Changeset 14131 in vbox for trunk/src/VBox

Timestamp:

Nov 12, 2008 12:46:26 PM (16 years ago)

Author:

vboxsync

Message:

PGM: Prevent fixated mappings from crossing a PD boundrary (guest+shadow PAE).

Location:

trunk/src/VBox/VMM

Files:

• PGMMap.cpp (modified) (2 diffs)
• VMMAll/PGMAllBth.h (modified) (4 diffs)

trunk/src/VBox/VMM/PGMMap.cpp

@@ -356 +356 @@
 
     /*
+     * In PAE / PAE mode, make sure we don't cross page directories.
+     */
+    if (    (   pVM->pgm.s.enmGuestMode  == PGMMODE_PAE
+             || pVM->pgm.s.enmGuestMode  == PGMMODE_PAE_NX)
+        &&  (   pVM->pgm.s.enmShadowMode == PGMMODE_PAE
+             || pVM->pgm.s.enmShadowMode == PGMMODE_PAE_NX))
+    {
+        unsigned iPdptBase = GCPtrBase >> X86_PDPT_SHIFT;
+        unsigned iPdptLast = (GCPtrBase + cb - 1) >> X86_PDPT_SHIFT;
+        if (iPdptBase != iPdptLast)
+        {
+            LogRel(("PGMR3MappingsFix: Crosses PD boundrary; iPdptBase=%#x iPdptLast=%#x (GCPtrBase=%RGv cb=%#zx). The guest should retry.\n",
+                    iPdptBase, iPdptLast, GCPtrBase, cb));
+            return VERR_PGM_MAPPINGS_FIX_CONFLICT;
+        }
+    }
+
+    /*
      * Loop the mappings and check that they all agree on their new locations.
      */
@@ -977 +995 @@
          * Note that we do not support mappings at the very end of the
          * address space since that will break our GCPtrEnd assumptions.
+         * Nor do we support mappings crossing page directories.
          */
         const unsigned  cPTs = pMapping->cb >> X86_PD_PAE_SHIFT;

trunk/src/VBox/VMM/VMMAll/PGMAllBth.h

@@ -3280 +3280 @@
                         /* It's fixed, just skip the mapping. */
                         const unsigned cPTs = pMapping->cb >> GST_PD_SHIFT;
+                        Assert(PGM_GST_TYPE == PGM_TYPE_32BIT || (iPD + cPTs - 1) / X86_PG_PAE_ENTRIES == iPD / X86_PG_PAE_ENTRIES);
                         iPD += cPTs - 1;
 #   if PGM_SHW_TYPE != PGM_GST_TYPE /* SHW==PAE && GST==32BIT */
@@ -3285 +3286 @@
 #   else
                         pPDEDst += cPTs;
-                        /** @todo Assert on / deal with  cross PD mappings in PAE/PAE mode! */
 #   endif
                         pMapping = pMapping->CTX_SUFF(pNext);
@@ -3491 +3491 @@
 
                 /* advance. */
+                Assert(PGM_GST_TYPE == PGM_TYPE_32BIT || (iPD + cPTs - 1) / X86_PG_PAE_ENTRIES == iPD / X86_PG_PAE_ENTRIES);
                 iPD += cPTs - 1;
 #   if PGM_SHW_TYPE != PGM_GST_TYPE /* SHW==PAE && GST==32BIT */
@@ -3496 +3497 @@
 #   else
                 pPDEDst += cPTs;
-                /** @todo Assert on / deal with  cross PD mappings in PAE/PAE mode! */
 #   endif
 #   if PGM_GST_TYPE != PGM_SHW_TYPE