On 05.07.2017 10:49, Greg Kurz wrote:
> When running KVM on POWER, we allow the user to pass "-cpu POWERx" instead
> of "-cpu host". This is achieved by patching the ppc_cpu_aliases[] array
> so that "POWERx" points to the CPU class with the same PVR as the host CPU.
> This causes CPUs to be instantiated from this CPU class instead of the
> TYPE_HOST_POWERPC_CPU class which is used with "-cpu host". These CPUs thus
> miss all the KVM specific tuning from kvmppc_host_cpu_class_init().
>
> This currently causes QEMU with "-cpu POWER9" to fail when running KVM on a
> POWER9 DD1 host:
>
> qemu-system-ppc64: Register sync failed... If you're using kvm-hv.ko, only
> "-cpu host" is possible
> kvm_init_vcpu failed: Invalid argument
>
> Let's have the "POWERx" alias to point to TYPE_HOST_POWERPC_CPU directly,
> so that "-cpu POWERx" instantiates CPUs from the same class as "-cpu host".
>
> Signed-off-by: Greg Kurz <gr...@kaod.org>
> ---
> target/ppc/kvm.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
> index f2f7c531bc7b..f7a7ea5858a3 100644
> --- a/target/ppc/kvm.c
> +++ b/target/ppc/kvm.c
> @@ -2445,6 +2445,7 @@ static int kvm_ppc_register_host_cpu_type(void)
> .class_init = kvmppc_host_cpu_class_init,
> };
> PowerPCCPUClass *pvr_pcc;
> + ObjectClass *oc;
> DeviceClass *dc;
> int i;
>
> @@ -2455,6 +2456,9 @@ static int kvm_ppc_register_host_cpu_type(void)
> type_info.parent = object_class_get_name(OBJECT_CLASS(pvr_pcc));
> type_register(&type_info);
>
> + oc = object_class_by_name(type_info.name);
> + g_assert(oc);
> +
> #if defined(TARGET_PPC64)
> type_info.name = g_strdup_printf("%s-"TYPE_SPAPR_CPU_CORE, "host");
> type_info.parent = TYPE_SPAPR_CPU_CORE,
> @@ -2474,7 +2478,6 @@ static int kvm_ppc_register_host_cpu_type(void)
> dc = DEVICE_CLASS(ppc_cpu_get_family_class(pvr_pcc));
> for (i = 0; ppc_cpu_aliases[i].alias != NULL; i++) {
> if (strcmp(ppc_cpu_aliases[i].alias, dc->desc) == 0) {
> - ObjectClass *oc = OBJECT_CLASS(pvr_pcc);
> char *suffix;
>
> ppc_cpu_aliases[i].model = g_strdup(object_class_get_name(oc));
>
Yes, I think that should be fine, too.
Reviewed-by: Thomas Huth <th...@redhat.com>
