From: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Hyper-V .feat_names are, unlike hardware features, commented out and it is
not obvious why we do that. Document the current status quo.
Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Message-Id: <20181221141604.16935-1-vkuznets@xxxxxxxxxx>
Signed-off-by: Eduardo Habkost <ehabkost@xxxxxxxxxx>
---
target/i386/cpu.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 3ece83696e..2f5412592d 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -929,6 +929,13 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
*/
.no_autoenable_flags = ~0U,
},
+ /*
+ * .feat_names are commented out for Hyper-V enlightenments because we
+ * don't want to have two different ways for enabling them on QEMU command
+ * line. Some features (e.g. "hyperv_time", "hyperv_vapic", ...) require
+ * enabling several feature bits simultaneously, exposing these bits
+ * individually may just confuse guests.
+ */
[FEAT_HYPERV_EAX] = {
.type = CPUID_FEATURE_WORD,
.feat_names = {
--
2.18.0.rc1.1.g3f1ff2140
