Re: [PATCH 1/2] KVM: nVMX: Clean up and fix pin-based execution controls

Gleb Natapov
2013-03-13T14:21:43Z

On Wed, Mar 13, 2013 at 11:30:50AM +0100, Jan Kiszka wrote:
> Only interrupt and NMI exiting are mandatory for KVM to work, thus can
> be exposed to the guest unconditionally, virtual NMI exiting is
> optional. So we must not advertise it unless the host supports it.
>
> Introduce the symbolic constant PIN_BASED_ALWAYSON_WITHOUT_TRUE_MSR at
> this chance.
>
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Applied, thanks.

> ---
> arch/x86/include/asm/vmx.h | 2 ++
> arch/x86/kvm/vmx.c | 10 ++++++----
> 2 files changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
> index e1cc048c..056bda5 100644
> --- a/arch/x86/include/asm/vmx.h
> +++ b/arch/x86/include/asm/vmx.h
> @@ -71,6 +71,8 @@
> #define PIN_BASED_NMI_EXITING 0x00000008
> #define PIN_BASED_VIRTUAL_NMIS 0x00000020
>
> +#define PIN_BASED_ALWAYSON_WITHOUT_TRUE_MSR 0x00000016
> +
> #define VM_EXIT_SAVE_DEBUG_CONTROLS 0x00000002
> #define VM_EXIT_HOST_ADDR_SPACE_SIZE 0x00000200
> #define VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL 0x00001000
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index f310bcf..0f0cc6a 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -2041,14 +2041,16 @@ static __init void nested_vmx_setup_ctls_msrs(void)
> */
>
> /* pin-based controls */
> + rdmsr(MSR_IA32_VMX_PINBASED_CTLS,
> + nested_vmx_pinbased_ctls_low, nested_vmx_pinbased_ctls_high);
> /*
> * According to the Intel spec, if bit 55 of VMX_BASIC is off (as it is
> * in our case), bits 1, 2 and 4 (i.e., 0x16) must be 1 in this MSR.
> */
> - nested_vmx_pinbased_ctls_low = 0x16 ;
> - nested_vmx_pinbased_ctls_high = 0x16 |
> - PIN_BASED_EXT_INTR_MASK | PIN_BASED_NMI_EXITING |
> - PIN_BASED_VIRTUAL_NMIS;
> + nested_vmx_pinbased_ctls_low |= PIN_BASED_ALWAYSON_WITHOUT_TRUE_MSR;
> + nested_vmx_pinbased_ctls_high &= PIN_BASED_EXT_INTR_MASK |
> + PIN_BASED_NMI_EXITING | PIN_BASED_VIRTUAL_NMIS;
> + nested_vmx_pinbased_ctls_high |= PIN_BASED_ALWAYSON_WITHOUT_TRUE_MSR;
>
> /*
> * Exit controls
> --
> 1.7.3.4

--
Gleb.