Re: [PATCH 1/2] x86/virt/tdx: Use PFN directly for mapping guest private memory
From: Edgecombe, Rick P
Date: Thu Mar 19 2026 - 13:35:48 EST
On Thu, 2026-03-19 at 12:57 +0000, Kiryl Shutsemau wrote:
> > Though tdh_mem_page_aug() is an API, it is currently only exported to KVM
> > and
> > uses type kvm_pfn_t. So, is it still acceptable to assume flush size to be
> > PAGE_SIZE? Honoring level will soon be introduced by huge page patches.
>
> It caught my eye because previously size to flush was passed down to
> tdx_clflush_page() in the struct page (although never used there).
> With switching to pfn, we give up this information and it has to be
> passed separately. It would be easy to miss that in huge page patches,
> if we don't pass down level here.
>
> >
> > If you think it needs to be fixed before huge page series, what about fixing
> > it
> > in a separate cleanup patch? IMO, it would be better placed after Sean's
> > cleanup
> > patch [1], so we can use page_level_size() instead of inventing the wheel.
>
> I am okay with a separate patch.
I feel like we argued about this before. But it would be more correct to just
drop level and make it 4k only until huge pages? Otherwise we are tweaking dead
behavior.