Changeset 107570 in vbox for trunk/src/VBox

Timestamp:

Jan 9, 2025 9:23:18 AM (10 days ago)

Author:

vboxsync

Message:

VMM/CPUM: Report the host CPU microcode revision number to the guest when on an amd64 host. jiraref:VBP-947

Location:

trunk/src/VBox/VMM

Files:

• VMMAll/CPUMAllMsrs.cpp (modified) (2 diffs)
• VMMR3/CPUMR3CpuId.cpp (modified) (1 diff)
• include/CPUMInternal.h (modified) (2 diffs)

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

@@ -284 +284 @@
     RT_NOREF_PV(pVCpu); RT_NOREF_PV(idMsr);
     /** @todo fake microcode update. */
-    *puValue = pRange->uValue;
+    PVM const pVM = pVCpu->CTX_SUFF(pVM);
+    if (pVM->cpum.s.GuestInfo.uMicrocodeRevision != UINT32_MAX)
+        *puValue = RT_MAKE_U64(RT_LO_U32(pRange->uValue), pVM->cpum.s.GuestInfo.uMicrocodeRevision);
+    else
+        *puValue = pRange->uValue;
     return VINF_SUCCESS;
 }
@@ -4379 +4383 @@
     RT_NOREF_PV(pVCpu); RT_NOREF_PV(idMsr);
     /** @todo Fake AMD microcode patching.  */
-    *puValue = pRange->uValue;
+    PVM const pVM = pVCpu->CTX_SUFF(pVM);
+    if (pVM->cpum.s.GuestInfo.uMicrocodeRevision != UINT32_MAX)
+        *puValue = RT_MAKE_U64(pVM->cpum.s.GuestInfo.uMicrocodeRevision, RT_HI_U32(pRange->uValue));
+    else
+        *puValue = pRange->uValue;
     return VINF_SUCCESS;
 }

trunk/src/VBox/VMM/VMMR3/CPUMR3CpuId.cpp

@@ -3396 +3396 @@
 #endif
 
+    /** @cfgm{/CPUM/GuestMicrocodeRev,32-bit}
+     * CPU microcode revision number to use.  If UINT32_MAX we use the host
+     * revision of the host CPU for the host-cpu profile and the database entry if a
+     * specific one is selected (amd64 host only). */
+    rc = CFGMR3QueryU32Def(pCpumCfg, "GuestMicrocodeRevision", &pCpum->GuestInfo.uMicrocodeRevision, UINT32_MAX);
+    AssertLogRelRCReturn(rc, rc);
+#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
+    if (   pCpum->GuestInfo.uMicrocodeRevision == UINT32_MAX
+        && strcmp(Config.szCpuName, "host") == 0)
+    {
+        rc = SUPR3QueryMicrocodeRev(&pCpum->GuestInfo.uMicrocodeRevision);
+        if (RT_FAILURE(rc))
+            pCpum->GuestInfo.uMicrocodeRevision = UINT32_MAX;
+    }
+#endif
+
     /** @cfgm{/CPUM/MSRs/[Name]/[First|Last|Type|Value|...],}
      * Overrides the guest MSRs.

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

@@ -106 +106 @@
  * @{ */
 /** The current saved state version.
- *  @todo When bumping to next version, add CPUMCTX::enmHwVirt to the saved
- *        state. */
+ *  @todo When bumping to next version, add CPUMCTX::enmHwVirt and
+ *        uMicrocodeRevision to the saved state. */
 #define CPUM_SAVED_STATE_VERSION                CPUM_SAVED_STATE_VERSION_HWVIRT_VMX_4
 /** The saved state version with u32RestoreProcCtls2 for Nested Microsoft
@@ -190 +190 @@
     uint64_t                    uScalableBusFreq;
 
+    /** The microcode revision.
+     * UINT32_MAX if the one from the CPU database entry is to be used.
+     * @see /CPUM/GuestMicrocodeRevision in CFGM. */
+    uint32_t                    uMicrocodeRevision;
+    uint32_t                    uPadding;
+
     /** Pointer to the MSR ranges (for compatibility with old hyper heap code). */
     R3PTRTYPE(PCPUMMSRRANGE)    paMsrRangesR3;