Changeset 42613 in vbox for trunk/src/VBox/VMM/VMMR3

Timestamp:

Aug 6, 2012 10:51:26 AM (13 years ago)

Author:

vboxsync

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

79801

Message:

VMM/VMMR3/CPUM: CFGM option for exposing CmpXchg16b if the host supports it.

File:

• trunk/src/VBox/VMM/VMMR3/CPUM.cpp (modified) (3 diffs)

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

@@ -853 +853 @@
              &pCPUM->GuestCpuIdDef.ecx, &pCPUM->GuestCpuIdDef.edx);
 
+    /** @cfgm{/CPUM/CMPXCHG16B, boolean, false}
+     * Expose CMPXCHG16B to the guest if supported by the host.
+     */
+    bool fCmpXchg16b;
+    rc = CFGMR3QueryBoolDef(pCpumCfg, "CMPXCHG16B", &fCmpXchg16b, false); AssertRCReturn(rc, rc);
 
     /* Cpuid 1 & 0x80000001:
@@ -901 +906 @@
                                     | X86_CPUID_FEATURE_ECX_SSSE3
                                   //| X86_CPUID_FEATURE_ECX_CNTXID - no L1 context id (MSR++).
-                                  //| X86_CPUID_FEATURE_ECX_CX16  - no cmpxchg16b
+                                    | (fCmpXchg16b ? X86_CPUID_FEATURE_ECX_CX16 : 0)
                                   /* ECX Bit 14 - xTPR Update Control. Processor supports changing IA32_MISC_ENABLES[bit 23]. */
                                   //| X86_CPUID_FEATURE_ECX_TPRUPDATE
@@ -914 +919 @@
         PORTABLE_DISABLE_FEATURE_BIT(1, Std[1].ecx, SSSE3, X86_CPUID_FEATURE_ECX_SSSE3);
         PORTABLE_DISABLE_FEATURE_BIT(1, Std[1].ecx, SSE3,  X86_CPUID_FEATURE_ECX_SSE3);
+        PORTABLE_DISABLE_FEATURE_BIT(1, Std[1].ecx, CX16,  X86_CPUID_FEATURE_ECX_CX16);
         PORTABLE_DISABLE_FEATURE_BIT(2, Std[1].edx, SSE2,  X86_CPUID_FEATURE_EDX_SSE2);
         PORTABLE_DISABLE_FEATURE_BIT(3, Std[1].edx, SSE,   X86_CPUID_FEATURE_EDX_SSE);