Re: [RFC PATCH v5 16/45] x86/virt/tdx: Add tdx_alloc/free_control_page() helpers
From: Sean Christopherson
Date: Thu Feb 05 2026 - 17:38:04 EST
On Thu, Feb 05, 2026, Yan Zhao wrote:
> > diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
> > index f6e80aba5895..682c8a228b53 100644
> > --- a/arch/x86/virt/vmx/tdx/tdx.c
> > +++ b/arch/x86/virt/vmx/tdx/tdx.c
> > @@ -1824,6 +1824,50 @@ u64 tdh_mng_rd(struct tdx_td *td, u64 field, u64 *data)
> > }
> > EXPORT_SYMBOL_FOR_KVM(tdh_mng_rd);
> >
> > +/* Number PAMT pages to be provided to TDX module per 2M region of PA */
> > +static int tdx_dpamt_entry_pages(void)
> > +{
> > + if (!tdx_supports_dynamic_pamt(&tdx_sysinfo))
> > + return 0;
> > +
> This function is not invoked when !tdx_supports_dynamic_pamt().
> So, probably we can just return the count below?
Or maybe WARN_ON_ONCE() and return 0? I have no strong preference.
> > + return tdx_sysinfo.tdmr.pamt_4k_entry_size * PTRS_PER_PTE / PAGE_SIZE;
> > +}
> > +
>