Author: aandrejevic
Date: Wed Nov 20 10:48:26 2013
New Revision: 61057
URL: http://svn.reactos.org/svn/reactos?rev=61057&view=rev
Log:
[FAST486]
Read the LDT instead of the GDT when the table indicator is set.
Modified:
branches/ntvdm/lib/fast486/common.h
branches/ntvdm/lib/fast486/common.inl
Modified: branches/ntvdm/lib/fast486/common.h
URL:
http://svn.reactos.org/svn/reactos/branches/ntvdm/lib/fast486/common.h?rev=61057&r1=61056&r2=61057&view=diff
==============================================================================
--- branches/ntvdm/lib/fast486/common.h [iso-8859-1] (original)
+++ branches/ntvdm/lib/fast486/common.h [iso-8859-1] Wed Nov 20 10:48:26 2013
@@ -37,6 +37,7 @@
#define GET_SEGMENT_RPL(s) ((s) & 3)
#define GET_SEGMENT_INDEX(s) ((s) & 0xFFF8)
+#define SEGMENT_TABLE_INDICATOR (1 << 2)
#define EXCEPTION_HAS_ERROR_CODE(x) (((x) == 8) || ((x) >= 10 && (x) <= 14))
#define NO_LOCK_PREFIX() if (State->PrefixFlags & FAST486_PREFIX_LOCK)\
Modified: branches/ntvdm/lib/fast486/common.inl
URL:
http://svn.reactos.org/svn/reactos/branches/ntvdm/lib/fast486/common.inl?rev=61057&r1=61056&r2=61057&view=diff
==============================================================================
--- branches/ntvdm/lib/fast486/common.inl [iso-8859-1] (original)
+++ branches/ntvdm/lib/fast486/common.inl [iso-8859-1] Wed Nov 20
10:48:26 2013
@@ -399,22 +399,45 @@
/* Check for protected mode */
if ((State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_PE) &&
!State->Flags.Vm)
{
- /* Make sure the GDT contains the entry */
- if (GET_SEGMENT_INDEX(Selector) >= (State->Gdtr.Size + 1))
- {
- Fast486Exception(State, FAST486_EXCEPTION_GP);
- return FALSE;
- }
-
- /* Read the GDT */
- if (!Fast486ReadLinearMemory(State,
- State->Gdtr.Address
- + GET_SEGMENT_INDEX(Selector),
- &GdtEntry,
- sizeof(GdtEntry)))
- {
- /* Exception occurred */
- return FALSE;
+ if (!(Selector & SEGMENT_TABLE_INDICATOR))
+ {
+ /* 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;
+ }
+ }
+ else
+ {
+ /* Make sure the LDT contains the entry */
+ if (GET_SEGMENT_INDEX(Selector) >= (State->Ldtr.Size + 1))
+ {
+ Fast486ExceptionWithErrorCode(State, FAST486_EXCEPTION_GP,
Selector);
+ return FALSE;
+ }
+
+ /* Read the LDT */
+ if (!Fast486ReadLinearMemory(State,
+ State->Ldtr.Address
+ + GET_SEGMENT_INDEX(Selector),
+ &GdtEntry,
+ sizeof(GdtEntry)))
+ {
+ /* Exception occurred */
+ return FALSE;
+ }
}
if (Segment == FAST486_REG_SS)
@@ -503,7 +526,6 @@
Fast486ExceptionWithErrorCode(State,
FAST486_EXCEPTION_GP, Selector);
return FALSE;
}
-
}
/* Update CPL */
