Changeset 8111 in vbox for trunk/src/VBox/VMM

Timestamp:

Apr 17, 2008 4:02:55 PM (17 years ago)

Author:

vboxsync

Message:

The previous check for PAE was too strict.

Location:

trunk/src/VBox/VMM

Files:

• PGM.cpp (modified) (2 diffs)
• VMMAll/CPUMAllRegs.cpp (modified) (3 diffs)

trunk/src/VBox/VMM/PGM.cpp

@@ -1580 +1580 @@
     LogFlow(("PGMR3Relocate\n"));
 
+    /* Note: remove this restriction once the 32->PAE switcher works properly. */
+    if (    CPUMGetGuestCpuIdFeature(pVM, CPUMCPUIDFEATURE_PAE)
+        &&  PGMGetHostMode(pVM) <= PGMMODE_32_BIT
+        &&  !HWACCMIsEnabled(pVM))
+    {
+        CPUMClearGuestCpuIdFeature(pVM, CPUMCPUIDFEATURE_PAE);
+        LogRel(("WARNING: Can't turn on PAE when the host is in 32 bits paging mode!!\n"));
+    }
+
     /*
      * Paging stuff.
@@ -2684 +2693 @@
                 case SUPPAGINGMODE_32_BIT:
                 case SUPPAGINGMODE_32_BIT_GLOBAL:
-                    AssertFailed(); /* this switcher is not well tested!! */
                     enmShadowMode = PGMMODE_PAE;
                     enmSwitcher = VMMSWITCHER_32_TO_PAE;
-                    return PGMMODE_INVALID;
+                    break;
 
                 case SUPPAGINGMODE_PAE:

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

@@ -27 +27 @@
 #include "CPUMInternal.h"
 #include <VBox/vm.h>
-#include <VBox/pgm.h>
 #include <VBox/err.h>
 #include <VBox/dis.h>
@@ -1035 +1034 @@
                 return;
             }
-            /* Remove this restriction once the 32->PAE switcher works properly. */
-            if (PGMGetHostMode(pVM) <= PGMMODE_32_BIT)
-            {
-                LogRel(("WARNING: Can't turn on PAE when the host is in 32 bits paging mode!!\n"));
-                return;
-            }
 
             if (pVM->cpum.s.aGuestCpuIdStd[0].eax >= 1)
@@ -1075 +1068 @@
             break;
     }
+}
+
+/**
+ * Queries a CPUID feature bit.
+ *
+ * @returns boolean for feature presence
+ * @param   pVM             The VM Handle.
+ * @param   enmFeature      The feature to query.
+ */
+CPUMDECL(bool) CPUMGetGuestCpuIdFeature(PVM pVM, CPUMCPUIDFEATURE enmFeature)
+{
+    switch (enmFeature)
+    {
+        case CPUMCPUIDFEATURE_PAE:
+        {
+            if (pVM->cpum.s.aGuestCpuIdStd[0].eax >= 1)
+                return !!(pVM->cpum.s.aGuestCpuIdStd[1].edx & X86_CPUID_FEATURE_EDX_PAE);
+            break;
+        }
+
+        default:
+            AssertMsgFailed(("enmFeature=%d\n", enmFeature));
+            break;
+    }
+    return false;
 }