Re: [RFC PATCH V3 2/4] KVM: X86: Introduce role.glevel for level expanded pagetable

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wed, Apr 13, 2022 at 5:31 AM Sean Christopherson <seanjc@xxxxxxxxxx> wrote:

> >  union kvm_mmu_page_role {
> >       u32 word;
> > @@ -331,7 +331,8 @@ union kvm_mmu_page_role {
> >               unsigned smap_andnot_wp:1;
> >               unsigned ad_disabled:1;
> >               unsigned guest_mode:1;
> > -             unsigned :6;
> > +             unsigned glevel:4;
>
> We don't need 4 bits for this.  Crossing our fingers that we never had to shadow
> a 2-level guest with a 6-level host, we can do:
>
>                 unsigned passthrough_delta:2;

We can save the bits in the future when we need more bits so I didn't
hesitate to use 4 bits since glevel gives simple code. ^_^

I think the name passthrough_delta is more informative and glevel
is used only for comparison so passthrough_delta can also be
simple.  I will apply your suggestion.


Thanks
Lai



[Index of Archives]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Linux FS]     [Yosemite Forum]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Video 4 Linux]     [Device Mapper]     [Linux Resources]

  Powered by Linux