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|
; $Id: bootsector2-cpu-db-loop.asm $
;; @file
; Bootsector test for debug exception loop.
;
; Recommended (but not necessary):
; VBoxManage setextradata bs-cpu-db-loop VBoxInternal/Devices/VMMDev/0/Config/TestingEnabled 1
;
;
; Copyright (C) 2007-2023 Oracle and/or its affiliates.
;
; This file is part of VirtualBox base platform packages, as
; available from https://www.virtualbox.org.
;
; This program is free software; you can redistribute it and/or
; modify it under the terms of the GNU General Public License
; as published by the Free Software Foundation, in version 3 of the
; License.
;
; This program is distributed in the hope that it will be useful, but
; WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
; General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this program; if not, see <https://www.gnu.org/licenses>.
;
; The contents of this file may alternatively be used under the terms
; of the Common Development and Distribution License Version 1.0
; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
; in the VirtualBox distribution, in which case the provisions of the
; CDDL are applicable instead of those of the GPL.
;
; You may elect to license modified versions of this file under the
; terms and conditions of either the GPL or the CDDL or both.
;
; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
;
;*******************************************************************************
;* Header Files *
;*******************************************************************************
%include "iprt/asmdefs.mac"
%include "iprt/x86.mac"
%include "VBox/VMMDevTesting.mac"
;
; Include and execute the init code.
;
%define BS2_INIT_PE32
%define BS2_WITH_TRAPS
%define BS2_WITH_XCPT_DB_CLEARING_TF
%define BS2_INC_PE16
%define BS2_INC_PE32
%define BS2_INC_RM ; for SetCpuModeGlobals_rm
%include "bootsector2-common-init-code.mac"
;
; The main() function.
;
BEGINPROC main
BITS 32
;
; Test prologue.
;
mov ax, .s_szTstName
call TestInit_p32
call Bs2EnableA20_p32
cli ; raw-mode hack
sub esp, 20h
call Bs2Thunk_p32_p16
BITS 16
;
; We require a stack that can wrap around here. The default stack
; doesn't allow us to do this, so we'll configure a custom one
; where the page tables usually are.
;
mov eax, [bs2Gdt + BS2_SEL_SS16]
mov ebx, [bs2Gdt + BS2_SEL_SS16 + 4]
and eax, 0xffff
or eax, (BS2_PXX_BASE & 0xffff) << 16
and ebx, 0x00ffff00
or ebx, BS2_PXX_BASE & 0xff000000
or ebx, (BS2_PXX_BASE & 0x00ff0000) >> 16
mov [bs2GdtSpare0], eax
mov [bs2GdtSpare0 + 4], ebx
;
; Switch the stack.
;
mov ax, ss
mov es, ax ; saved ss
mov edi, esp ; saved esp
mov ax, BS2_SEL_SPARE0
mov ss, ax
mov esp, 0xfff0
;
; Arm the breakpoint.
;
and dword [esp + 2], 0
sidt [esp]
mov eax, [esp + 2]
add eax, 8
mov dr0, eax
mov eax, X86_DR7_RA1_MASK | X86_DR7_GE \
| X86_DR7_L0 | X86_DR7_G0 | X86_DR7_RW(0, X86_DR7_RW_RW) | X86_DR7_LEN(0, X86_DR7_LEN_DWORD)
mov dr7, eax
;
; Trigger a single step exception.
;
pushf
or word [xSP], X86_EFL_TF
popf
xchg eax, ebx
xchg edx, ecx ; should get a #DB here.
xchg eax, ebx
xchg edx, ecx
;
; If we get thus far, we've failed.
;
mov ax, es ; restore ss
mov ss, ax
mov esp, edi ; restore esp
call Bs2Thunk_p16_p32
BITS 32
mov eax, .s_szFailed
call TestFailed_p32
;
; We're done.
;
call TestTerm_p32
add esp, 20h
ret
.s_szTstName:
db 'tstCpuDbLoop', 0
.s_szFailed:
db 'no #DB loop detected',0
ENDPROC main
;
; End sections and image.
;
%include "bootsector2-common-end.mac"
|
