[Qemu-devel] [PATCH] i386: fix '-cpu ?' output for host cpu type

[Qemu-devel] [PATCH] i386: fix '-cpu ?' output for host cpu type

[Greg Kurz]

Since commit d6dcc5583e7, '-cpu ?' shows the description of the
X86_CPU_TYPE_NAME("max") for the host CPU model:

Enables all features supported by the accelerator in the current host

instead of the expected:

KVM processor with all supported host features

or

HVF processor with all supported host features

This is caused by the early use of kvm_enabled() and hvf_enabled() in
a class_init function. Since the accelerator isn't configured yet, both
helpers return false unconditionally.

A QEMU binary will only be compiled with one of these accelerators, not
both. The appropriate description can thus be decided at build time.

Signed-off-by: Greg Kurz <groug@kaod.org>
---
 target/i386/cpu.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 1e6a7d0a7504..e5da60b28973 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -2838,13 +2838,13 @@ static void host_x86_cpu_class_init(ObjectClass *oc, void *data)
     xcc->host_cpuid_required = true;
     xcc->ordering = 8;
 
-    if (kvm_enabled()) {
-        xcc->model_description =
-            "KVM processor with all supported host features ";
-    } else if (hvf_enabled()) {
-        xcc->model_description =
-            "HVF processor with all supported host features ";
-    }
+#if defined(CONFIG_KVM)
+    xcc->model_description =
+        "KVM processor with all supported host features ";
+#elif defined(CONFIG_HVF)
+    xcc->model_description =
+        "HVF processor with all supported host features ";
+#endif
 }
 
 static const TypeInfo host_x86_cpu_type_info = {

Re: [Qemu-devel] [PATCH] i386: fix '-cpu ?' output for host cpu type

[Daniel P. Berrangé]

On Mon, Jul 02, 2018 at 06:56:06PM +0200, Greg Kurz wrote:
> Since commit d6dcc5583e7, '-cpu ?' shows the description of the
> X86_CPU_TYPE_NAME("max") for the host CPU model:
> 
> Enables all features supported by the accelerator in the current host
> 
> instead of the expected:
> 
> KVM processor with all supported host features
> 
> or
> 
> HVF processor with all supported host features
> 
> This is caused by the early use of kvm_enabled() and hvf_enabled() in
> a class_init function. Since the accelerator isn't configured yet, both
> helpers return false unconditionally.
> 
> A QEMU binary will only be compiled with one of these accelerators, not
> both. The appropriate description can thus be decided at build time.
> 
> Signed-off-by: Greg Kurz <groug@kaod.org>
> ---
>  target/i386/cpu.c |   14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 1e6a7d0a7504..e5da60b28973 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -2838,13 +2838,13 @@ static void host_x86_cpu_class_init(ObjectClass *oc, void *data)

Sigh, yet another case of relying on runtime state during class_init impls.

>      xcc->host_cpuid_required = true;
>      xcc->ordering = 8;
>  
> -    if (kvm_enabled()) {
> -        xcc->model_description =
> -            "KVM processor with all supported host features ";
> -    } else if (hvf_enabled()) {
> -        xcc->model_description =
> -            "HVF processor with all supported host features ";
> -    }
> +#if defined(CONFIG_KVM)
> +    xcc->model_description =
> +        "KVM processor with all supported host features ";
> +#elif defined(CONFIG_HVF)
> +    xcc->model_description =
> +        "HVF processor with all supported host features ";
> +#endif
>  }
>  
>  static const TypeInfo host_x86_cpu_type_info = {

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>


Regards,
Daniel
-- 
|: https://berrange.com      -o-    https://www.flickr.com/photos/dberrange :|
|: https://libvirt.org         -o-            https://fstop138.berrange.com :|
|: https://entangle-photo.org    -o-    https://www.instagram.com/dberrange :|

Re: [Qemu-devel] [PATCH] i386: fix '-cpu ?' output for host cpu type

[Paolo Bonzini]

On 02/07/2018 18:56, Greg Kurz wrote:
> Since commit d6dcc5583e7, '-cpu ?' shows the description of the
> X86_CPU_TYPE_NAME("max") for the host CPU model:
> 
> Enables all features supported by the accelerator in the current host
> 
> instead of the expected:
> 
> KVM processor with all supported host features
> 
> or
> 
> HVF processor with all supported host features
> 
> This is caused by the early use of kvm_enabled() and hvf_enabled() in
> a class_init function. Since the accelerator isn't configured yet, both
> helpers return false unconditionally.
> 
> A QEMU binary will only be compiled with one of these accelerators, not
> both. The appropriate description can thus be decided at build time.
> 
> Signed-off-by: Greg Kurz <groug@kaod.org>
> ---
>  target/i386/cpu.c |   14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 1e6a7d0a7504..e5da60b28973 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -2838,13 +2838,13 @@ static void host_x86_cpu_class_init(ObjectClass *oc, void *data)
>      xcc->host_cpuid_required = true;
>      xcc->ordering = 8;
>  
> -    if (kvm_enabled()) {
> -        xcc->model_description =
> -            "KVM processor with all supported host features ";
> -    } else if (hvf_enabled()) {
> -        xcc->model_description =
> -            "HVF processor with all supported host features ";
> -    }
> +#if defined(CONFIG_KVM)
> +    xcc->model_description =
> +        "KVM processor with all supported host features ";
> +#elif defined(CONFIG_HVF)
> +    xcc->model_description =
> +        "HVF processor with all supported host features ";
> +#endif
>  }
>  
>  static const TypeInfo host_x86_cpu_type_info = {
> 

Queued, thanks.

Paolo

Re: [Qemu-devel] [PATCH] i386: fix '-cpu ?' output for host cpu type

[Eric Blake]

On 07/02/2018 11:56 AM, Greg Kurz wrote:
> Since commit d6dcc5583e7, '-cpu ?' shows the description of the
> X86_CPU_TYPE_NAME("max") for the host CPU model:

In the subject line and here, let's favor '-cpu help' as the preferred 
spelling for this command line option.  (-cpu ? requires shell quoting 
to avoid unintentionally globbing to one-letter files in the current 
directory)

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org