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charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/15/24 12:20, Rick Edgecombe wrote: > +struct tdx_td { > + hpa_t tdr; > + hpa_t *tdcs; > +}; This is a step in the right direction because it gives the wrappers some more type safety. But an hpa_t is _barely_ better than a u64. If the 'tdr' is a page, then it needs to be _stored_ as a page: struct page *tdr_page; Also, please don't forget to spell these things out: /* TD root structure: */ struct page *tdr_page; And the tdcs is an array of pages, right? So it should be: struct page **tdcs_pages; Or heck, I _think_ it can theoretically be defined as a variable-length array: struct page *tdcs_pages[]; and use the helpers that we have for that. Putting it all together, you would have this: struct tdx_td { /* TD root structure: */ struct page *tdr_page; int tdcs_nr_pages; /* TD control structure: */ struct page *tdcs_pages[]; }; That's *MUCH* harder to misuse. It's 100% obvious that you have a single page, plus a variable-length array of pages. This is all from just looking at the structure definition. You know that 'tdr' is not just some random physical address. It's a whole physical page. It's page-aligned. It was allocated, from the allocator. It doesn't point to special memory. Ditto for "hpa_t *tdcs". It's not obvious from the data structure that it's an array or if it's an array how it got allocated or how large it is.