The new option will allow slow emulated features (the ones returned by
GET_EMULATED_CPUID) to be enabled. We don't want to allow them to be
enabled by accident, so they will be enabled only if emulation is
explicitly allowed by the user.
Use "x-" prefix on the property name, to document that it is not
supposed to be supported forever, and intended for developers who want
to test GET_EMULATED_CPUID.
Signed-off-by: Eduardo Habkost <ehabkost@xxxxxxxxxx>
---
Changes v1 -> v2:
* Rename property to x-allow-emulation
---
target-i386/cpu-qom.h | 3 +++
target-i386/cpu.c | 18 ++++++++++++++----
2 files changed, 17 insertions(+), 4 deletions(-)
diff --git a/target-i386/cpu-qom.h b/target-i386/cpu-qom.h
index 385b81f..831f7bf 100644
--- a/target-i386/cpu-qom.h
+++ b/target-i386/cpu-qom.h
@@ -74,6 +74,8 @@ typedef struct X86CPUClass {
* @migratable: If set, only migratable flags will be accepted when "enforce"
* mode is used, and only migratable flags will be included in the "host"
* CPU model.
+ * @allow_emulation: If set, accelerator-specific code will allow emulated
+ * features to be enabled.
*
* An x86 CPU.
*/
@@ -91,6 +93,7 @@ typedef struct X86CPU {
bool check_cpuid;
bool enforce_cpuid;
bool migratable;
+ bool allow_emulation;
/* if true the CPUID code directly forward host cache leaves to the guest */
bool cache_info_passthrough;
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 1395473..cf6ab59 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -1280,7 +1280,8 @@ static void host_x86_cpu_class_init(ObjectClass *oc, void *data)
}
static uint32_t x86_cpu_get_supported_feature_word(FeatureWord w,
- bool migratable_only);
+ bool migratable_only,
+ bool allow_emulation);
static void host_x86_cpu_initfn(Object *obj)
{
@@ -1297,7 +1298,8 @@ static void host_x86_cpu_initfn(Object *obj)
for (w = 0; w < FEATURE_WORDS; w++) {
env->features[w] =
- x86_cpu_get_supported_feature_word(w, cpu->migratable);
+ x86_cpu_get_supported_feature_word(w, cpu->migratable,
+ cpu->allow_emulation);
}
object_property_set_bool(OBJECT(cpu), true, "pmu", &error_abort);
}
@@ -1887,7 +1889,8 @@ CpuDefinitionInfoList *arch_query_cpu_definitions(Error **errp)
}
static uint32_t x86_cpu_get_supported_feature_word(FeatureWord w,
- bool migratable_only)
+ bool migratable_only,
+ bool allow_emulation)
{
FeatureWordInfo *wi = &feature_word_info[w];
uint32_t r;
@@ -1896,6 +1899,11 @@ static uint32_t x86_cpu_get_supported_feature_word(FeatureWord w,
r = kvm_arch_get_supported_cpuid(kvm_state, wi->cpuid_eax,
wi->cpuid_ecx,
wi->cpuid_reg);
+ if (allow_emulation) {
+ r |= kvm_arch_get_emulated_cpuid(kvm_state, wi->cpuid_eax,
+ wi->cpuid_ecx,
+ wi->cpuid_reg);
+ }
} else if (tcg_enabled()) {
r = wi->tcg_features;
} else {
@@ -1920,7 +1928,8 @@ static int x86_cpu_filter_features(X86CPU *cpu)
for (w = 0; w < FEATURE_WORDS; w++) {
uint32_t host_feat =
- x86_cpu_get_supported_feature_word(w, cpu->migratable);
+ x86_cpu_get_supported_feature_word(w, cpu->migratable,
+ cpu->allow_emulation);
uint32_t requested_features = env->features[w];
env->features[w] &= host_feat;
cpu->filtered_features[w] = requested_features & ~env->features[w];
@@ -2854,6 +2863,7 @@ static Property x86_cpu_properties[] = {
DEFINE_PROP_BOOL("hv-time", X86CPU, hyperv_time, false),
DEFINE_PROP_BOOL("check", X86CPU, check_cpuid, false),
DEFINE_PROP_BOOL("enforce", X86CPU, enforce_cpuid, false),
+ DEFINE_PROP_BOOL("x-allow-emulation", X86CPU, allow_emulation, true),
DEFINE_PROP_END_OF_LIST()
};
--
1.9.0
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
