Changeset 92481 in vbox for trunk/src/VBox/VMM/VMMAll

Timestamp:

Nov 17, 2021 2:14:56 PM (3 years ago)

Author:

vboxsync

Message:

VMM: Nested VMX: bugref:10092 Comment clarifying disappearing of bit 7 of MSR_IA32_VMX_EPT_VPID_CAP.

File:

• trunk/src/VBox/VMM/VMMAll/PGMAllGstSlatEpt.cpp.h (modified) (1 diff)

trunk/src/VBox/VMM/VMMAll/PGMAllGstSlatEpt.cpp.h

@@ -115 +115 @@
      * Do the walk.
      */
-    int const rc2 = pgmGstGetEptPML4PtrEx(pVCpu, &pGstWalk->pPml4);
-    if (RT_SUCCESS(rc2))
-    { /* likely */ }
-    else
-        return PGM_GST_SLAT_NAME_EPT(WalkReturnBadPhysAddr)(pVCpu, pWalk, 4, rc2);
-
     uint64_t fEffective;
+    {
+        /*
+         * Start with reading the EPT PML4E pointer.
+         *
+         * We currently only support 4 level EPT paging.
+         * EPT 5 level paging was documented at some point (bit 7 of MSR_IA32_VMX_EPT_VPID_CAP)
+         * but for some reason seems to have been removed from subsequent specs.
+         */
+        int const rc = pgmGstGetEptPML4PtrEx(pVCpu, &pGstWalk->pPml4);
+        if (RT_SUCCESS(rc))
+        { /* likely */ }
+        else
+            return PGM_GST_SLAT_NAME_EPT(WalkReturnBadPhysAddr)(pVCpu, pWalk, 4, rc);
+    }
     {
         /*