Changeset 106630 in vbox

Timestamp:

Oct 23, 2024 5:32:45 PM (5 weeks ago)

Author:

vboxsync

Message:

VMM/CPUMR3Db: bugref:10794 Fix Windows 11 24H2 guest BSOD caused by an incorrect assumption made by the guest regarding the presence of IA32_MCU_OPT_CTRL MSR.

File:

• trunk/src/VBox/VMM/VMMR3/CPUMR3Db.cpp (modified) (2 diffs)

trunk/src/VBox/VMM/VMMR3/CPUMR3Db.cpp

@@ -745 +745 @@
      * MSR_IA32_ARCH_CAPABILITIES[bit 7], see @bugref{9630}.
      * Ignore writes to this MSR and return 0 on reads.
+     *
+     * Windows 11 24H2 incorrectly reads MSR_IA32_MCU_OPT_CTRL without
+     * checking CPUID.ARCH_CAP(EAX=7h,ECX=0).EDX[bit 9] or the MSR feature
+     * bits in MSR_IA32_ARCH_CAPABILITIES[bit 18], see @bugref{10794}.
+     * Ignore wrties to this MSR and return 0 on reads.
      */
     if (pVM->cpum.s.GuestFeatures.fArchCap)
@@ -751 +756 @@
         {
             MVI(MSR_IA32_TSX_CTRL, "IA32_TSX_CTRL", 0),
+            MVI(MSR_IA32_MCU_OPT_CTRL, "IA32_MCU_OPT_CTRL", 0),
         };
         rc = cpumR3MsrApplyFudgeTable(pVM, &s_aTsxCtrl[0], RT_ELEMENTS(s_aTsxCtrl));