Re: [PATCH RESEND] i386/kvm: support guest access CORE cstate

From: Paolo Bonzini
Date: Mon Jul 15 2019 - 05:17:03 EST


On 15/07/19 03:28, Wanpeng Li wrote:
> From: Wanpeng Li <wanpengli@xxxxxxxxxxx>
>
> Allow guest reads CORE cstate when exposing host CPU power management capabilities
> to the guest. PKG cstate is restricted to avoid a guest to get the whole package
> information in multi-tenant scenario.
>
> Cc: Eduardo Habkost <ehabkost@xxxxxxxxxx>
> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Cc: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
> Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>

Hi,

QEMU is in hard freeze now. This will be applied after the release.

Thanks,

Paolo

> ---
> linux-headers/linux/kvm.h | 4 +++-
> target/i386/kvm.c | 3 ++-
> 2 files changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
> index b53ee59..d648fde 100644
> --- a/linux-headers/linux/kvm.h
> +++ b/linux-headers/linux/kvm.h
> @@ -696,9 +696,11 @@ struct kvm_ioeventfd {
> #define KVM_X86_DISABLE_EXITS_MWAIT (1 << 0)
> #define KVM_X86_DISABLE_EXITS_HLT (1 << 1)
> #define KVM_X86_DISABLE_EXITS_PAUSE (1 << 2)
> +#define KVM_X86_DISABLE_EXITS_CSTATE (1 << 3)
> #define KVM_X86_DISABLE_VALID_EXITS (KVM_X86_DISABLE_EXITS_MWAIT | \
> KVM_X86_DISABLE_EXITS_HLT | \
> - KVM_X86_DISABLE_EXITS_PAUSE)
> + KVM_X86_DISABLE_EXITS_PAUSE | \
> + KVM_X86_DISABLE_EXITS_CSTATE)
>
> /* for KVM_ENABLE_CAP */
> struct kvm_enable_cap {
> diff --git a/target/i386/kvm.c b/target/i386/kvm.c
> index 3b29ce5..49a0cc1 100644
> --- a/target/i386/kvm.c
> +++ b/target/i386/kvm.c
> @@ -1645,7 +1645,8 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
> if (disable_exits) {
> disable_exits &= (KVM_X86_DISABLE_EXITS_MWAIT |
> KVM_X86_DISABLE_EXITS_HLT |
> - KVM_X86_DISABLE_EXITS_PAUSE);
> + KVM_X86_DISABLE_EXITS_PAUSE |
> + KVM_X86_DISABLE_EXITS_CSTATE);
> }
>
> ret = kvm_vm_enable_cap(s, KVM_CAP_X86_DISABLE_EXITS, 0,
>