Re: [Qemu-devel] [PATCH v3 1/1] cpu: report hyperv feature words through qom

["Denis V. Lunev" <den@openvz.org>]

On 06/24/2016 01:49 PM, Denis V. Lunev wrote:
> From: Evgeny Yakovlev <eyakovlev@virtuozzo.com>
>
> This change adds hyperv feature words report through qom rpc.
>
> When VM is configured with hyperv features enabled
> libvirt will check that required feature words are set
> in cpuid leaf 40000003 through qom request.
>
> Currently qemu does not report hyperv feature words
> which prevents windows guests from starting with libvirt.
>
> To avoid conflicting with current hyperv properties all added feature
> words cannot be set directly with -cpu +feature yet.
>
> Signed-off-by: Evgeny Yakovlev <eyakovlev@virtuozzo.com>
> Signed-off-by: Denis V. Lunev <den@openvz.org>
> CC: Paolo Bonzini <pbonzini@redhat.com>
> CC: Richard Henderson <rth@twiddle.net>
> CC: Eduardo Habkost <ehabkost@redhat.com>
> CC: Marcelo Tosatti <mtosatti@redhat.com>
> ---
> Changes from v2:
> - removed all hyperv feature_names so that we don't have two ways of
>    setting CPUID bits
>
> Changes from v1:
> - renamed hyperv features so they don't conflict with hyperv properties
> - refactored kvm_arch_init_vcpu to process hyperv props into feature words
>
> target-i386/cpu.c |  53 +++++++++++++++++++++++++
>   target-i386/cpu.h |   3 ++
>   target-i386/kvm.c | 114 +++++++++++++++++++++++++++++++-----------------------
>   3 files changed, 122 insertions(+), 48 deletions(-)
>
> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
> index 3bd3cfc..d07da78 100644
> --- a/target-i386/cpu.c
> +++ b/target-i386/cpu.c
> @@ -245,6 +245,47 @@ static const char *kvm_feature_name[] = {
>       NULL, NULL, NULL, NULL,
>   };
>   
> +static const char *hyperv_priv_feature_name[] = {
> +    NULL /* hv_msr_vp_runtime_access */, NULL /* hv_msr_time_refcount_access */,
> +    NULL /* hv_msr_synic_access */, NULL /* hv_msr_stimer_access */,
> +    NULL /* hv_msr_apic_access */, NULL /* hv_msr_hypercall_access */,
> +    NULL /* hv_vpindex_access */, NULL /* hv_msr_reset_access */,
> +    NULL /* hv_msr_stats_access */, NULL /* hv_reftsc_access */,
> +    NULL /* hv_msr_idle_access */, NULL /* hv_msr_frequency_access */,
> +    NULL, NULL, NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +};
> +
> +static const char *hyperv_ident_feature_name[] = {
> +    NULL /* hv_create_partitions */, NULL /* hv_access_partition_id */,
> +    NULL /* hv_access_memory_pool */, NULL /* hv_adjust_message_buffers */,
> +    NULL /* hv_post_messages */, NULL /* hv_signal_events */,
> +    NULL /* hv_create_port */, NULL /* hv_connect_port */,
> +    NULL /* hv_access_stats */, NULL, NULL, NULL /* hv_debugging */,
> +    NULL /* hv_cpu_power_management */, NULL /* hv_configure_profiler */,
> +    NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +};
> +
> +static const char *hyperv_misc_feature_name[] = {
> +    NULL /* hv_mwait */, NULL /* hv_guest_debugging */,
> +    NULL /* hv_perf_monitor */, NULL /* hv_cpu_dynamic_part */,
> +    NULL /* hv_hypercall_params_xmm */, NULL /* hv_guest_idle_state */,
> +    NULL, NULL,
> +    NULL, NULL, NULL /* hv_guest_crash_msr */, NULL,
> +    NULL, NULL, NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +    NULL, NULL, NULL, NULL,
> +};
> +
>   static const char *svm_feature_name[] = {
>       "npt", "lbrv", "svm_lock", "nrip_save",
>       "tsc_scale", "vmcb_clean",  "flushbyasid", "decodeassists",
> @@ -411,6 +452,18 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
>           .cpuid_eax = KVM_CPUID_FEATURES, .cpuid_reg = R_EAX,
>           .tcg_features = TCG_KVM_FEATURES,
>       },
> +    [FEAT_HYPERV_EAX] = {
> +        .feat_names = hyperv_priv_feature_name,
> +        .cpuid_eax = 0x40000003, .cpuid_reg = R_EAX,
> +    },
> +    [FEAT_HYPERV_EBX] = {
> +        .feat_names = hyperv_ident_feature_name,
> +        .cpuid_eax = 0x40000003, .cpuid_reg = R_EBX,
> +    },
> +    [FEAT_HYPERV_EDX] = {
> +        .feat_names = hyperv_misc_feature_name,
> +        .cpuid_eax = 0x40000003, .cpuid_reg = R_EDX,
> +    },
>       [FEAT_SVM] = {
>           .feat_names = svm_feature_name,
>           .cpuid_eax = 0x8000000A, .cpuid_reg = R_EDX,
> diff --git a/target-i386/cpu.h b/target-i386/cpu.h
> index d9ab884..4496c8b 100644
> --- a/target-i386/cpu.h
> +++ b/target-i386/cpu.h
> @@ -440,6 +440,9 @@ typedef enum FeatureWord {
>       FEAT_8000_0007_EDX, /* CPUID[8000_0007].EDX */
>       FEAT_C000_0001_EDX, /* CPUID[C000_0001].EDX */
>       FEAT_KVM,           /* CPUID[4000_0001].EAX (KVM_CPUID_FEATURES) */
> +    FEAT_HYPERV_EAX,    /* CPUID[4000_0003].EAX */
> +    FEAT_HYPERV_EBX,    /* CPUID[4000_0003].EBX */
> +    FEAT_HYPERV_EDX,    /* CPUID[4000_0003].EDX */
>       FEAT_SVM,           /* CPUID[8000_000A].EDX */
>       FEAT_XSAVE,         /* CPUID[EAX=0xd,ECX=1].EAX */
>       FEAT_6_EAX,         /* CPUID[6].EAX */
> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> index f3698f1..f44e3c7 100644
> --- a/target-i386/kvm.c
> +++ b/target-i386/kvm.c
> @@ -574,6 +574,66 @@ static int kvm_arch_set_tsc_khz(CPUState *cs)
>       return 0;
>   }
>   
> +static int hyperv_handle_properties(CPUState *cs)
> +{
> +    X86CPU *cpu = X86_CPU(cs);
> +    CPUX86State *env = &cpu->env;
> +
> +    if (cpu->hyperv_relaxed_timing) {
> +        env->features[FEAT_HYPERV_EAX] |= HV_X64_MSR_HYPERCALL_AVAILABLE;
> +    }
> +    if (cpu->hyperv_vapic) {
> +        env->features[FEAT_HYPERV_EAX] |= HV_X64_MSR_HYPERCALL_AVAILABLE;
> +        env->features[FEAT_HYPERV_EAX] |= HV_X64_MSR_APIC_ACCESS_AVAILABLE;
> +        has_msr_hv_vapic = true;
> +    }
> +    if (cpu->hyperv_time &&
> +            kvm_check_extension(cs->kvm_state, KVM_CAP_HYPERV_TIME) > 0) {
> +        env->features[FEAT_HYPERV_EAX] |= HV_X64_MSR_HYPERCALL_AVAILABLE;
> +        env->features[FEAT_HYPERV_EAX] |= HV_X64_MSR_TIME_REF_COUNT_AVAILABLE;
> +        env->features[FEAT_HYPERV_EAX] |= 0x200;
> +        has_msr_hv_tsc = true;
> +    }
> +    if (cpu->hyperv_crash && has_msr_hv_crash) {
> +        env->features[FEAT_HYPERV_EDX] |= HV_X64_GUEST_CRASH_MSR_AVAILABLE;
> +    }
> +    if (cpu->hyperv_reset && has_msr_hv_reset) {
> +        env->features[FEAT_HYPERV_EAX] |= HV_X64_MSR_RESET_AVAILABLE;
> +    }
> +    if (cpu->hyperv_vpindex && has_msr_hv_vpindex) {
> +        env->features[FEAT_HYPERV_EAX] |= HV_X64_MSR_VP_INDEX_AVAILABLE;
> +    }
> +    if (cpu->hyperv_runtime && has_msr_hv_runtime) {
> +        env->features[FEAT_HYPERV_EAX] |= HV_X64_MSR_VP_RUNTIME_AVAILABLE;
> +    }
> +    if (cpu->hyperv_synic) {
> +        int sint;
> +
> +        if (!has_msr_hv_synic ||
> +            kvm_vcpu_enable_cap(cs, KVM_CAP_HYPERV_SYNIC, 0)) {
> +            fprintf(stderr, "Hyper-V SynIC is not supported by kernel\n");
> +            return -ENOSYS;
> +        }
> +
> +        env->features[FEAT_HYPERV_EAX] |= HV_X64_MSR_SYNIC_AVAILABLE;
> +        env->msr_hv_synic_version = HV_SYNIC_VERSION_1;
> +        for (sint = 0; sint < ARRAY_SIZE(env->msr_hv_synic_sint); sint++) {
> +            env->msr_hv_synic_sint[sint] = HV_SYNIC_SINT_MASKED;
> +        }
> +    }
> +    if (cpu->hyperv_stimer) {
> +        if (!has_msr_hv_stimer) {
> +            fprintf(stderr, "Hyper-V timers aren't supported by kernel\n");
> +            return -ENOSYS;
> +        }
> +        env->features[FEAT_HYPERV_EAX] |= HV_X64_MSR_SYNTIMER_AVAILABLE;
> +    }
> +    if (MACHINE_GET_CLASS(current_machine)->hot_add_cpu != NULL) {
> +        env->features[FEAT_HYPERV_EDX] |= HV_X64_CPU_DYNAMIC_PARTITIONING_AVAILABLE;
> +    }
> +    return 0;
> +}
> +
>   static Error *invtsc_mig_blocker;
>   
>   #define KVM_MAX_CPUID_ENTRIES  100
> @@ -633,56 +693,14 @@ int kvm_arch_init_vcpu(CPUState *cs)
>   
>           c = &cpuid_data.entries[cpuid_i++];
>           c->function = HYPERV_CPUID_FEATURES;
> -        if (cpu->hyperv_relaxed_timing) {
> -            c->eax |= HV_X64_MSR_HYPERCALL_AVAILABLE;
> -        }
> -        if (cpu->hyperv_vapic) {
> -            c->eax |= HV_X64_MSR_HYPERCALL_AVAILABLE;
> -            c->eax |= HV_X64_MSR_APIC_ACCESS_AVAILABLE;
> -            has_msr_hv_vapic = true;
> -        }
> -        if (cpu->hyperv_time &&
> -            kvm_check_extension(cs->kvm_state, KVM_CAP_HYPERV_TIME) > 0) {
> -            c->eax |= HV_X64_MSR_HYPERCALL_AVAILABLE;
> -            c->eax |= HV_X64_MSR_TIME_REF_COUNT_AVAILABLE;
> -            c->eax |= 0x200;
> -            has_msr_hv_tsc = true;
> -        }
> -        if (cpu->hyperv_crash && has_msr_hv_crash) {
> -            c->edx |= HV_X64_GUEST_CRASH_MSR_AVAILABLE;
> -        }
> -        c->edx |= HV_X64_CPU_DYNAMIC_PARTITIONING_AVAILABLE;
> -        if (cpu->hyperv_reset && has_msr_hv_reset) {
> -            c->eax |= HV_X64_MSR_RESET_AVAILABLE;
> -        }
> -        if (cpu->hyperv_vpindex && has_msr_hv_vpindex) {
> -            c->eax |= HV_X64_MSR_VP_INDEX_AVAILABLE;
> -        }
> -        if (cpu->hyperv_runtime && has_msr_hv_runtime) {
> -            c->eax |= HV_X64_MSR_VP_RUNTIME_AVAILABLE;
> +        r = hyperv_handle_properties(cs);
> +        if (r) {
> +            return r;
>           }
> -        if (cpu->hyperv_synic) {
> -            int sint;
> -
> -            if (!has_msr_hv_synic ||
> -                kvm_vcpu_enable_cap(cs, KVM_CAP_HYPERV_SYNIC, 0)) {
> -                fprintf(stderr, "Hyper-V SynIC is not supported by kernel\n");
> -                return -ENOSYS;
> -            }
> +        c->eax = env->features[FEAT_HYPERV_EAX];
> +        c->ebx = env->features[FEAT_HYPERV_EBX];
> +        c->edx = env->features[FEAT_HYPERV_EDX];
>   
> -            c->eax |= HV_X64_MSR_SYNIC_AVAILABLE;
> -            env->msr_hv_synic_version = HV_SYNIC_VERSION_1;
> -            for (sint = 0; sint < ARRAY_SIZE(env->msr_hv_synic_sint); sint++) {
> -                env->msr_hv_synic_sint[sint] = HV_SYNIC_SINT_MASKED;
> -            }
> -        }
> -        if (cpu->hyperv_stimer) {
> -            if (!has_msr_hv_stimer) {
> -                fprintf(stderr, "Hyper-V timers aren't supported by kernel\n");
> -                return -ENOSYS;
> -            }
> -            c->eax |= HV_X64_MSR_SYNTIMER_AVAILABLE;
> -        }
>           c = &cpuid_data.entries[cpuid_i++];
>           c->function = HYPERV_CPUID_ENLIGHTMENT_INFO;
>           if (cpu->hyperv_relaxed_timing) {
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