Changeset 107931 in vbox for trunk

Timestamp:

Jan 24, 2025 10:00:36 AM (3 months ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

167166

Message:

VMM/NEM-win: Only export & import IA32_SPEC_CTRL if the host supports it and we're exposing the register to the guest. (AMD regression from r167064.) jiraref:VBP-947 bugref:10738

Location:

trunk/src/VBox/VMM

Files:

• VMMAll/NEMAllNativeTemplate-win.cpp.h (modified) (2 diffs)
• VMMR3/NEMR3Native-win.cpp (modified) (1 diff)
• include/NEMInternal.h (modified) (1 diff)

trunk/src/VBox/VMM/VMMAll/NEMAllNativeTemplate-win.cpp.h

@@ -347 +347 @@
             ADD_REG64(WHvX64RegisterMsrMtrrFix4kF0000,  pCtxMsrs->msr.MtrrFix4K_F0000);
             ADD_REG64(WHvX64RegisterMsrMtrrFix4kF8000,  pCtxMsrs->msr.MtrrFix4K_F8000);
-            if (pVM->nem.s.fSpeculationControl)
+            if (pVM->nem.s.fDoIa32SpecCtrl)
                 ADD_REG64(WHvX64RegisterSpecCtrl, pCtxMsrs->msr.SpecCtrl);
 
@@ -621 +621 @@
         aenmNames[iReg++] = WHvX64RegisterMsrMtrrFix4kF0000;
         aenmNames[iReg++] = WHvX64RegisterMsrMtrrFix4kF8000;
-        if (pVM->nem.s.fSpeculationControl)
+        if (pVM->nem.s.fDoIa32SpecCtrl)
             aenmNames[iReg++] = WHvX64RegisterSpecCtrl;
         /** @todo look for HvX64RegisterIa32MiscEnable and HvX64RegisterIa32FeatureControl? */

trunk/src/VBox/VMM/VMMR3/NEMR3Native-win.cpp

@@ -1539 +1539 @@
     AssertReturn(!pVM->nem.s.fCreatedEmts, VERR_WRONG_ORDER);
     AssertReturn(pVM->bMainExecutionEngine == VM_EXEC_ENGINE_NATIVE_API, VERR_WRONG_ORDER);
+
+    /*
+     * Determine whether we can and should export/import IA32_SPEC_CTRL.
+     */
+    pVM->nem.s.fDoIa32SpecCtrl = pVM->nem.s.fSpeculationControl
+                              && g_CpumHostFeatures.s.fSpecCtrlMsr
+                              && pVM->cpum.ro.GuestFeatures.fSpecCtrlMsr;
 
     /*

trunk/src/VBox/VMM/include/NEMInternal.h

@@ -265 +265 @@
     /** Copy of WHV_CAPABILITY_FEATURES::SpeculationControl. */
     bool                        fSpeculationControl : 1;
+    /** Whether to export/import IA32_SPEC_CTRL. */
+    bool                        fDoIa32SpecCtrl : 1;
 #  ifdef NEM_WIN_WITH_A20
     /** Set if we've started more than one CPU and cannot mess with A20. */