Re: [Qemu-devel] [PATCH 1/1] hyperv: cpu hotplug fix with HyperV enabled

["Andreas Färber" <afaerber@suse.de>]

Am 11.02.2016 um 21:19 schrieb Denis V. Lunev:
> From: "Alexey V. Kostyushko" <aleksko@virtuozzo.com>
> 
> With Hyper-V enabled CPU hotplug stops working. The CPU appears in device
> manager on Windows but does not appear in peformance monitor and control
> panel.
> 
> The root of the problem is the following. Windows checks
> HV_X64_CPU_DYNAMIC_PARTITIONING_AVAILABLE bit in CPUID. The presence of
> this bit is enough to cure the situation.
> 
> Add option 'hv-cpuhotplug' to control this behavior.
> 
> Signed-off-by: Alexey V. Kostyushko <aleksko@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: "Andreas Färber" <afaerber@suse.de>
> ---
>  target-i386/cpu-qom.h | 1 +
>  target-i386/cpu.c     | 1 +
>  target-i386/kvm.c     | 6 +++++-
>  3 files changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/target-i386/cpu-qom.h b/target-i386/cpu-qom.h
> index 5f9d960..4aec616 100644
> --- a/target-i386/cpu-qom.h
> +++ b/target-i386/cpu-qom.h
> @@ -96,6 +96,7 @@ typedef struct X86CPU {
>      bool hyperv_runtime;
>      bool hyperv_synic;
>      bool hyperv_stimer;
> +    bool hyperv_cpuhotplug;
>      bool check_cpuid;
>      bool enforce_cpuid;
>      bool expose_kvm;
> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
> index b255644..32c38ae 100644
> --- a/target-i386/cpu.c
> +++ b/target-i386/cpu.c
> @@ -3172,6 +3172,7 @@ static Property x86_cpu_properties[] = {
>      DEFINE_PROP_BOOL("hv-runtime", X86CPU, hyperv_runtime, false),
>      DEFINE_PROP_BOOL("hv-synic", X86CPU, hyperv_synic, false),
>      DEFINE_PROP_BOOL("hv-stimer", X86CPU, hyperv_stimer, false),
> +    DEFINE_PROP_BOOL("hv-cpuhotplug", X86CPU, hyperv_cpuhotplug, false),

Is "cpuhotplug" some fixed HyperV name? Otherwise we generally use a
dashes convention for QOM properties, i.e. "hv-cpu-hotplug".

Regards,
Andreas

>      DEFINE_PROP_BOOL("check", X86CPU, check_cpuid, true),
>      DEFINE_PROP_BOOL("enforce", X86CPU, enforce_cpuid, false),
>      DEFINE_PROP_BOOL("kvm", X86CPU, expose_kvm, true),
[snip]

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