Changeset 22169 in vbox for trunk/src

Timestamp:

Aug 11, 2009 2:58:45 PM (15 years ago)

Author:

vboxsync

Message:

Avoid incorrect reuse of big pages: take the NX bit into account too.

File:

• trunk/src/VBox/VMM/VMMAll/PGMAllBth.h (modified) (2 diffs)

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

@@ -2599 +2599 @@
             PGMPOOLACCESS enmAccess;
 
+# if PGM_WITH_NX(PGM_GST_TYPE, PGM_SHW_TYPE)
+            const bool fNoExecuteBitValid = !!(CPUMGetGuestEFER(pVCpu) & MSR_K6_EFER_NXE);
+            const bool fNoExecute = fNoExecuteBitValid && PdeSrc.n.u1NoExecute;
+# else
+            const bool fNoExecute = false;
+# endif
+
             GCPhys = GST_GET_PDE_BIG_PG_GCPHYS(PdeSrc);
 # if PGM_SHW_TYPE == PGM_TYPE_PAE && PGM_GST_TYPE == PGM_TYPE_32BIT
@@ -2608 +2615 @@
             {
                 if (PdeSrc.n.u1Write)
-                    enmAccess = PGMPOOLACCESS_USER_RW;
+                    enmAccess = (fNoExecute) ? PGMPOOLACCESS_USER_RW_NX : PGMPOOLACCESS_USER_RW;
                 else
-                    enmAccess = PGMPOOLACCESS_USER_R;
+                    enmAccess = (fNoExecute) ? PGMPOOLACCESS_USER_R_NX : PGMPOOLACCESS_USER_R;
             }
             else
             {
                 if (PdeSrc.n.u1Write)
-                    enmAccess = PGMPOOLACCESS_SUPERVISOR_RW;
+                    enmAccess = (fNoExecute) ? PGMPOOLACCESS_SUPERVISOR_RW_NX : PGMPOOLACCESS_SUPERVISOR_RW;
                 else
-                    enmAccess = PGMPOOLACCESS_SUPERVISOR_R;
+                    enmAccess = (fNoExecute) ? PGMPOOLACCESS_SUPERVISOR_R_NX : PGMPOOLACCESS_SUPERVISOR_R;
             }
             rc = pgmPoolAllocEx(pVM, GCPhys, BTH_PGMPOOLKIND_PT_FOR_BIG, enmAccess, pShwPde->idx, iPDDst, &pShwPage);