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>+ struct tdx_hpa_list *hpa_list; >+ unsigned int added_pages; >+ struct page *page; >+ int ret; >+ >+ /* >+ * TDX module uses the metadata memory_pool_required_pages to indicate >+ * how much memory is still needed. This value decreases each time >+ * memory is added via TDH.EXT.MEM.ADD. >+ * >+ * On first time initialization, a value of 0 before any memory is >+ * added is unusual. But host makes no assumptions. Skip the memory >+ * setup and let subsequent steps catch any actual errors. >+ */ The fact that the value decreases on each TDH.EXT.MEM.ADD is not relevant here. Also, calling 0 "unusual" does not help the reader. It is either a valid value the kernel needs to handle, or an invalid one the kernel can assert on. How about: /* * The TDX module may require no memory at all. Skip the memory * setup in that case. */ >+ if (!required_pages) >+ return 0;