Re: [PATCH v3 3/4] KVM: nVMX: Track whether changes in L0 require MSR bitmap for L2 to be rebuilt

Sean Christopherson
2021-11-05T01:05:58Z

On Wed, Oct 13, 2021, Vitaly Kuznetsov wrote:
> diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
> index 592217fd7d92..2cdf66e6d1b0 100644
> --- a/arch/x86/kvm/vmx/vmx.h
> +++ b/arch/x86/kvm/vmx/vmx.h
> @@ -148,6 +148,15 @@ struct nested_vmx {
> bool need_vmcs12_to_shadow_sync;
> bool dirty_vmcs12;
>
> + /*
> + * Indicates whether MSR bitmap for L2 needs to be rebuilt due to
> + * changes in MSR bitmap for L1 or switching to a different L2. Note,
> + * this flag can only be used reliably in conjunction with a paravirt L1
> + * which informs L0 whether any changes to MSR bitmap for L2 were done
> + * on its side.
> + */
> + bool msr_bitmap_force_recalc;

Belated bikeshedding... What about need_msr_bitmap_recalc to follow the above
need_vmcs12_to_shadow_sync?

> +
> /*
> * Indicates lazily loaded guest state has not yet been decached from
> * vmcs02.
> --
> 2.31.1
>