cpuid: handle CPUID(0x80000006): L2 cache information

Fixes: #7341

Signed-off-by: Andrei Vagin <avagin@gmail.com>

pkg/cpuid/cpuid_amd64_test.go

@@ -56,6 +56,23 @@ func TestHostFeatureSet(t *testing.T) {
 	}
 }
 
+func TestFixedExtendedState(t *testing.T) {
+	hostFeatures := HostFeatureSet()
+	fixedFeatures := hostFeatures.Fixed()
+	for i, allowed := range allowedBasicFunctions {
+		if !allowed {
+			continue
+		}
+		in := In{Eax: uint32(i) + uint32(extendedStart)}
+		h := hostFeatures.Query(in)
+		f := fixedFeatures.Query(in)
+		if h != f {
+			t.Errorf("native: %x fixed: %x", h, f)
+		}
+	}
+
+}
+
 func TestHasFeature(t *testing.T) {
 	if !justFPU.HasFeature(X86FeatureFPU) {
 		t.Errorf("HasFeature failed, %q should contain %v", justFPU.FlagString(), X86FeatureFPU)

pkg/cpuid/native_amd64.go

@@ -62,10 +62,15 @@ const xSaveInfoNumLeaves = 64 // Maximum number of xSaveInfo leaves.
 
 // The "extended" functions.
 const (
-	extendedStart        cpuidFunction = 0x80000000
-	extendedFunctionInfo cpuidFunction = extendedStart + 0 // Returns highest available extended function in eax.
-	extendedFeatures                   = extendedStart + 1 // Returns some extended feature bits in edx and ecx.
-	addressSizes                       = extendedStart + 8 // Physical and virtual address sizes.
+	extendedStart         cpuidFunction = 0x80000000
+	extendedFunctionInfo  cpuidFunction = extendedStart + 0 // Returns highest available extended function in eax.
+	extendedFeatures                    = extendedStart + 1 // Returns some extended feature bits in edx and ecx.
+	processorBrandString2               = extendedStart + 2 // Processor Name String Identifier.
+	processorBrandString3               = extendedStart + 3 // Processor Name String Identifier.
+	processorBrandString4               = extendedStart + 4 // Processor Name String Identifier.
+	l1CacheAndTLBInfo                   = extendedStart + 5 // Returns L2 cache information.
+	l2CacheInfo                         = extendedStart + 6 // Returns L2 cache information.
+	addressSizes                        = extendedStart + 8 // Physical and virtual address sizes.
 )
 
 var allowedBasicFunctions = [...]bool{
@@ -78,9 +83,14 @@ var allowedBasicFunctions = [...]bool{
 }
 
 var allowedExtendedFunctions = [...]bool{
-	extendedFunctionInfo - extendedStart: true,
-	extendedFeatures - extendedStart:     true,
-	addressSizes - extendedStart:         true,
+	extendedFunctionInfo - extendedStart:  true,
+	extendedFeatures - extendedStart:      true,
+	addressSizes - extendedStart:          true,
+	processorBrandString2 - extendedStart: true,
+	processorBrandString3 - extendedStart: true,
+	processorBrandString4 - extendedStart: true,
+	l1CacheAndTLBInfo - extendedStart:     true,
+	l2CacheInfo - extendedStart:           true,
 }
 
 // Function executes a CPUID function.
@@ -108,6 +118,8 @@ func (i *In) normalize() {
 	switch cpuidFunction(i.Eax) {
 	case vendorID, featureInfo, intelCacheDescriptors, extendedFunctionInfo, extendedFeatures:
 		i.Ecx = 0 // Ignore.
+	case processorBrandString2, processorBrandString3, processorBrandString4, l1CacheAndTLBInfo, l2CacheInfo:
+		i.Ecx = 0 // Ignore.
 	case intelDeterministicCacheParams, extendedFeatureInfo:
 		// Preserve i.Ecx.
 	}