[aandrejevic] 69427: [FAST486] Reading/writing to memory should #SS(0) when the segment is the stack segment, and #GP(0) otherwise. It should never generate #NP.

Author: aandrejevic
Date: Fri Oct  2 15:11:24 2015
New Revision: 69427

URL: http://svn.reactos.org/svn/reactos?rev=69427&view=rev
Log:
[FAST486]
Reading/writing to memory should #SS(0) when the segment is the stack segment,
and #GP(0) otherwise. It should never generate #NP.


Modified:
    trunk/reactos/lib/fast486/common.c

Modified: trunk/reactos/lib/fast486/common.c
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/lib/fast486/common.c?rev=6…
==============================================================================
--- trunk/reactos/lib/fast486/common.c	[iso-8859-1] (original)
+++ trunk/reactos/lib/fast486/common.c	[iso-8859-1] Fri Oct  2 15:11:24 2015
@@ -42,6 +42,8 @@
 {
     ULONG LinearAddress;
     PFAST486_SEG_REG CachedDescriptor;
+    FAST486_EXCEPTIONS Exception = SegmentReg != FAST486_REG_SS
+                                   ? FAST486_EXCEPTION_GP : FAST486_EXCEPTION_SS;
 
     ASSERT(SegmentReg < FAST486_NUM_SEG_REGS);
 
@@ -53,7 +55,7 @@
         if ((Offset + Size - 1) > CachedDescriptor->Limit)
         {
             /* Read beyond limit */
-            Fast486Exception(State, FAST486_EXCEPTION_GP);
+            Fast486Exception(State, Exception);
             return FALSE;
         }
     }
@@ -62,7 +64,7 @@
         if (Offset < CachedDescriptor->Limit)
         {
             /* Read beyond limit */
-            Fast486Exception(State, FAST486_EXCEPTION_GP);
+            Fast486Exception(State, Exception);
             return FALSE;
         }
     }
@@ -74,14 +76,14 @@
 
         if (!CachedDescriptor->Present)
         {
-            Fast486Exception(State, FAST486_EXCEPTION_NP);
+            Fast486Exception(State, Exception);
             return FALSE;
         }
 
         if ((!InstFetch && (CachedDescriptor->Rpl >
CachedDescriptor->Dpl))
             || (Fast486GetCurrentPrivLevel(State) > CachedDescriptor->Dpl))
         {
-            Fast486Exception(State, FAST486_EXCEPTION_GP);
+            Fast486Exception(State, Exception);
             return FALSE;
         }
 
@@ -90,7 +92,7 @@
             if (!CachedDescriptor->Executable)
             {
                 /* Data segment not executable */
-                Fast486Exception(State, FAST486_EXCEPTION_GP);
+                Fast486Exception(State, Exception);
                 return FALSE;
             }
         }
@@ -99,7 +101,7 @@
             if (CachedDescriptor->Executable &&
(!CachedDescriptor->ReadWrite))
             {
                 /* Code segment not readable */
-                Fast486Exception(State, FAST486_EXCEPTION_GP);
+                Fast486Exception(State, Exception);
                 return FALSE;
             }
         }
@@ -166,6 +168,8 @@
 {
     ULONG LinearAddress;
     PFAST486_SEG_REG CachedDescriptor;
+    FAST486_EXCEPTIONS Exception = SegmentReg != FAST486_REG_SS
+                                   ? FAST486_EXCEPTION_GP : FAST486_EXCEPTION_SS;
 
     ASSERT(SegmentReg < FAST486_NUM_SEG_REGS);
 
@@ -177,7 +181,7 @@
         if ((Offset + Size - 1) > CachedDescriptor->Limit)
         {
             /* Write beyond limit */
-            Fast486Exception(State, FAST486_EXCEPTION_GP);
+            Fast486Exception(State, Exception);
             return FALSE;
         }
     }
@@ -185,8 +189,8 @@
     {
         if (Offset < CachedDescriptor->Limit)
         {
-            /* Read beyond limit */
-            Fast486Exception(State, FAST486_EXCEPTION_GP);
+            /* Write beyond limit */
+            Fast486Exception(State, Exception);
             return FALSE;
         }
     }
@@ -198,27 +202,27 @@
 
         if (!CachedDescriptor->Present)
         {
-            Fast486Exception(State, FAST486_EXCEPTION_NP);
+            Fast486Exception(State, Exception);
             return FALSE;
         }
 
         if ((CachedDescriptor->Rpl > CachedDescriptor->Dpl)
             || (Fast486GetCurrentPrivLevel(State) > CachedDescriptor->Dpl))
         {
-            Fast486Exception(State, FAST486_EXCEPTION_GP);
+            Fast486Exception(State, Exception);
             return FALSE;
         }
 
         if (CachedDescriptor->Executable)
         {
             /* Code segment not writable */
-            Fast486Exception(State, FAST486_EXCEPTION_GP);
+            Fast486Exception(State, Exception);
             return FALSE;
         }
         else if (!CachedDescriptor->ReadWrite)
         {
             /* Data segment not writeable */
-            Fast486Exception(State, FAST486_EXCEPTION_GP);
+            Fast486Exception(State, Exception);
             return FALSE;
         }
     }