Changeset 47751 in vbox

Timestamp:

Aug 15, 2013 11:38:05 AM (11 years ago)

Author:

vboxsync

Message:

IEM: read-modified-write should have the r/w err bit set even when it happens on a not present page.

File:

• trunk/src/VBox/VMM/VMMAll/IEMAll.cpp (modified) (2 diffs)

trunk/src/VBox/VMM/VMMAll/IEMAll.cpp

@@ -3202 +3202 @@
         uErr |= X86_TRAP_PF_ID;
 
+#if 0 /* This is so much non-sense, really.  Why was it done like that? */
     /* Note! RW access callers reporting a WRITE protection fault, will clear
              the READ flag before calling.  So, read-modify-write accesses (RW)
@@ -3207 +3208 @@
     if ((fAccess & (IEM_ACCESS_TYPE_WRITE | IEM_ACCESS_TYPE_READ)) == IEM_ACCESS_TYPE_WRITE)
         uErr |= X86_TRAP_PF_RW;
+#else
+    if (fAccess & IEM_ACCESS_TYPE_WRITE)
+    {
+        if (!IEM_FULL_VERIFICATION_REM_ENABLED(pIemCpu) || !(fAccess & IEM_ACCESS_TYPE_READ))
+            uErr |= X86_TRAP_PF_RW;
+    }
+#endif
 
     return iemRaiseXcptOrInt(pIemCpu, 0, X86_XCPT_PF, IEM_XCPT_FLAGS_T_CPU_XCPT | IEM_XCPT_FLAGS_ERR | IEM_XCPT_FLAGS_CR2,