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

Vitaly Kuznetsov
2021-11-05T12:06:27Z

Sean Christopherson <seanjc@google.com> writes:

> 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?
>

'msr_bitmap_force_recalc' was suggested by Paolo but
'need_msr_bitmap_recalc' sounds equally good to me.

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

--
Vitaly