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charset=UTF-8 Content-Transfer-Encoding: 7bit On 1/8/26 11:05, Ackerley Tng wrote: ... >> All of those properties are important and they're *GONE* if you use a >> pfn. It's even worse if you use a raw physical address. > > We were thinking through what it would take to have TDs use VM_PFNMAP > memory, where the memory may not actually have associated struct > pages. Without further work, having struct pages in the TDX interface > would kind of lock out those sources of memory. Is TDX open to using > non-kernel managed memory? I was afraid someone was going to bring that up. I'm not open to such a beast today. I'd certainly look at the patches, but it would be a hard sell and it would need an awfully strong justification. > For type safety, would phyrs help? [1] Perhaps starting with pfn/paddrs > + nr_pages would allow transitioning to phyrs later. Using pages would > be okay for now, but I would rather not use folios. I don't have any first-hand experience with phyrs. It seems interesting, but might be unwieldy to use in practice, kinda how the proposed code got messy when folios got thrown in.