Re: [PATCH v2 13/15] KVM: x86/tdp_mmu: Make mmu notifier callbacks to check kvm_process

[Edgecombe, Rick P]

On Fri, 2024-06-07 at 10:56 +0200, Paolo Bonzini wrote:
> Subject: propagate enum kvm_process to MMU notifier callbacks
> 
> But again, the naming... I don't like kvm_process - in an OS process
> is a word with a clear meaning. Yes, that is a noun and this is a
> verb, but then naming an enum with a verb is also awkward.
> 
> Perhaps kvm_gfn_range_filter and range->attr_filter? A bit wordy but very
> clear:
> 
> enum kvm_tdp_mmu_root_types types =
>     kvm_gfn_range_filter_to_root_types(kvm, range->attr_filter)
> 
> I think I like it.

Agree 'process' sticks out. Somehow having attr_filter and args.attributes in
the same struct feels a bit wrong. Not that process was a lot better.

I guess attr_filter is more about alias ranges, and args.attribute is more about
conversion to various types of memory (private, shared and ideas of other types
I guess). But since today we only have private and shared, I wonder if there is
some way to combine them within struct kvm_gfn_range? I've not thought this all
the way through.

> 
> This patch also should be earlier in the series; please move it after
> patch 9, i.e. right after kvm_process_to_root_types is introduced.

Hmm, I thought I remembered having to move this to be later, but I don't see any
problems moving it earlier. Thanks for pointing it out.