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; $Id: LegacyandAMD64.mac $
;; @file
; VMM - World Switchers, 32-bit to AMD64 intermediate context.
;
; This is used for running 64-bit guest on 32-bit hosts, not
; normal raw-mode.  All the code involved is contained in this
; file.
;

;
; Copyright (C) 2006-2013 Oracle Corporation
;
; This file is part of VirtualBox Open Source Edition (OSE), as
; available from http://www.virtualbox.org. This file is free software;
; you can redistribute it and/or modify it under the terms of the GNU
; General Public License (GPL) as published by the Free Software
; Foundation, in version 2 as it comes in the "COPYING" file of the
; VirtualBox OSE distribution. VirtualBox OSE is distributed in the
; hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
;


;*******************************************************************************
;*  Defined Constants And Macros                                               *
;*******************************************************************************
;; @note These values are from the HM64ON32OP enum in hm.h.
%define HM64ON32OP_VMXRCStartVM64       1
%define HM64ON32OP_SVMRCVMRun64         2
%define HM64ON32OP_HMRCSaveGuestFPU64   3
%define HM64ON32OP_HMRCSaveGuestDebug64 4
%define HM64ON32OP_HMRCTestSwitcher64   5

;;
; This macro is used for storing a debug code in a CMOS location.
;
; If we tripple fault or something, the debug code can be retrieved and we
; might have a clue as to where the problem occurred.  The code is currently
; using CMOS register 3 in the 2nd bank as this _seems_ to be unused on my
; Extreme4 X79 asrock mainboard.
;
; @param %1     The debug code (byte)
; @note Trashes AL.
;
%macro DEBUG_CMOS_TRASH_AL 1
%ifdef VBOX_WITH_64ON32_CMOS_DEBUG
    mov     al, 3
    out     72h, al
    mov     al, %1
    out     73h, al
    in      al, 73h
%endif
%endmacro

;;
; Version of DEBUG_CMOS_TRASH_AL that saves AL on the stack and therefore
; doesn't trash any registers.
;
%macro DEBUG_CMOS_STACK64 1
%ifdef VBOX_WITH_64ON32_CMOS_DEBUG
    push    rax
    DEBUG_CMOS_TRASH_AL %1
    pop     rax
%endif
%endmacro

;;
; Version of DEBUG_CMOS_TRASH_AL that saves AL on the stack and therefore
; doesn't trash any registers.
;
%macro DEBUG_CMOS_STACK32 1
%ifdef VBOX_WITH_64ON32_CMOS_DEBUG
    push    eax
    DEBUG_CMOS_TRASH_AL %1
    pop     eax
%endif
%endmacro


;; Stubs for making OS/2 compile (though, not work).
%ifdef RT_OS_OS2 ;; @todo fix OMF support in yasm and kick nasm out completely.
 %macro vmwrite 2,
    int3
 %endmacro
 %define vmlaunch int3
 %define vmresume int3
 %define vmsave int3
 %define vmload int3
 %define vmrun int3
 %define clgi int3
 %define stgi int3
 %macro invlpga 2,
    int3
 %endmacro
%endif

;; Debug options
;%define DEBUG_STUFF 1
;%define STRICT_IF 1


;*******************************************************************************
;* Header Files                                                                *
;*******************************************************************************
%include "VBox/asmdefs.mac"
%include "iprt/x86.mac"
%include "VBox/err.mac"
%include "VBox/apic.mac"

%include "VBox/vmm/cpum.mac"
%include "VBox/vmm/stam.mac"
%include "VBox/vmm/vm.mac"
%include "VBox/vmm/hm_vmx.mac"
%include "CPUMInternal.mac"
%include "HMInternal.mac"
%include "VMMSwitcher.mac"


;
; Start the fixup records
;   We collect the fixups in the .data section as we go along
;   It is therefore VITAL that no-one is using the .data section
;   for anything else between 'Start' and 'End'.
;
BEGINDATA
GLOBALNAME Fixups



BEGINCODE
GLOBALNAME Start

BITS 32

;;
; The C interface.
; @param    [esp + 04h]  Param 1 - VM handle
; @param    [esp + 08h]  Param 2 - Offset from VM::CPUM to the CPUMCPU
;                                  structure for the calling EMT.
;
BEGINPROC vmmR0ToRawMode
%ifdef DEBUG_STUFF
    COM32_S_NEWLINE
    COM32_S_CHAR '^'
%endif

%ifdef VBOX_WITH_STATISTICS
    ;
    ; Switcher stats.
    ;
    FIXUP FIX_HC_VM_OFF, 1, VM.StatSwitcherToGC
    mov     edx, 0ffffffffh
    STAM_PROFILE_ADV_START edx
%endif

    push    ebp
    mov     ebp, [esp + 12]             ; CPUMCPU offset

    ; turn off interrupts
    pushf
    cli
    ;DEBUG_CMOS_STACK32 10h

    ;
    ; Call worker.
    ;
    FIXUP FIX_HC_CPUM_OFF, 1, 0
    mov     edx, 0ffffffffh
    push    cs                          ; allow for far return and restore cs correctly.
    call    NAME(vmmR0ToRawModeAsm)

%ifdef VBOX_WITH_VMMR0_DISABLE_LAPIC_NMI
    ; Restore blocked Local APIC NMI vectors
    ; Do this here to ensure the host CS is already restored
    mov     ecx, [edx + CPUMCPU.fApicDisVectors]
    test    ecx, ecx
    jz      gth_apic_done
    cmp     byte [edx + CPUMCPU.fX2Apic], 1
    je      gth_x2apic

    mov     edx, [edx + CPUMCPU.pvApicBase]
    shr     ecx, 1
    jnc     gth_nolint0
    and     dword [edx + APIC_REG_LVT_LINT0], ~APIC_REG_LVT_MASKED
gth_nolint0:
    shr     ecx, 1
    jnc     gth_nolint1
    and     dword [edx + APIC_REG_LVT_LINT1], ~APIC_REG_LVT_MASKED
gth_nolint1:
    shr     ecx, 1
    jnc     gth_nopc
    and     dword [edx + APIC_REG_LVT_PC], ~APIC_REG_LVT_MASKED
gth_nopc:
    shr     ecx, 1
    jnc     gth_notherm
    and     dword [edx + APIC_REG_LVT_THMR], ~APIC_REG_LVT_MASKED
gth_notherm:
    jmp     gth_apic_done

gth_x2apic:
    ;DEBUG_CMOS_STACK32 7ch
    push    eax                         ; save eax
    push    ebx                         ; save it for fApicDisVectors
    push    edx                         ; save edx just in case.
    mov     ebx, ecx                    ; ebx = fApicDisVectors, ecx free for MSR use
    shr     ebx, 1
    jnc     gth_x2_nolint0
    mov     ecx, MSR_IA32_X2APIC_START + (APIC_REG_LVT_LINT0 >> 4)
    rdmsr
    and     eax, ~APIC_REG_LVT_MASKED
    wrmsr
gth_x2_nolint0:
    shr     ebx, 1
    jnc     gth_x2_nolint1
    mov     ecx, MSR_IA32_X2APIC_START + (APIC_REG_LVT_LINT1 >> 4)
    rdmsr
    and     eax, ~APIC_REG_LVT_MASKED
    wrmsr
gth_x2_nolint1:
    shr     ebx, 1
    jnc     gth_x2_nopc
    mov     ecx, MSR_IA32_X2APIC_START + (APIC_REG_LVT_PC >> 4)
    rdmsr
    and     eax, ~APIC_REG_LVT_MASKED
    wrmsr
gth_x2_nopc:
    shr     ebx, 1
    jnc     gth_x2_notherm
    mov     ecx, MSR_IA32_X2APIC_START + (APIC_REG_LVT_THMR >> 4)
    rdmsr
    and     eax, ~APIC_REG_LVT_MASKED
    wrmsr
gth_x2_notherm:
    pop     edx
    pop     ebx
    pop     eax

gth_apic_done:
%endif

    ; restore original flags
    ;DEBUG_CMOS_STACK32 7eh
    popf
    pop     ebp

%ifdef VBOX_WITH_STATISTICS
    ;
    ; Switcher stats.
    ;
    FIXUP FIX_HC_VM_OFF, 1, VM.StatSwitcherToHC
    mov     edx, 0ffffffffh
    STAM_PROFILE_ADV_STOP edx
%endif

    ;DEBUG_CMOS_STACK32 7fh
    ret

ENDPROC vmmR0ToRawMode

; *****************************************************************************
; vmmR0ToRawModeAsm
;
; Phase one of the switch from host to guest context (host MMU context)
;
; INPUT:
;       - edx       virtual address of CPUM structure (valid in host context)
;       - ebp       offset of the CPUMCPU structure relative to CPUM.
;
; USES/DESTROYS:
;       - eax, ecx, edx, esi
;
; ASSUMPTION:
;       - current CS and DS selectors are wide open
;
; *****************************************************************************
ALIGNCODE(16)
BEGINPROC vmmR0ToRawModeAsm
    ;;
    ;; Save CPU host context
    ;;      Skip eax, edx and ecx as these are not preserved over calls.
    ;;
    CPUMCPU_FROM_CPUM_WITH_OFFSET edx, ebp
%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    ; phys address of scratch page
    mov     eax, dword [edx + CPUMCPU.Guest.dr + 4*8]
    mov     cr2, eax

    mov dword [edx + CPUMCPU.Guest.dr + 4*8], 1
%endif

    ; general registers.
    mov     [edx + CPUMCPU.Host.ebx], ebx
    mov     [edx + CPUMCPU.Host.edi], edi
    mov     [edx + CPUMCPU.Host.esi], esi
    mov     [edx + CPUMCPU.Host.esp], esp
    mov     [edx + CPUMCPU.Host.ebp], ebp ; offCpumCpu!
    ; selectors.
    mov     [edx + CPUMCPU.Host.ds], ds
    mov     [edx + CPUMCPU.Host.es], es
    mov     [edx + CPUMCPU.Host.fs], fs
    mov     [edx + CPUMCPU.Host.gs], gs
    mov     [edx + CPUMCPU.Host.ss], ss
    ; special registers.
    DEBUG32_S_CHAR('s')
    DEBUG32_S_CHAR(';')
    sldt    [edx + CPUMCPU.Host.ldtr]
    sidt    [edx + CPUMCPU.Host.idtr]
    sgdt    [edx + CPUMCPU.Host.gdtr]
    str     [edx + CPUMCPU.Host.tr]

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov dword [edx + CPUMCPU.Guest.dr + 4*8], 2
%endif

%ifdef VBOX_WITH_VMMR0_DISABLE_LAPIC_NMI
    DEBUG32_S_CHAR('f')
    DEBUG32_S_CHAR(';')
    cmp     byte [edx + CPUMCPU.pvApicBase], 1
    je      htg_x2apic

    mov     ebx, [edx + CPUMCPU.pvApicBase]
    or      ebx, ebx
    jz      htg_apic_done
    mov     eax, [ebx + APIC_REG_LVT_LINT0]
    mov     ecx, eax
    and     ecx, (APIC_REG_LVT_MASKED | APIC_REG_LVT_MODE_MASK)
    cmp     ecx, APIC_REG_LVT_MODE_NMI
    jne     htg_nolint0
    or      edi, 0x01
    or      eax, APIC_REG_LVT_MASKED
    mov     [ebx + APIC_REG_LVT_LINT0], eax
    mov     eax, [ebx + APIC_REG_LVT_LINT0] ; write completion
htg_nolint0:
    mov     eax, [ebx + APIC_REG_LVT_LINT1]
    mov     ecx, eax
    and     ecx, (APIC_REG_LVT_MASKED | APIC_REG_LVT_MODE_MASK)
    cmp     ecx, APIC_REG_LVT_MODE_NMI
    jne     htg_nolint1
    or      edi, 0x02
    or      eax, APIC_REG_LVT_MASKED
    mov     [ebx + APIC_REG_LVT_LINT1], eax
    mov     eax, [ebx + APIC_REG_LVT_LINT1] ; write completion
htg_nolint1:
    mov     eax, [ebx + APIC_REG_LVT_PC]
    mov     ecx, eax
    and     ecx, (APIC_REG_LVT_MASKED | APIC_REG_LVT_MODE_MASK)
    cmp     ecx, APIC_REG_LVT_MODE_NMI
    jne     htg_nopc
    or      edi, 0x04
    or      eax, APIC_REG_LVT_MASKED
    mov     [ebx + APIC_REG_LVT_PC], eax
    mov     eax, [ebx + APIC_REG_LVT_PC] ; write completion
htg_nopc:
    mov     eax, [ebx + APIC_REG_VERSION]
    shr     eax, 16
    cmp     al, 5
    jb      htg_notherm
    mov     eax, [ebx + APIC_REG_LVT_THMR]
    mov     ecx, eax
    and     ecx, (APIC_REG_LVT_MASKED | APIC_REG_LVT_MODE_MASK)
    cmp     ecx, APIC_REG_LVT_MODE_NMI
    jne     htg_notherm
    or      edi, 0x08
    or      eax, APIC_REG_LVT_MASKED
    mov     [ebx + APIC_REG_LVT_THMR], eax
    mov     eax, [ebx + APIC_REG_LVT_THMR] ; write completion
htg_notherm:
    mov     [edx + CPUMCPU.fApicDisVectors], edi
    jmp     htg_apic_done

htg_x2apic:
    mov     esi, edx                    ; Save edx.
    xor     edi, edi                    ; fApicDisVectors

    mov     ecx, MSR_IA32_X2APIC_START + (APIC_REG_LVT_LINT0 >> 4)
    rdmsr
    mov     ebx, eax
    and     ebx, (APIC_REG_LVT_MASKED | APIC_REG_LVT_MODE_MASK)
    cmp     ebx, APIC_REG_LVT_MODE_NMI
    jne     htg_x2_nolint0
    or      edi, 0x01
    or      eax, APIC_REG_LVT_MASKED
    wrmsr
htg_x2_nolint0:
    mov     ecx, MSR_IA32_X2APIC_START + (APIC_REG_LVT_LINT1 >> 4)
    rdmsr
    mov     ebx, eax
    and     ebx, (APIC_REG_LVT_MASKED | APIC_REG_LVT_MODE_MASK)
    cmp     ebx, APIC_REG_LVT_MODE_NMI
    jne     htg_x2_nolint1
    or      edi, 0x02
    or      eax, APIC_REG_LVT_MASKED
    wrmsr
htg_x2_nolint1:
    mov     ecx, MSR_IA32_X2APIC_START + (APIC_REG_LVT_PC >> 4)
    rdmsr
    mov     ebx, eax
    and     ebx, (APIC_REG_LVT_MASKED | APIC_REG_LVT_MODE_MASK)
    cmp     ebx, APIC_REG_LVT_MODE_NMI
    jne     htg_x2_nopc
    or      edi, 0x04
    or      eax, APIC_REG_LVT_MASKED
    wrmsr
htg_x2_nopc:
    mov     ecx, MSR_IA32_X2APIC_START + (APIC_REG_VERSION >> 4)
    rdmsr
    shr     eax, 16
    cmp     al, 5
    jb      htg_x2_notherm
    mov     ecx, MSR_IA32_X2APIC_START + (APIC_REG_LVT_THMR >> 4)
    rdmsr
    mov     ebx, eax
    and     ebx, (APIC_REG_LVT_MASKED | APIC_REG_LVT_MODE_MASK)
    cmp     ebx, APIC_REG_LVT_MODE_NMI
    jne     htg_x2_notherm
    or      edi, 0x08
    or      eax, APIC_REG_LVT_MASKED
    wrmsr
htg_x2_notherm:
    mov     edx, esi                    ; Restore edx.
    mov     [edx + CPUMCPU.fApicDisVectors], edi

htg_apic_done:
%endif

    ; control registers.
    mov     eax, cr0
    mov     [edx + CPUMCPU.Host.cr0], eax
    ;Skip cr2; assume host os don't stuff things in cr2. (safe)
    mov     eax, cr3
    mov     [edx + CPUMCPU.Host.cr3], eax
    mov     esi, cr4                      ; esi = cr4, we'll modify it further down.
    mov     [edx + CPUMCPU.Host.cr4], esi

    DEBUG32_S_CHAR('c')
    DEBUG32_S_CHAR(';')

    ; save the host EFER msr
    mov     ebx, edx
    mov     ecx, MSR_K6_EFER
    rdmsr
    mov     [ebx + CPUMCPU.Host.efer], eax
    mov     [ebx + CPUMCPU.Host.efer + 4], edx
    mov     edx, ebx
    DEBUG32_S_CHAR('e')
    DEBUG32_S_CHAR(';')

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov dword [edx + CPUMCPU.Guest.dr + 4*8], 3
%endif

    ; Load new gdt so we can do a far jump after going into 64 bits mode
    ;DEBUG_CMOS_STACK32 16h
    lgdt    [edx + CPUMCPU.Hyper.gdtr]

    DEBUG32_S_CHAR('g')
    DEBUG32_S_CHAR('!')
%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov dword [edx + CPUMCPU.Guest.dr + 4*8], 4
%endif

    ;;
    ;; Clean up CR4.  X86_CR4_PGE, X86_CR4_PCE, X86_CR4_PCIDE (not really
    ;; relevant for 32-bit, but whatever) and X86_CR4_VMXE must be cleared.
    ;;
    and     esi, X86_CR4_VME | X86_CR4_PVI | X86_CR4_TSD | X86_CR4_DE | X86_CR4_PSE | X86_CR4_PAE \
               | X86_CR4_MCE | X86_CR4_OSFSXR | X86_CR4_OSXMMEEXCPT | X86_CR4_SMXE | X86_CR4_OSXSAVE
    mov     cr4, esi

    ;;
    ;; Load Intermediate memory context.
    ;;
    FIXUP SWITCHER_FIX_INTER_CR3_HC, 1
    mov     eax, 0ffffffffh
    mov     cr3, eax
    DEBUG32_CHAR('?')
%ifdef VBOX_WITH_64ON32_CMOS_DEBUG
    DEBUG_CMOS_TRASH_AL 17h
%endif

    ;;
    ;; Jump to identity mapped location
    ;;
    FIXUP FIX_HC_2_ID_NEAR_REL, 1, NAME(IDEnterTarget) - NAME(Start)
    jmp near NAME(IDEnterTarget)


    ; We're now on identity mapped pages!
ALIGNCODE(16)
GLOBALNAME IDEnterTarget
    DEBUG32_CHAR('1')
    DEBUG_CMOS_TRASH_AL 19h

    ; 1. Disable paging.
    mov     ebx, cr0
    and     ebx, ~X86_CR0_PG
    mov     cr0, ebx
    DEBUG32_CHAR('2')
    DEBUG_CMOS_TRASH_AL 1ah

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     eax, cr2
    mov     dword [eax], 3
%endif

    ; 2. Enable PAE.
    mov     ecx, cr4
    or      ecx, X86_CR4_PAE
    mov     cr4, ecx
    DEBUG_CMOS_TRASH_AL 1bh

    ; 3. Load long mode intermediate CR3.
    FIXUP FIX_INTER_AMD64_CR3, 1
    mov     ecx, 0ffffffffh
    mov     cr3, ecx
    DEBUG32_CHAR('3')
    DEBUG_CMOS_TRASH_AL 1ch

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     eax, cr2
    mov     dword [eax], 4
%endif

    ; 4. Enable long mode.
    mov     esi, edx
    mov     ecx, MSR_K6_EFER
    rdmsr
    FIXUP FIX_EFER_OR_MASK, 1
    or      eax, 0ffffffffh
    and     eax, ~(MSR_K6_EFER_FFXSR) ; turn off fast fxsave/fxrstor (skipping xmm regs)
    wrmsr
    mov     edx, esi
    DEBUG32_CHAR('4')
    DEBUG_CMOS_TRASH_AL 1dh

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     eax, cr2
    mov     dword [eax], 5
%endif

    ; 5. Enable paging.
    or      ebx, X86_CR0_PG
    ; Disable ring 0 write protection too
    and     ebx, ~X86_CR0_WRITE_PROTECT
    mov     cr0, ebx
    DEBUG32_CHAR('5')

    ; Jump from compatibility mode to 64-bit mode.
    FIXUP FIX_ID_FAR32_TO_64BIT_MODE, 1, NAME(IDEnter64Mode) - NAME(Start)
    jmp     0ffffh:0fffffffeh

    ;
    ; We're in 64-bit mode (ds, ss, es, fs, gs are all bogus).
BITS 64
ALIGNCODE(16)
NAME(IDEnter64Mode):
    DEBUG64_CHAR('6')
    DEBUG_CMOS_TRASH_AL 1eh
    jmp     [NAME(pICEnterTarget) wrt rip]

; 64-bit jump target
NAME(pICEnterTarget):
FIXUP FIX_HC_64BIT_NOCHECK, 0, NAME(ICEnterTarget) - NAME(Start)
dq 0ffffffffffffffffh

; 64-bit pCpum address.
NAME(pCpumIC):
FIXUP FIX_GC_64_BIT_CPUM_OFF, 0, 0
dq 0ffffffffffffffffh

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
NAME(pMarker):
db 'Switch_marker'
%endif

    ;
    ; When we arrive here we're in 64 bits mode in the intermediate context
    ;
ALIGNCODE(16)
GLOBALNAME ICEnterTarget
    ;DEBUG_CMOS_TRASH_AL 1fh
    ; Load CPUM pointer into rdx
    mov     rdx, [NAME(pCpumIC) wrt rip]
    CPUMCPU_FROM_CPUM_WITH_OFFSET edx, ebp

    mov     rax, cs
    mov     ds, rax
    mov     es, rax

    ; Invalidate fs & gs
    mov     rax, 0
    mov     fs, rax
    mov     gs, rax

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov dword [rdx + CPUMCPU.Guest.dr + 4*8], 5
%endif

    ; Setup stack.
    DEBUG64_CHAR('7')
    mov     rsp, 0
    mov     eax, [rdx + CPUMCPU.Hyper.ss.Sel]
    mov     ss, ax
    mov     esp, [rdx + CPUMCPU.Hyper.esp]

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov dword [rdx + CPUMCPU.Guest.dr + 4*8], 6
%endif

%ifdef VBOX_WITH_64ON32_IDT
    ; Set up emergency trap handlers.
    lidt    [rdx + CPUMCPU.Hyper.idtr]
%endif

    ; load the hypervisor function address
    mov     r9, [rdx + CPUMCPU.Hyper.eip]
    DEBUG64_S_CHAR('8')

    ; Check if we need to restore the guest FPU state
    mov     esi, [rdx + CPUMCPU.fUseFlags] ; esi == use flags.
    test    esi, CPUM_SYNC_FPU_STATE
    jz      near htg_fpu_no

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov dword [rdx + CPUMCPU.Guest.dr + 4*8], 7
%endif

    mov     rax, cr0
    mov     rcx, rax                    ; save old CR0
    and     rax, ~(X86_CR0_TS | X86_CR0_EM)
    mov     cr0, rax
    ; Use explicit REX prefix. See @bugref{6398}.
    o64 fxrstor [rdx + CPUMCPU.Guest.fpu]
    mov     cr0, rcx                    ; and restore old CR0 again

    and     dword [rdx + CPUMCPU.fUseFlags], ~CPUM_SYNC_FPU_STATE

htg_fpu_no:
    ; Check if we need to restore the guest debug state
    test    esi, CPUM_SYNC_DEBUG_REGS_GUEST | CPUM_SYNC_DEBUG_REGS_HYPER
    jz      htg_debug_done

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov dword [rdx + CPUMCPU.Guest.dr + 4*8], 8
%endif
    test    esi, CPUM_SYNC_DEBUG_REGS_HYPER
    jnz     htg_debug_hyper

    ; Guest values in DRx, letting the guest access them directly.
    mov     rax, qword [rdx + CPUMCPU.Guest.dr + 0*8]
    mov     dr0, rax
    mov     rax, qword [rdx + CPUMCPU.Guest.dr + 1*8]
    mov     dr1, rax
    mov     rax, qword [rdx + CPUMCPU.Guest.dr + 2*8]
    mov     dr2, rax
    mov     rax, qword [rdx + CPUMCPU.Guest.dr + 3*8]
    mov     dr3, rax
    mov     rax, qword [rdx + CPUMCPU.Guest.dr + 6*8]
    mov     dr6, rax    ; not required for AMD-V

    and     dword [rdx + CPUMCPU.fUseFlags], ~CPUM_SYNC_DEBUG_REGS_GUEST
    or      dword [rdx + CPUMCPU.fUseFlags], CPUM_USED_DEBUG_REGS_GUEST
    jmp     htg_debug_done

htg_debug_hyper:
    ; Combined values in DRx, intercepting all accesses.
    mov     rax, qword [rdx + CPUMCPU.Hyper.dr + 0*8]
    mov     dr0, rax
    mov     rax, qword [rdx + CPUMCPU.Hyper.dr + 1*8]
    mov     dr1, rax
    mov     rax, qword [rdx + CPUMCPU.Hyper.dr + 2*8]
    mov     dr2, rax
    mov     rax, qword [rdx + CPUMCPU.Hyper.dr + 3*8]
    mov     dr3, rax
    mov     rax, qword [rdx + CPUMCPU.Hyper.dr + 6*8]
    mov     dr6, rax    ; not required for AMD-V

    and     dword [rdx + CPUMCPU.fUseFlags], ~CPUM_SYNC_DEBUG_REGS_HYPER
    or      dword [rdx + CPUMCPU.fUseFlags], CPUM_USED_DEBUG_REGS_HYPER

htg_debug_done:

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov dword [rdx + CPUMCPU.Guest.dr + 4*8], 9
%endif

    ;
    ; "Call" the specified helper function.
    ;

    ; parameter for all helper functions (pCtx)
    DEBUG64_CHAR('9')
    lea     rsi, [rdx + CPUMCPU.Guest.fpu]
    lea     rax, [htg_return wrt rip]
    push    rax                         ; return address

    cmp     r9d, HM64ON32OP_VMXRCStartVM64
    jz      NAME(VMXRCStartVM64)
    cmp     r9d, HM64ON32OP_SVMRCVMRun64
    jz      NAME(SVMRCVMRun64)
    cmp     r9d, HM64ON32OP_HMRCSaveGuestFPU64
    jz      NAME(HMRCSaveGuestFPU64)
    cmp     r9d, HM64ON32OP_HMRCSaveGuestDebug64
    jz      NAME(HMRCSaveGuestDebug64)
    cmp     r9d, HM64ON32OP_HMRCTestSwitcher64
    jz      NAME(HMRCTestSwitcher64)
    mov     eax, VERR_HM_INVALID_HM64ON32OP
htg_return:
    DEBUG64_CHAR('r')

    ; Load CPUM pointer into rdx
    mov     rdx, [NAME(pCpumIC) wrt rip]
    CPUMCPU_FROM_CPUM_WITH_OFFSET edx, ebp

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov dword [rdx + CPUMCPU.Guest.dr + 4*8], 10
%endif

    ; Save the return code
    mov     dword [rdx + CPUMCPU.u32RetCode], eax

    ; now let's switch back
    jmp     NAME(vmmRCToHostAsm)   ; rax = returncode.

ENDPROC vmmR0ToRawModeAsm




;
;
; HM code (used to be HMRCA.asm at one point).
; HM code (used to be HMRCA.asm at one point).
; HM code (used to be HMRCA.asm at one point).
;
;



; Load the corresponding guest MSR (trashes rdx & rcx)
%macro LOADGUESTMSR 2
    mov     rcx, %1
    mov     edx, dword [rsi + %2 + 4]
    mov     eax, dword [rsi + %2]
    wrmsr
%endmacro

; Save a guest MSR (trashes rdx & rcx)
; Only really useful for gs kernel base as that one can be changed behind our back (swapgs)
%macro SAVEGUESTMSR 2
    mov     rcx, %1
    rdmsr
    mov     dword [rsi + %2], eax
    mov     dword [rsi + %2 + 4], edx
%endmacro

;; @def MYPUSHSEGS
; Macro saving all segment registers on the stack.
; @param 1  full width register name
%macro MYPUSHSEGS 1
    mov     %1, es
    push    %1
    mov     %1, ds
    push    %1
%endmacro

;; @def MYPOPSEGS
; Macro restoring all segment registers on the stack
; @param 1  full width register name
%macro MYPOPSEGS 1
    pop     %1
    mov     ds, %1
    pop     %1
    mov     es, %1
%endmacro


;/**
; * Prepares for and executes VMLAUNCH/VMRESUME (64 bits guest mode)
; *
; * @returns VBox status code
; * @param   HCPhysCpuPage  VMXON physical address  [rsp+8]
; * @param   HCPhysVmcs     VMCS physical address   [rsp+16]
; * @param   pCache         VMCS cache              [rsp+24]
; * @param   pCtx           Guest context (rsi)
; */
BEGINPROC VMXRCStartVM64
    push    rbp
    mov     rbp, rsp
    DEBUG_CMOS_STACK64 20h

    ; Make sure VT-x instructions are allowed.
    mov     rax, cr4
    or      rax, X86_CR4_VMXE
    mov     cr4, rax

    ; Enter VMX Root Mode.
    vmxon   [rbp + 8 + 8]
    jnc     .vmxon_success
    mov     rax, VERR_VMX_INVALID_VMXON_PTR
    jmp     .vmstart64_vmxon_failed

.vmxon_success:
    jnz     .vmxon_success2
    mov     rax, VERR_VMX_VMXON_FAILED
    jmp     .vmstart64_vmxon_failed

.vmxon_success2:
    ; Activate the VMCS pointer
    vmptrld [rbp + 16 + 8]
    jnc     .vmptrld_success
    mov     rax, VERR_VMX_INVALID_VMCS_PTR
    jmp     .vmstart64_vmxoff_end

.vmptrld_success:
    jnz     .vmptrld_success2
    mov     rax, VERR_VMX_VMPTRLD_FAILED
    jmp     .vmstart64_vmxoff_end

.vmptrld_success2:

    ; Save the VMCS pointer on the stack
    push    qword [rbp + 16 + 8];

    ; Save segment registers.
    MYPUSHSEGS rax

%ifdef VMX_USE_CACHED_VMCS_ACCESSES
    ; Flush the VMCS write cache first (before any other vmreads/vmwrites!).
    mov     rbx, [rbp + 24 + 8]                             ; pCache

 %ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     qword [rbx + VMCSCACHE.uPos], 2
 %endif

 %ifdef DEBUG
    mov     rax, [rbp + 8 + 8]                              ; HCPhysCpuPage
    mov     [rbx + VMCSCACHE.TestIn.HCPhysCpuPage], rax
    mov     rax, [rbp + 16 + 8]                             ; HCPhysVmcs
    mov     [rbx + VMCSCACHE.TestIn.HCPhysVmcs], rax
    mov     [rbx + VMCSCACHE.TestIn.pCache], rbx
    mov     [rbx + VMCSCACHE.TestIn.pCtx], rsi
 %endif

    mov     ecx, [rbx + VMCSCACHE.Write.cValidEntries]
    cmp     ecx, 0
    je      .no_cached_writes
    mov     rdx, rcx
    mov     rcx, 0
    jmp     .cached_write

ALIGN(16)
.cached_write:
    mov     eax, [rbx + VMCSCACHE.Write.aField + rcx*4]
    vmwrite rax, qword [rbx + VMCSCACHE.Write.aFieldVal + rcx*8]
    inc     rcx
    cmp     rcx, rdx
    jl     .cached_write

    mov     dword [rbx + VMCSCACHE.Write.cValidEntries], 0
.no_cached_writes:

 %ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     qword [rbx + VMCSCACHE.uPos], 3
 %endif
    ; Save the pCache pointer.
    push    rbx
%endif

    ; Save the host state that's relevant in the temporary 64-bit mode.
    mov     rdx, cr0
    mov     eax, VMX_VMCS_HOST_CR0
    vmwrite rax, rdx

    mov     rdx, cr3
    mov     eax, VMX_VMCS_HOST_CR3
    vmwrite rax, rdx

    mov     rdx, cr4
    mov     eax, VMX_VMCS_HOST_CR4
    vmwrite rax, rdx

    mov     rdx, cs
    mov     eax, VMX_VMCS_HOST_FIELD_CS
    vmwrite rax, rdx

    mov     rdx, ss
    mov     eax, VMX_VMCS_HOST_FIELD_SS
    vmwrite rax, rdx

%if 0 ; Another experiment regarding tripple faults... Seems not to be necessary.
    sub     rsp, 16
    str     [rsp]
    movsx   rdx, word [rsp]
    mov     eax, VMX_VMCS_HOST_FIELD_TR
    vmwrite rax, rdx
    add     rsp, 16
%endif

    sub     rsp, 16
    sgdt    [rsp + 6]                   ; (The 64-bit base should be aligned, not the word.)
    mov     eax, VMX_VMCS_HOST_GDTR_BASE
    vmwrite rax, [rsp + 6 + 2]
    add     rsp, 16

%ifdef VBOX_WITH_64ON32_IDT
    sub     rsp, 16
    sidt    [rsp + 6]
    mov     eax, VMX_VMCS_HOST_IDTR_BASE
    vmwrite rax, [rsp + 6 + 2] ; [rsi + CPUMCPU.Hyper.idtr + 2] - why doesn't this work?
    add     rsp, 16
    ;call NAME(vmm64On32PrintIdtr)
%endif

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     qword [rbx + VMCSCACHE.uPos], 4
%endif

    ; Hopefully we can ignore TR (we restore it anyway on the way back to 32-bit mode).

    ; First we have to save some final CPU context registers.
    lea     rdx, [.vmlaunch64_done wrt rip]
    mov     rax, VMX_VMCS_HOST_RIP  ; Return address (too difficult to continue after VMLAUNCH?).
    vmwrite rax, rdx
    ; Note: assumes success!

    ; Manual save and restore:
    ;  - General purpose registers except RIP, RSP
    ;
    ; Trashed:
    ;  - CR2 (we don't care)
    ;  - LDTR (reset to 0)
    ;  - DRx (presumably not changed at all)
    ;  - DR7 (reset to 0x400)
    ;  - EFLAGS (reset to RT_BIT(1); not relevant)

%ifndef VBOX_WITH_AUTO_MSR_LOAD_RESTORE
    ; Load the guest LSTAR, CSTAR, SFMASK & KERNEL_GSBASE MSRs.
    LOADGUESTMSR MSR_K8_LSTAR,          CPUMCTX.msrLSTAR
    LOADGUESTMSR MSR_K6_STAR,           CPUMCTX.msrSTAR
    LOADGUESTMSR MSR_K8_SF_MASK,        CPUMCTX.msrSFMASK
    LOADGUESTMSR MSR_K8_KERNEL_GS_BASE, CPUMCTX.msrKERNELGSBASE
%endif

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     qword [rbx + VMCSCACHE.uPos], 5
%endif

    ; Save the pCtx pointer
    push    rsi

    ; Load CR2 if necessary (may be expensive as writing CR2 is a synchronizing instruction).
    mov     rbx, qword [rsi + CPUMCTX.cr2]
    mov     rdx, cr2
    cmp     rdx, rbx
    je      .skipcr2write64
    mov     cr2, rbx

.skipcr2write64:
    mov     eax, VMX_VMCS_HOST_RSP
    vmwrite rax, rsp
    ; Note: assumes success!
    ; Don't mess with ESP anymore!!!

    ; Save Guest's general purpose registers.
    mov     rax, qword [rsi + CPUMCTX.eax]
    mov     rbx, qword [rsi + CPUMCTX.ebx]
    mov     rcx, qword [rsi + CPUMCTX.ecx]
    mov     rdx, qword [rsi + CPUMCTX.edx]
    mov     rbp, qword [rsi + CPUMCTX.ebp]
    mov     r8,  qword [rsi + CPUMCTX.r8]
    mov     r9,  qword [rsi + CPUMCTX.r9]
    mov     r10, qword [rsi + CPUMCTX.r10]
    mov     r11, qword [rsi + CPUMCTX.r11]
    mov     r12, qword [rsi + CPUMCTX.r12]
    mov     r13, qword [rsi + CPUMCTX.r13]
    mov     r14, qword [rsi + CPUMCTX.r14]
    mov     r15, qword [rsi + CPUMCTX.r15]

    ; Save rdi & rsi.
    mov     rdi, qword [rsi + CPUMCTX.edi]
    mov     rsi, qword [rsi + CPUMCTX.esi]

    vmlaunch
    jmp     .vmlaunch64_done;      ; Here if vmlaunch detected a failure.

ALIGNCODE(16)
.vmlaunch64_done:
%if 0 ;fixme later - def VBOX_WITH_64ON32_IDT
    push    rdx
    mov     rdx, [rsp + 8]         ; pCtx
    lidt    [rdx + CPUMCPU.Hyper.idtr]
    pop     rdx
%endif
    jc      near .vmstart64_invalid_vmcs_ptr
    jz      near .vmstart64_start_failed

    push    rdi
    mov     rdi, [rsp + 8]         ; pCtx

    mov     qword [rdi + CPUMCTX.eax], rax
    mov     qword [rdi + CPUMCTX.ebx], rbx
    mov     qword [rdi + CPUMCTX.ecx], rcx
    mov     qword [rdi + CPUMCTX.edx], rdx
    mov     qword [rdi + CPUMCTX.esi], rsi
    mov     qword [rdi + CPUMCTX.ebp], rbp
    mov     qword [rdi + CPUMCTX.r8],  r8
    mov     qword [rdi + CPUMCTX.r9],  r9
    mov     qword [rdi + CPUMCTX.r10], r10
    mov     qword [rdi + CPUMCTX.r11], r11
    mov     qword [rdi + CPUMCTX.r12], r12
    mov     qword [rdi + CPUMCTX.r13], r13
    mov     qword [rdi + CPUMCTX.r14], r14
    mov     qword [rdi + CPUMCTX.r15], r15
    mov     rax, cr2
    mov     qword [rdi + CPUMCTX.cr2], rax

    pop     rax         ; The guest edi we pushed above
    mov     qword [rdi + CPUMCTX.edi], rax

    pop     rsi         ; pCtx (needed in rsi by the macros below)

%ifndef VBOX_WITH_AUTO_MSR_LOAD_RESTORE
    SAVEGUESTMSR MSR_K8_KERNEL_GS_BASE, CPUMCTX.msrKERNELGSBASE
    SAVEGUESTMSR MSR_K8_SF_MASK,        CPUMCTX.msrSFMASK
    SAVEGUESTMSR MSR_K6_STAR,           CPUMCTX.msrSTAR
    SAVEGUESTMSR MSR_K8_LSTAR,          CPUMCTX.msrLSTAR
%endif

%ifdef VMX_USE_CACHED_VMCS_ACCESSES
    pop     rdi         ; Saved pCache

 %ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     dword [rdi + VMCSCACHE.uPos], 7
 %endif
 %ifdef DEBUG
    mov     [rdi + VMCSCACHE.TestOut.pCache], rdi
    mov     [rdi + VMCSCACHE.TestOut.pCtx], rsi
    mov     rax, cr8
    mov     [rdi + VMCSCACHE.TestOut.cr8], rax
 %endif

    mov     ecx, [rdi + VMCSCACHE.Read.cValidEntries]
    cmp     ecx, 0  ; Can't happen
    je      .no_cached_reads
    jmp     .cached_read

ALIGN(16)
.cached_read:
    dec     rcx
    mov     eax, [rdi + VMCSCACHE.Read.aField + rcx*4]
    vmread  qword [rdi + VMCSCACHE.Read.aFieldVal + rcx*8], rax
    cmp     rcx, 0
    jnz     .cached_read
.no_cached_reads:
 %ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     dword [rdi + VMCSCACHE.uPos], 8
 %endif
%endif

    ; Restore segment registers.
    MYPOPSEGS rax

    mov     eax, VINF_SUCCESS

%ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     dword [rdi + VMCSCACHE.uPos], 9
%endif
.vmstart64_end:

%ifdef VMX_USE_CACHED_VMCS_ACCESSES
 %ifdef DEBUG
    mov     rdx, [rsp]                             ; HCPhysVmcs
    mov     [rdi + VMCSCACHE.TestOut.HCPhysVmcs], rdx
 %endif
%endif

    ; Write back the data and disable the VMCS.
    vmclear qword [rsp]  ; Pushed pVMCS
    add     rsp, 8

.vmstart64_vmxoff_end:
    ; Disable VMX root mode.
    vmxoff
.vmstart64_vmxon_failed:
%ifdef VMX_USE_CACHED_VMCS_ACCESSES
 %ifdef DEBUG
    cmp     eax, VINF_SUCCESS
    jne     .skip_flags_save

    pushf
    pop     rdx
    mov     [rdi + VMCSCACHE.TestOut.eflags], rdx
  %ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     dword [rdi + VMCSCACHE.uPos], 12
  %endif
.skip_flags_save:
 %endif
%endif
    pop     rbp
    ret


.vmstart64_invalid_vmcs_ptr:
    pop     rsi         ; pCtx (needed in rsi by the macros below)

%ifdef VMX_USE_CACHED_VMCS_ACCESSES
    pop     rdi         ; pCache
 %ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     dword [rdi + VMCSCACHE.uPos], 10
 %endif

 %ifdef DEBUG
    mov     [rdi + VMCSCACHE.TestOut.pCache], rdi
    mov     [rdi + VMCSCACHE.TestOut.pCtx], rsi
 %endif
%endif

    ; Restore segment registers.
    MYPOPSEGS rax

    ; Restore all general purpose host registers.
    mov     eax, VERR_VMX_INVALID_VMCS_PTR_TO_START_VM
    jmp     .vmstart64_end

.vmstart64_start_failed:
    pop     rsi         ; pCtx (needed in rsi by the macros below)

%ifdef VMX_USE_CACHED_VMCS_ACCESSES
    pop     rdi         ; pCache

 %ifdef DEBUG
    mov     [rdi + VMCSCACHE.TestOut.pCache], rdi
    mov     [rdi + VMCSCACHE.TestOut.pCtx], rsi
 %endif
 %ifdef VBOX_WITH_CRASHDUMP_MAGIC
    mov     dword [rdi + VMCSCACHE.uPos], 11
 %endif
%endif

    ; Restore segment registers.
    MYPOPSEGS rax

    ; Restore all general purpose host registers.
    mov     eax, VERR_VMX_UNABLE_TO_START_VM
    jmp     .vmstart64_end
ENDPROC VMXRCStartVM64


;/**
; * Prepares for and executes VMRUN (64 bits guests)
; *
; * @returns VBox status code
; * @param   HCPhysVMCB     Physical address of host VMCB       (rsp+8)
; * @param   HCPhysVMCB     Physical address of guest VMCB      (rsp+16)
; * @param   pCtx           Guest context                       (rsi)
; */
BEGINPROC SVMRCVMRun64
    push    rbp
    mov     rbp, rsp
    pushf
    DEBUG_CMOS_STACK64 30h

    ; Manual save and restore:
    ;  - General purpose registers except RIP, RSP, RAX
    ;
    ; Trashed:
    ;  - CR2 (we don't care)
    ;  - LDTR (reset to 0)
    ;  - DRx (presumably not changed at all)
    ;  - DR7 (reset to 0x400)

    ; Save the Guest CPU context pointer.
    push    rsi                             ; Push for saving the state at the end

    ; Save host fs, gs, sysenter msr etc
    mov     rax, [rbp + 8 + 8]              ; pVMCBHostPhys (64 bits physical address)
    push    rax                             ; Save for the vmload after vmrun
    vmsave

    ; Setup eax for VMLOAD
    mov     rax, [rbp + 8 + 8 + RTHCPHYS_CB]   ; pVMCBPhys (64 bits physical address)

    ; Restore Guest's general purpose registers.
    ; rax is loaded from the VMCB by VMRUN.
    mov     rbx, qword [rsi + CPUMCTX.ebx]
    mov     rcx, qword [rsi + CPUMCTX.ecx]
    mov     rdx, qword [rsi + CPUMCTX.edx]
    mov     rdi, qword [rsi + CPUMCTX.edi]
    mov     rbp, qword [rsi + CPUMCTX.ebp]
    mov     r8,  qword [rsi + CPUMCTX.r8]
    mov     r9,  qword [rsi + CPUMCTX.r9]
    mov     r10, qword [rsi + CPUMCTX.r10]
    mov     r11, qword [rsi + CPUMCTX.r11]
    mov     r12, qword [rsi + CPUMCTX.r12]
    mov     r13, qword [rsi + CPUMCTX.r13]
    mov     r14, qword [rsi + CPUMCTX.r14]
    mov     r15, qword [rsi + CPUMCTX.r15]
    mov     rsi, qword [rsi + CPUMCTX.esi]

    ; Clear the global interrupt flag & execute sti to make sure external interrupts cause a world switch.
    clgi
    sti

    ; Load guest fs, gs, sysenter msr etc
    vmload
    ; Run the VM
    vmrun

    ; rax is in the VMCB already; we can use it here.

    ; Save guest fs, gs, sysenter msr etc.
    vmsave

    ; Load host fs, gs, sysenter msr etc.
    pop     rax                     ; Pushed above
    vmload

    ; Set the global interrupt flag again, but execute cli to make sure IF=0.
    cli
    stgi

    pop     rax                     ; pCtx

    mov     qword [rax + CPUMCTX.ebx], rbx
    mov     qword [rax + CPUMCTX.ecx], rcx
    mov     qword [rax + CPUMCTX.edx], rdx
    mov     qword [rax + CPUMCTX.esi], rsi
    mov     qword [rax + CPUMCTX.edi], rdi
    mov     qword [rax + CPUMCTX.ebp], rbp
    mov     qword [rax + CPUMCTX.r8],  r8
    mov     qword [rax + CPUMCTX.r9],  r9
    mov     qword [rax + CPUMCTX.r10], r10
    mov     qword [rax + CPUMCTX.r11], r11
    mov     qword [rax + CPUMCTX.r12], r12
    mov     qword [rax + CPUMCTX.r13], r13
    mov     qword [rax + CPUMCTX.r14], r14
    mov     qword [rax + CPUMCTX.r15], r15

    mov     eax, VINF_SUCCESS

    popf
    pop     rbp
    ret
ENDPROC SVMRCVMRun64

;/**
; * Saves the guest FPU context
; *
; * @returns VBox status code
; * @param   pCtx       Guest context [rsi]
; */
BEGINPROC HMRCSaveGuestFPU64
    DEBUG_CMOS_STACK64 40h
    mov     rax, cr0
    mov     rcx, rax                    ; save old CR0
    and     rax, ~(X86_CR0_TS | X86_CR0_EM)
    mov     cr0, rax

    ; Use explicit REX prefix. See @bugref{6398}.
    o64 fxsave  [rsi + CPUMCTX.fpu]

    mov     cr0, rcx                    ; and restore old CR0 again

    mov     eax, VINF_SUCCESS
    ret
ENDPROC HMRCSaveGuestFPU64

;/**
; * Saves the guest debug context (DR0-3, DR6)
; *
; * @returns VBox status code
; * @param   pCtx       Guest context [rsi]
; */
BEGINPROC HMRCSaveGuestDebug64
    DEBUG_CMOS_STACK64 41h
    mov rax, dr0
    mov qword [rsi + CPUMCTX.dr + 0*8], rax
    mov rax, dr1
    mov qword [rsi + CPUMCTX.dr + 1*8], rax
    mov rax, dr2
    mov qword [rsi + CPUMCTX.dr + 2*8], rax
    mov rax, dr3
    mov qword [rsi + CPUMCTX.dr + 3*8], rax
    mov rax, dr6
    mov qword [rsi + CPUMCTX.dr + 6*8], rax
    mov eax, VINF_SUCCESS
    ret
ENDPROC HMRCSaveGuestDebug64

;/**
; * Dummy callback handler
; *
; * @returns VBox status code
; * @param   param1     Parameter 1 [rsp+8]
; * @param   param2     Parameter 2 [rsp+12]
; * @param   param3     Parameter 3 [rsp+16]
; * @param   param4     Parameter 4 [rsp+20]
; * @param   param5     Parameter 5 [rsp+24]
; * @param   pCtx       Guest context [rsi]
; */
BEGINPROC HMRCTestSwitcher64
    DEBUG_CMOS_STACK64 42h
    mov eax, [rsp+8]
    ret
ENDPROC HMRCTestSwitcher64


%ifdef VBOX_WITH_64ON32_IDT
;
; Trap handling.
;

;; Here follows an array of trap handler entry points, 8 byte in size.
BEGINPROC vmm64On32TrapHandlers
%macro vmm64On32TrapEntry 1
GLOBALNAME vmm64On32Trap %+ i
    db 06ah, i                          ; push imm8 - note that this is a signextended value.
    jmp   NAME(%1)
    ALIGNCODE(8)
%assign i i+1
%endmacro
%assign i 0                                 ; start counter.
    vmm64On32TrapEntry vmm64On32Trap        ; 0
    vmm64On32TrapEntry vmm64On32Trap        ; 1
    vmm64On32TrapEntry vmm64On32Trap        ; 2
    vmm64On32TrapEntry vmm64On32Trap        ; 3
    vmm64On32TrapEntry vmm64On32Trap        ; 4
    vmm64On32TrapEntry vmm64On32Trap        ; 5
    vmm64On32TrapEntry vmm64On32Trap        ; 6
    vmm64On32TrapEntry vmm64On32Trap        ; 7
    vmm64On32TrapEntry vmm64On32TrapErrCode ; 8
    vmm64On32TrapEntry vmm64On32Trap        ; 9
    vmm64On32TrapEntry vmm64On32TrapErrCode ; a
    vmm64On32TrapEntry vmm64On32TrapErrCode ; b
    vmm64On32TrapEntry vmm64On32TrapErrCode ; c
    vmm64On32TrapEntry vmm64On32TrapErrCode ; d
    vmm64On32TrapEntry vmm64On32TrapErrCode ; e
    vmm64On32TrapEntry vmm64On32Trap        ; f  (reserved)
    vmm64On32TrapEntry vmm64On32Trap        ; 10
    vmm64On32TrapEntry vmm64On32TrapErrCode ; 11
    vmm64On32TrapEntry vmm64On32Trap        ; 12
    vmm64On32TrapEntry vmm64On32Trap        ; 13
%rep (0x100 - 0x14)
    vmm64On32TrapEntry vmm64On32Trap
%endrep
ENDPROC vmm64On32TrapHandlers

;; Fake an error code and jump to the real thing.
BEGINPROC vmm64On32Trap
    push    qword [rsp]
    jmp     NAME(vmm64On32TrapErrCode)
ENDPROC vmm64On32Trap


;;
; Trap frame:
;   [rbp + 38h] = ss
;   [rbp + 30h] = rsp
;   [rbp + 28h] = eflags
;   [rbp + 20h] = cs
;   [rbp + 18h] = rip
;   [rbp + 10h] = error code (or trap number)
;   [rbp + 08h] = trap number
;   [rbp + 00h] = rbp
;   [rbp - 08h] = rax
;   [rbp - 10h] = rbx
;   [rbp - 18h] = ds
;
BEGINPROC vmm64On32TrapErrCode
    push    rbp
    mov     rbp, rsp
    push    rax
    push    rbx
    mov     ax, ds
    push    rax
    sub     rsp, 20h

    mov     ax, cs
    mov     ds, ax

%if 1
    COM64_S_NEWLINE
    COM64_S_CHAR '!'
    COM64_S_CHAR 't'
    COM64_S_CHAR 'r'
    COM64_S_CHAR 'a'
    COM64_S_CHAR 'p'
    movzx   eax, byte [rbp + 08h]
    COM64_S_DWORD_REG eax
    COM64_S_CHAR '!'
%endif

%if 0 ;; @todo Figure the offset of the CPUMCPU relative to CPUM
    sidt    [rsp]
    movsx   eax, word [rsp]
    shr     eax, 12                     ; div by  16 * 256 (0x1000).
%else
    ; hardcoded VCPU(0) for now...
    mov     rbx, [NAME(pCpumIC) wrt rip]
    mov     eax, [rbx + CPUM.offCPUMCPU0]
%endif
    push    rax                         ; Save the offset for rbp later.

    add     rbx, rax                    ; rbx = CPUMCPU

    ;
    ; Deal with recursive traps due to vmxoff (lazy bird).
    ;
    lea     rax, [.vmxoff_trap_location wrt rip]
    cmp     rax, [rbp + 18h]
    je      .not_vmx_root

    ;
    ; Save the context.
    ;
    mov     rax, [rbp - 8]
    mov     [rbx + CPUMCPU.Hyper.eax], rax
    mov     [rbx + CPUMCPU.Hyper.ecx], rcx
    mov     [rbx + CPUMCPU.Hyper.edx], rdx
    mov     rax, [rbp - 10h]
    mov     [rbx + CPUMCPU.Hyper.ebx], rax
    mov     rax, [rbp]
    mov     [rbx + CPUMCPU.Hyper.ebp], rax
    mov     rax, [rbp + 30h]
    mov     [rbx + CPUMCPU.Hyper.esp], rax
    mov     [rbx + CPUMCPU.Hyper.edi], rdi
    mov     [rbx + CPUMCPU.Hyper.esi], rsi
    mov     [rbx + CPUMCPU.Hyper.r8], r8
    mov     [rbx + CPUMCPU.Hyper.r9], r9
    mov     [rbx + CPUMCPU.Hyper.r10], r10
    mov     [rbx + CPUMCPU.Hyper.r11], r11
    mov     [rbx + CPUMCPU.Hyper.r12], r12
    mov     [rbx + CPUMCPU.Hyper.r13], r13
    mov     [rbx + CPUMCPU.Hyper.r14], r14
    mov     [rbx + CPUMCPU.Hyper.r15], r15

    mov     rax, [rbp + 18h]
    mov     [rbx + CPUMCPU.Hyper.eip], rax
    movzx   ax, [rbp + 20h]
    mov     [rbx + CPUMCPU.Hyper.cs.Sel], ax
    mov     ax, [rbp + 38h]
    mov     [rbx + CPUMCPU.Hyper.ss.Sel], ax
    mov     ax, [rbp - 18h]
    mov     [rbx + CPUMCPU.Hyper.ds.Sel], ax

    mov     rax, [rbp + 28h]
    mov     [rbx + CPUMCPU.Hyper.eflags], rax

    mov     rax, cr2
    mov     [rbx + CPUMCPU.Hyper.cr2], rax

    mov     rax, [rbp + 10h]
    mov     [rbx + CPUMCPU.Hyper.r14], rax ; r14 = error code
    movzx   eax, byte [rbp + 08h]
    mov     [rbx + CPUMCPU.Hyper.r15], rax ; r15 = trap number

    ;
    ; Finally, leave VMX root operation before trying to return to the host.
    ;
    mov     rax, cr4
    test    rax, X86_CR4_VMXE
    jz      .not_vmx_root
.vmxoff_trap_location:
    vmxoff
.not_vmx_root:

    ;
    ; Go back to the host.
    ;
    pop     rbp
    mov     dword [rbx + CPUMCPU.u32RetCode], VERR_TRPM_DONT_PANIC
    jmp     NAME(vmmRCToHostAsm)
ENDPROC vmm64On32TrapErrCode

;; We allocate the IDT here to avoid having to allocate memory separately somewhere.
ALIGNCODE(16)
GLOBALNAME vmm64On32Idt
%assign i 0
%rep 256
    dq NAME(vmm64On32Trap %+ i) - NAME(Start) ; Relative trap handler offsets.
    dq 0
%assign i (i + 1)
%endrep


 %if 0
;; For debugging purposes.
BEGINPROC vmm64On32PrintIdtr
    push    rax
    push    rsi                         ; paranoia
    push    rdi                         ; ditto
    sub rsp, 16

    COM64_S_CHAR ';'
    COM64_S_CHAR 'i'
    COM64_S_CHAR 'd'
    COM64_S_CHAR 't'
    COM64_S_CHAR 'r'
    COM64_S_CHAR '='
    sidt [rsp + 6]
    mov eax, [rsp + 8 + 4]
    COM64_S_DWORD_REG eax
    mov eax, [rsp + 8]
    COM64_S_DWORD_REG eax
    COM64_S_CHAR ':'
    movzx eax, word [rsp + 6]
    COM64_S_DWORD_REG eax
    COM64_S_CHAR '!'

    add rsp, 16
    pop     rdi
    pop     rsi
    pop     rax
    ret
ENDPROC   vmm64On32PrintIdtr
 %endif

 %if 1
;; For debugging purposes.
BEGINPROC vmm64On32DumpCmos
    push    rax
    push    rdx
    push    rcx
    push    rsi                         ; paranoia
    push    rdi                         ; ditto
    sub rsp, 16

%if 0
    mov     al, 3
    out     72h, al
    mov     al, 68h
    out     73h, al
%endif

    COM64_S_NEWLINE
    COM64_S_CHAR 'c'
    COM64_S_CHAR 'm'
    COM64_S_CHAR 'o'
    COM64_S_CHAR 's'
    COM64_S_CHAR '0'
    COM64_S_CHAR ':'

    xor     ecx, ecx
.loop1:
    mov     al, cl
    out     70h, al
    in      al, 71h
    COM64_S_BYTE_REG eax
    COM64_S_CHAR ' '
    inc     ecx
    cmp     ecx, 128
    jb      .loop1

    COM64_S_NEWLINE
    COM64_S_CHAR 'c'
    COM64_S_CHAR 'm'
    COM64_S_CHAR 'o'
    COM64_S_CHAR 's'
    COM64_S_CHAR '1'
    COM64_S_CHAR ':'
    xor     ecx, ecx
.loop2:
    mov     al, cl
    out     72h, al
    in      al, 73h
    COM64_S_BYTE_REG eax
    COM64_S_CHAR ' '
    inc     ecx
    cmp     ecx, 128
    jb      .loop2

%if 0
    COM64_S_NEWLINE
    COM64_S_CHAR 'c'
    COM64_S_CHAR 'm'
    COM64_S_CHAR 'o'
    COM64_S_CHAR 's'
    COM64_S_CHAR '2'
    COM64_S_CHAR ':'
    xor     ecx, ecx
.loop3:
    mov     al, cl
    out     74h, al
    in      al, 75h
    COM64_S_BYTE_REG eax
    COM64_S_CHAR ' '
    inc     ecx
    cmp     ecx, 128
    jb      .loop3

    COM64_S_NEWLINE
    COM64_S_CHAR 'c'
    COM64_S_CHAR 'm'
    COM64_S_CHAR 'o'
    COM64_S_CHAR 's'
    COM64_S_CHAR '3'
    COM64_S_CHAR ':'
    xor     ecx, ecx
.loop4:
    mov     al, cl
    out     72h, al
    in      al, 73h
    COM64_S_BYTE_REG eax
    COM64_S_CHAR ' '
    inc     ecx
    cmp     ecx, 128
    jb      .loop4

    COM64_S_NEWLINE
%endif

    add rsp, 16
    pop     rdi
    pop     rsi
    pop     rcx
    pop     rdx
    pop     rax
    ret
ENDPROC   vmm64On32DumpCmos
 %endif

%endif ; VBOX_WITH_64ON32_IDT



;
;
; Back to switcher code.
; Back to switcher code.
; Back to switcher code.
;
;



;;
; Trampoline for doing a call when starting the hyper visor execution.
;
; Push any arguments to the routine.
; Push the argument frame size (cArg * 4).
; Push the call target (_cdecl convention).
; Push the address of this routine.
;
;
BITS 64
ALIGNCODE(16)
BEGINPROC vmmRCCallTrampoline
%ifdef DEBUG_STUFF
    COM64_S_CHAR 'c'
    COM64_S_CHAR 't'
    COM64_S_CHAR '!'
%endif
    int3
ENDPROC vmmRCCallTrampoline


;;
; The C interface.
;
BITS 64
ALIGNCODE(16)
BEGINPROC vmmRCToHost
%ifdef DEBUG_STUFF
    push    rsi
    COM_NEWLINE
    COM_CHAR 'b'
    COM_CHAR 'a'
    COM_CHAR 'c'
    COM_CHAR 'k'
    COM_CHAR '!'
    COM_NEWLINE
    pop     rsi
%endif
    int3
ENDPROC vmmRCToHost

;;
; vmmRCToHostAsm
;
; This is an alternative entry point which we'll be using
; when the we have saved the guest state already or we haven't
; been messing with the guest at all.
;
; @param    rbp     The virtual cpu number.
; @param
;
BITS 64
ALIGNCODE(16)
BEGINPROC vmmRCToHostAsm
NAME(vmmRCToHostAsmNoReturn):
    ;; We're still in the intermediate memory context!

    ;;
    ;; Switch to compatibility mode, placing ourselves in identity mapped code.
    ;;
    jmp far [NAME(fpIDEnterTarget) wrt rip]

; 16:32 Pointer to IDEnterTarget.
NAME(fpIDEnterTarget):
    FIXUP FIX_ID_32BIT, 0, NAME(IDExitTarget) - NAME(Start)
dd  0
    FIXUP FIX_HYPER_CS, 0
dd  0

    ; We're now on identity mapped pages!
ALIGNCODE(16)
GLOBALNAME IDExitTarget
BITS 32
    DEBUG32_CHAR('1')

    ; 1. Deactivate long mode by turning off paging.
    mov     ebx, cr0
    and     ebx, ~X86_CR0_PG
    mov     cr0, ebx
    DEBUG32_CHAR('2')

    ; 2. Load intermediate page table.
    FIXUP SWITCHER_FIX_INTER_CR3_HC, 1
    mov     edx, 0ffffffffh
    mov     cr3, edx
    DEBUG32_CHAR('3')

    ; 3. Disable long mode.
    mov     ecx, MSR_K6_EFER
    rdmsr
    DEBUG32_CHAR('5')
    and     eax, ~(MSR_K6_EFER_LME)
    wrmsr
    DEBUG32_CHAR('6')

%ifndef NEED_PAE_ON_HOST
    ; 3b. Disable PAE.
    mov     eax, cr4
    and     eax, ~X86_CR4_PAE
    mov     cr4, eax
    DEBUG32_CHAR('7')
%endif

    ; 4. Enable paging.
    or      ebx, X86_CR0_PG
    mov     cr0, ebx
    jmp short just_a_jump
just_a_jump:
    DEBUG32_CHAR('8')

    ;;
    ;; 5. Jump to guest code mapping of the code and load the Hypervisor CS.
    ;;
    FIXUP FIX_ID_2_HC_NEAR_REL, 1, NAME(ICExitTarget) - NAME(Start)
    jmp near NAME(ICExitTarget)

    ;;
    ;; When we arrive at this label we're at the host mapping of the
    ;; switcher code, but with intermediate page tables.
    ;;
BITS 32
ALIGNCODE(16)
GLOBALNAME ICExitTarget
    DEBUG32_CHAR('9')
    ;DEBUG_CMOS_TRASH_AL 70h

    ; load the hypervisor data selector into ds & es
    FIXUP FIX_HYPER_DS, 1
    mov     eax, 0ffffh
    mov     ds, eax
    mov     es, eax
    DEBUG32_CHAR('a')

    FIXUP FIX_GC_CPUM_OFF, 1, 0
    mov     edx, 0ffffffffh
    CPUMCPU_FROM_CPUM_WITH_OFFSET edx, ebp

    DEBUG32_CHAR('b')
    mov     esi, [edx + CPUMCPU.Host.cr3]
    mov     cr3, esi
    DEBUG32_CHAR('c')

    ;; now we're in host memory context, let's restore regs
    FIXUP FIX_HC_CPUM_OFF, 1, 0
    mov     edx, 0ffffffffh
    CPUMCPU_FROM_CPUM_WITH_OFFSET edx, ebp
    DEBUG32_CHAR('e')

    ; restore the host EFER
    mov     ebx, edx
    mov     ecx, MSR_K6_EFER
    mov     eax, [ebx + CPUMCPU.Host.efer]
    mov     edx, [ebx + CPUMCPU.Host.efer + 4]
    DEBUG32_CHAR('f')
    wrmsr
    mov     edx, ebx
    DEBUG32_CHAR('g')

    ; activate host gdt and idt
    lgdt    [edx + CPUMCPU.Host.gdtr]
    DEBUG32_CHAR('0')
    lidt    [edx + CPUMCPU.Host.idtr]
    DEBUG32_CHAR('1')

    ; Restore TSS selector; must mark it as not busy before using ltr (!)
    ; ASSUME that this is supposed to be 'BUSY'. (saves 20-30 ticks on the T42p)
    movzx   eax, word [edx + CPUMCPU.Host.tr]          ; eax <- TR
    and     al, 0F8h                                ; mask away TI and RPL bits, get descriptor offset.
    add     eax, [edx + CPUMCPU.Host.gdtr + 2]         ; eax <- GDTR.address + descriptor offset.
    and     dword [eax + 4], ~0200h                 ; clear busy flag (2nd type2 bit)
    ltr     word [edx + CPUMCPU.Host.tr]

    ; activate ldt
    DEBUG32_CHAR('2')
    lldt    [edx + CPUMCPU.Host.ldtr]

    ; Restore segment registers
    mov     eax, [edx + CPUMCPU.Host.ds]
    mov     ds, eax
    mov     eax, [edx + CPUMCPU.Host.es]
    mov     es, eax
    mov     eax, [edx + CPUMCPU.Host.fs]
    mov     fs, eax
    mov     eax, [edx + CPUMCPU.Host.gs]
    mov     gs, eax
    ; restore stack
    lss     esp, [edx + CPUMCPU.Host.esp]

    ; Control registers.
    mov     ecx, [edx + CPUMCPU.Host.cr4]
    mov     cr4, ecx
    mov     ecx, [edx + CPUMCPU.Host.cr0]
    mov     cr0, ecx
    ;mov     ecx, [edx + CPUMCPU.Host.cr2] ; assumes this is waste of time.
    ;mov     cr2, ecx

    ; restore general registers.
    mov     edi, [edx + CPUMCPU.Host.edi]
    mov     esi, [edx + CPUMCPU.Host.esi]
    mov     ebx, [edx + CPUMCPU.Host.ebx]
    mov     ebp, [edx + CPUMCPU.Host.ebp]

    ; store the return code in eax
    DEBUG_CMOS_TRASH_AL 79h
    mov     eax, [edx + CPUMCPU.u32RetCode]
    retf
ENDPROC vmmRCToHostAsm


GLOBALNAME End
;
; The description string (in the text section).
;
NAME(Description):
    db SWITCHER_DESCRIPTION
    db 0

extern NAME(Relocate)

;
; End the fixup records.
;
BEGINDATA
    db FIX_THE_END                      ; final entry.
GLOBALNAME FixupsEnd

;;
; The switcher definition structure.
ALIGNDATA(16)
GLOBALNAME Def
    istruc VMMSWITCHERDEF
        at VMMSWITCHERDEF.pvCode,                       RTCCPTR_DEF NAME(Start)
        at VMMSWITCHERDEF.pvFixups,                     RTCCPTR_DEF NAME(Fixups)
        at VMMSWITCHERDEF.pszDesc,                      RTCCPTR_DEF NAME(Description)
        at VMMSWITCHERDEF.pfnRelocate,                  RTCCPTR_DEF NAME(Relocate)
        at VMMSWITCHERDEF.enmType,                      dd SWITCHER_TYPE
        at VMMSWITCHERDEF.cbCode,                       dd NAME(End)                        - NAME(Start)
        at VMMSWITCHERDEF.offR0ToRawMode,               dd NAME(vmmR0ToRawMode)             - NAME(Start)
        at VMMSWITCHERDEF.offRCToHost,                  dd NAME(vmmRCToHost)                - NAME(Start)
        at VMMSWITCHERDEF.offRCCallTrampoline,          dd NAME(vmmRCCallTrampoline)        - NAME(Start)
        at VMMSWITCHERDEF.offRCToHostAsm,               dd NAME(vmmRCToHostAsm)             - NAME(Start)
        at VMMSWITCHERDEF.offRCToHostAsmNoReturn,       dd NAME(vmmRCToHostAsmNoReturn)     - NAME(Start)
        ; disasm help
        at VMMSWITCHERDEF.offHCCode0,                   dd 0
        at VMMSWITCHERDEF.cbHCCode0,                    dd NAME(IDEnterTarget)              - NAME(Start)
        at VMMSWITCHERDEF.offHCCode1,                   dd NAME(ICExitTarget)               - NAME(Start)
        at VMMSWITCHERDEF.cbHCCode1,                    dd NAME(End)                        - NAME(ICExitTarget)
        at VMMSWITCHERDEF.offIDCode0,                   dd NAME(IDEnterTarget)              - NAME(Start)
        at VMMSWITCHERDEF.cbIDCode0,                    dd NAME(ICEnterTarget)              - NAME(IDEnterTarget)
        at VMMSWITCHERDEF.offIDCode1,                   dd NAME(IDExitTarget)               - NAME(Start)
        at VMMSWITCHERDEF.cbIDCode1,                    dd NAME(ICExitTarget)               - NAME(Start)
%ifdef VBOX_WITH_64ON32_IDT ; Hack! Use offGCCode to find the IDT.
        at VMMSWITCHERDEF.offGCCode,                    dd NAME(vmm64On32Idt)               - NAME(Start)
%else
        at VMMSWITCHERDEF.offGCCode,                    dd 0
%endif
        at VMMSWITCHERDEF.cbGCCode,                     dd 0

    iend