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[FAST486]

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Fix the emulation of the Local Descriptor Table.


svn path=/branches/ntvdm/; revision=61268
This commit is contained in:
Aleksandar Andrejevic 2013-12-14 02:13:01 +00:00
parent aac5c65456
commit 18b844dffa
3 changed files with 80 additions and 47 deletions
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108
lib/fast486/opgroups.c
View file

@ -1702,10 +1702,8 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupFF)
FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0F00)
{
UCHAR TableReg[6];
FAST486_MOD_REG_RM ModRegRm;
BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
FAST486_SEG_REGS Segment = FAST486_REG_DS;
NO_LOCK_PREFIX();
TOGGLE_ADSIZE(AddressSize);
@ -1716,36 +1714,23 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0F00)
return FALSE;
}
/* Check for the segment override */
if (State->PrefixFlags & FAST486_PREFIX_SEG)
{
/* Use the override segment instead */
Segment = State->SegmentOverride;
}
/* Check which operation this is */
switch (ModRegRm.Register)
{
/* SLDT */
case 0:
{
if (!ModRegRm.Memory)
/* Not recognized in real mode or virtual 8086 mode */
if (!(State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_PE)
|| State->Flags.Vm)
{
/* The second operand must be a memory location */
Fast486Exception(State, FAST486_EXCEPTION_UD);
return FALSE;
}
/* Fill the 6-byte table register */
RtlCopyMemory(TableReg, &State->Ldtr.Size, sizeof(USHORT));
RtlCopyMemory(&TableReg[sizeof(USHORT)], &State->Ldtr.Address, sizeof(ULONG));
/* Store the LDTR */
return Fast486WriteMemory(State,
Segment,
ModRegRm.MemoryAddress,
TableReg,
sizeof(TableReg));
return Fast486WriteModrmWordOperands(State,
&ModRegRm,
FALSE,
State->Ldtr.Selector);
}
/* STR */
@ -1767,6 +1752,16 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0F00)
/* LLDT */
case 2:
{
USHORT Selector;
FAST486_SYSTEM_DESCRIPTOR GdtEntry;
/* Not recognized in real mode or virtual 8086 mode */
if (!(State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_PE)
|| State->Flags.Vm)
{
Fast486Exception(State, FAST486_EXCEPTION_UD);
}
/* This is a privileged instruction */
if (Fast486GetCurrentPrivLevel(State) != 0)
{
@ -1774,28 +1769,57 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0F00)
return FALSE;
}
if (!ModRegRm.Memory)
{
/* The second operand must be a memory location */
Fast486Exception(State, FAST486_EXCEPTION_UD);
return FALSE;
}
/* Read the new LDTR */
if (!Fast486ReadMemory(State,
Segment,
ModRegRm.MemoryAddress,
FALSE,
TableReg,
sizeof(TableReg)))
if (!Fast486ReadModrmWordOperands(State,
&ModRegRm,
NULL,
&Selector))
{
/* Exception occurred */
return FALSE;
}
/* Load the new LDT */
State->Ldtr.Size = *((PUSHORT)TableReg);
State->Ldtr.Address = *((PULONG)&TableReg[sizeof(USHORT)]);
/* Make sure the GDT contains the entry */
if (GET_SEGMENT_INDEX(Selector) >= (State->Gdtr.Size + 1))
{
Fast486ExceptionWithErrorCode(State, FAST486_EXCEPTION_GP, Selector);
return FALSE;
}
/* Read the GDT */
if (!Fast486ReadLinearMemory(State,
State->Gdtr.Address
+ GET_SEGMENT_INDEX(Selector),
&GdtEntry,
sizeof(GdtEntry)))
{
/* Exception occurred */
return FALSE;
}
if (GET_SEGMENT_INDEX(Selector) == 0)
{
Fast486Exception(State, FAST486_EXCEPTION_GP);
return FALSE;
}
if (!GdtEntry.Present)
{
Fast486ExceptionWithErrorCode(State, FAST486_EXCEPTION_NP, Selector);
return FALSE;
}
if (GdtEntry.Signature != FAST486_LDT_SIGNATURE)
{
/* This is not a LDT descriptor */
Fast486ExceptionWithErrorCode(State, FAST486_EXCEPTION_GP, Selector);
return FALSE;
}
/* Update the LDTR */
State->Ldtr.Selector = Selector;
State->Ldtr.Base = GdtEntry.Base | (GdtEntry.BaseMid << 16) | (GdtEntry.BaseHigh << 24);
State->Ldtr.Limit = GdtEntry.Limit | (GdtEntry.LimitHigh << 16);
if (GdtEntry.Granularity) State->Ldtr.Limit <<= 12;
return TRUE;
}
@ -1804,7 +1828,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0F00)
case 3:
{
USHORT Selector;
FAST486_TSS_DESCRIPTOR GdtEntry;
FAST486_SYSTEM_DESCRIPTOR GdtEntry;
/* Not recognized in real mode or virtual 8086 mode */
if (!(State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_PE)
@ -1930,7 +1954,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0F00)
else
{
/* Make sure the LDT contains the entry */
if (GET_SEGMENT_INDEX(Selector) >= (State->Ldtr.Size + 1))
if (GET_SEGMENT_INDEX(Selector) >= (State->Ldtr.Limit + 1))
{
/* Clear ZF */
State->Flags.Zf = FALSE;
@ -1939,7 +1963,7 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0F00)
/* Read the LDT */
if (!Fast486ReadLinearMemory(State,
State->Ldtr.Address
State->Ldtr.Base
+ GET_SEGMENT_INDEX(Selector),
&GdtEntry,
sizeof(GdtEntry)))