Re: [PATCH v19 011/130] KVM: Add new members to struct kvm_gfn_range to operate on

From: Edgecombe, Rick P
Date: Fri Apr 26 2024 - 09:51:04 EST


On Fri, 2024-04-26 at 08:39 +0100, Fuad Tabba wrote:
> > I'm fine with those names. Anyway, I'm fine with wither way, two bools or
> > enum.
>
> I don't have a strong opinion, but I'd brought it up in a previous
> patch series. I think that having two bools to encode three states is
> less intuitive and potentially more bug prone, more so than the naming
> itself (i.e., _only):
> https://lore.kernel.org/all/ZUO1Giju0GkUdF0o@xxxxxxxxxx/

Currently in our internal branch we switched to:
exclude_private
exclude_shared

It came together bettter in the code that uses it.

But I started to wonder if we actually really need exclude_shared. For TDX
zapping private memory has to be done with more care, because it cannot be re-
populated without guest coordination. But for shared memory if we are zapping a
range that includes both private and shared memory, I don't think it should hurt
to zap the shared memory.