Re: [PATCH RFC 05/22] i386: move hyperv_version_id initialization to x86_cpu_realizefn()

[Eduardo Habkost <ehabkost@redhat.com>]

On Fri, Sep 04, 2020 at 04:54:14PM +0200, Vitaly Kuznetsov wrote:
> As a preparation to expanding Hyper-V CPU features early, move
> hyperv_version_id initialization to x86_cpu_realizefn().
> 
> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
> ---
>  target/i386/cpu.c |  4 ++++
>  target/i386/cpu.h |  1 +
>  target/i386/kvm.c | 14 ++++++++++++--
>  3 files changed, 17 insertions(+), 2 deletions(-)
> 
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 16888125a30a..e605399eb8c0 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -6644,6 +6644,10 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
>      cpu->hyperv_interface_id[2] = 0;
>      cpu->hyperv_interface_id[3] = 0;
>  
> +    /* Hypervisor system identity */
> +    cpu->hyperv_version_id[0] = 0x00001bbc;
> +    cpu->hyperv_version_id[1] = 0x00060001;
> +
>      if (cpu->ucode_rev == 0) {
>          /* The default is the same as KVM's.  */
>          if (IS_AMD_CPU(env)) {
> diff --git a/target/i386/cpu.h b/target/i386/cpu.h
> index 91edc54a268c..2630ffd2d4b2 100644
> --- a/target/i386/cpu.h
> +++ b/target/i386/cpu.h
> @@ -1661,6 +1661,7 @@ struct X86CPU {
>      OnOffAuto hyperv_no_nonarch_cs;
>      uint32_t hyperv_vendor_id[3];
>      uint32_t hyperv_interface_id[4];
> +    uint32_t hyperv_version_id[4];
>  
>      bool check_cpuid;
>      bool enforce_cpuid;
> diff --git a/target/i386/kvm.c b/target/i386/kvm.c
> index a36c65100cd0..169bae2779a4 100644
> --- a/target/i386/kvm.c
> +++ b/target/i386/kvm.c
> @@ -1239,6 +1239,14 @@ static int hyperv_handle_properties(CPUState *cs,
>              cpu->hyperv_interface_id[3] = c->edx;
>          }
>  
> +        c = cpuid_find_entry(cpuid, HV_CPUID_VERSION, 0);
> +        if (c) {
> +            cpu->hyperv_version_id[0] = c->eax;
> +            cpu->hyperv_version_id[1] = c->ebx;
> +            cpu->hyperv_version_id[2] = c->ecx;
> +            cpu->hyperv_version_id[3] = c->edx;
> +        }
> +

Same questions I had for vendor id: is hyperv_version_id broken
when using hv-passthrough today?  Should this go to a separate
patch?

>          c = cpuid_find_entry(cpuid, HV_CPUID_FEATURES, 0);
>          if (c) {
>              env->features[FEAT_HYPERV_EAX] = c->eax;
> @@ -1328,8 +1336,10 @@ static int hyperv_handle_properties(CPUState *cs,
>  
>      c = &cpuid_ent[cpuid_i++];
>      c->function = HV_CPUID_VERSION;
> -    c->eax = 0x00001bbc;
> -    c->ebx = 0x00060001;
> +    c->eax = cpu->hyperv_version_id[0];
> +    c->ebx = cpu->hyperv_version_id[1];
> +    c->ecx = cpu->hyperv_version_id[2];
> +    c->edx = cpu->hyperv_version_id[3];
>  
>      c = &cpuid_ent[cpuid_i++];
>      c->function = HV_CPUID_FEATURES;
> -- 
> 2.25.4
> 

-- 
Eduardo