@@ -632,11 +632,6 @@ static int hyperv_handle_properties(CPUState *cs)
X86CPU *cpu = X86_CPU(cs);
CPUX86State *env = &cpu->env;
- if (cpu->hyperv_time &&
- kvm_check_extension(cs->kvm_state, KVM_CAP_HYPERV_TIME) <= 0) {
- cpu->hyperv_time = false;
- }
-
if (cpu->hyperv_relaxed_timing) {
env->features[FEAT_HYPERV_EAX] |= HV_HYPERCALL_AVAILABLE;
}
@@ -645,6 +640,12 @@ static int hyperv_handle_properties(CPUState *cs)
env->features[FEAT_HYPERV_EAX] |= HV_APIC_ACCESS_AVAILABLE;
}
if (cpu->hyperv_time) {
+ if (kvm_check_extension(cs->kvm_state, KVM_CAP_HYPERV_TIME) <= 0) {
+ fprintf(stderr, "Hyper-V clocksources "
+ "(requested by 'hv-time' cpu flag) "
+ "are not supported by kernel\n");
+ return -ENOSYS;
+ }
env->features[FEAT_HYPERV_EAX] |= HV_HYPERCALL_AVAILABLE;
env->features[FEAT_HYPERV_EAX] |= HV_TIME_REF_COUNT_AVAILABLE;
env->features[FEAT_HYPERV_EAX] |= HV_REFERENCE_TSC_AVAILABLE;
@@ -659,17 +660,41 @@ static int hyperv_handle_properties(CPUState *cs)
env->features[FEAT_HYPERV_EAX] |= HV_ACCESS_FREQUENCY_MSRS;
env->features[FEAT_HYPERV_EDX] |= HV_FREQUENCY_MSRS_AVAILABLE;
}
- if (cpu->hyperv_crash && has_msr_hv_crash) {
+ if (cpu->hyperv_crash) {
+ if (!has_msr_hv_crash) {
+ fprintf(stderr, "Hyper-V crash MSRs "
+ "(requested by 'hv-crash' cpu flag) "
+ "are not supported by kernel\n");
+ return -ENOSYS;
+ }
env->features[FEAT_HYPERV_EDX] |= HV_GUEST_CRASH_MSR_AVAILABLE;
}
env->features[FEAT_HYPERV_EDX] |= HV_CPU_DYNAMIC_PARTITIONING_AVAILABLE;
- if (cpu->hyperv_reset && has_msr_hv_reset) {
+ if (cpu->hyperv_reset) {
+ if (!has_msr_hv_reset) {
+ fprintf(stderr, "Hyper-V reset MSR "
+ "(requested by 'hv-reset' cpu flag) "
+ "is not supported by kernel\n");
+ return -ENOSYS;
+ }
env->features[FEAT_HYPERV_EAX] |= HV_RESET_AVAILABLE;
}
- if (cpu->hyperv_vpindex && has_msr_hv_vpindex) {
+ if (cpu->hyperv_vpindex) {
+ if (!has_msr_hv_vpindex) {
+ fprintf(stderr, "Hyper-V VP_INDEX MSR "
+ "(requested by 'hv-vpindex' cpu flag) "
+ "is not supported by kernel\n");
+ return -ENOSYS;
+ }
env->features[FEAT_HYPERV_EAX] |= HV_VP_INDEX_AVAILABLE;
}
- if (cpu->hyperv_runtime && has_msr_hv_runtime) {
+ if (cpu->hyperv_runtime) {
+ if (!has_msr_hv_runtime) {
+ fprintf(stderr, "Hyper-V VP_RUNTIME MSR "
+ "(requested by 'hv-runtime' cpu flag) "
+ "is not supported by kernel\n");
+ return -ENOSYS;
+ }
env->features[FEAT_HYPERV_EAX] |= HV_VP_RUNTIME_AVAILABLE;
}
if (cpu->hyperv_synic) {
In order to guarantee compatibility on migration, QEMU should have complete control over the features it announces to the guest via CPUID. However, for a number of Hyper-V-related cpu properties, if the corresponding feature is not supported by the underlying KVM, the propery is silently ignored and the feature is not announced to the guest. Refuse to start with an error instead. Signed-off-by: Roman Kagan <rkagan@virtuozzo.com> --- v2 -> v3: - include the fix for 'hv-time' missed previously v1 -> v2: - indicate what flag requested the feature that can't be enabled in the error message - fix a typo in the error message for VP_RUNTIME target/i386/kvm.c | 43 ++++++++++++++++++++++++++++++++++--------- 1 file changed, 34 insertions(+), 9 deletions(-)