pop rax
| mov es, rax
| pop rax
| mov ds, rax
| pop qword [rbp + 8 * 4] ; Set CS in stack
| pop rax
| mov ss, rax
|
| ;; UINT64 Cr0, Cr1, Cr2, Cr3, Cr4;
| pop rax
| mov cr0, rax
| add rsp, 8 ; skip for Cr1
| pop rax
| mov cr2, rax
| pop rax
| mov cr3, rax
| pop rax
| mov cr4, rax
|
| ;; restore general register
| pop rdi
| pop rsi
| add rsp, 8 ; skip rbp
| add rsp, 8 ; skip rsp
| pop rdx
| pop rcx
| pop rbx
| pop rax
|
| pop r8
| mov cr8, r8
|
| ; store UINT64 r8, r9, r10, r11, r12, r13, r14, r15;
| pop r8
| pop r9
| pop r10
| pop r11
| pop r12
| pop r13
| pop r14
| pop r15
|
| mov rsp, rbp
| pop rbp
| add rsp, 16 ; skip rcx and error code
|
| iretq
|
|
|