Re: [PATCH 1/3] VFIO: take reference to the KVM module

Sean Christopherson
2026-04-16T00:31:31Z

On Fri, Apr 10, 2026, Dan Williams wrote:
> Sean Christopherson wrote:
> > +Dan
>
> +Yilun
>
> [..]
> > I added Dan because the PCI TSM stuff is picking up "struct kvm *kvm" references,
> > and I want to head that off too, i.e. have it use the file approach instead of
> > whatever it plans on doing (can't tell from the code, because there are no users).
>
> The PCI TSM *reference* for 'struct kvm *' will be inherited from
> vfio/iommufd. However, the TSM driver needs some context to manipulate

I assume/hope it just need to read "struct kvm" state though?

> the VM. For example, TDX effectively needs:
>
> to_kvm_tdx(kvm)->td.tdr_page
>
> ...for operations like TDH.TDI.CREATE that sets up the context for the
> privately assigned device.
>
> It could follow the example of arch/x86/kvm/mmu/page_track.c and do:
>
> kvm_tdx_tdi_create(struct file *kvm, ...)
>
> ...and use file_to_kvm() for that limited helper that does not need to expose
> 'struct kvm_tdx' outside of arch/x86/.

Any idea how many assets do you anticipate needing? E.g. is it just the TDR
page, or will TSM need a whole pile of information?