[PATCH RFC 09/22] i386: add reserved FEAT_HYPERV_ECX CPUID leaf

[Vitaly Kuznetsov <vkuznets@redhat.com>]

As a preparation to expanding Hyper-V CPU features early, add
reserved FEAT_HYPERV_ECX CPUID leaf.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
 target/i386/cpu.c | 5 +++++
 target/i386/cpu.h | 1 +
 target/i386/kvm.c | 2 ++
 3 files changed, 8 insertions(+)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index ef3c672cf415..70588571ccb1 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -974,6 +974,11 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
         },
         .cpuid = { .eax = 0x40000003, .reg = R_EBX, },
     },
+    [FEAT_HYPERV_ECX] = {
+        .type = CPUID_FEATURE_WORD,
+        /* reserved */
+        .cpuid = { .eax = 0x40000003, .reg = R_ECX, },
+    },
     [FEAT_HYPERV_EDX] = {
         .type = CPUID_FEATURE_WORD,
         .feat_names = {
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 095d0bf75493..39e0e89aa41f 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -521,6 +521,7 @@ typedef enum FeatureWord {
     FEAT_KVM_HINTS,     /* CPUID[4000_0001].EDX */
     FEAT_HYPERV_EAX,    /* CPUID[4000_0003].EAX */
     FEAT_HYPERV_EBX,    /* CPUID[4000_0003].EBX */
+    FEAT_HYPERV_ECX,    /* CPUID[4000_0003].ECX */
     FEAT_HYPERV_EDX,    /* CPUID[4000_0003].EDX */
     FEAT_HV_RECOMM_EAX, /* CPUID[4000_0004].EAX */
     FEAT_HV_NESTED_EAX, /* CPUID[4000_000A].EAX */
diff --git a/target/i386/kvm.c b/target/i386/kvm.c
index 96ac719adca1..259be2d514dd 100644
--- a/target/i386/kvm.c
+++ b/target/i386/kvm.c
@@ -1251,6 +1251,7 @@ static int hyperv_handle_properties(CPUState *cs,
         if (c) {
             env->features[FEAT_HYPERV_EAX] = c->eax;
             env->features[FEAT_HYPERV_EBX] = c->ebx;
+            env->features[FEAT_HYPERV_ECX] = c->ecx;
             env->features[FEAT_HYPERV_EDX] = c->edx;
         }
 
@@ -1350,6 +1351,7 @@ static int hyperv_handle_properties(CPUState *cs,
     c->function = HV_CPUID_FEATURES;
     c->eax = env->features[FEAT_HYPERV_EAX];
     c->ebx = env->features[FEAT_HYPERV_EBX];
+    c->ecx = env->features[FEAT_HYPERV_ECX];
     c->edx = env->features[FEAT_HYPERV_EDX];
 
     c = &cpuid_ent[cpuid_i++];
-- 
2.25.4