On Thu, Aug 28, 2025 at 12:01:15AM +0200, David Hildenbrand wrote: >Let's limit the maximum folio size in problematic kernel config where >the memmap is allocated per memory section (SPARSEMEM without >SPARSEMEM_VMEMMAP) to a single memory section. > >Currently, only a single architectures supports ARCH_HAS_GIGANTIC_PAGE >but not SPARSEMEM_VMEMMAP: sh. > >Fortunately, the biggest hugetlb size sh supports is 64 MiB >(HUGETLB_PAGE_SIZE_64MB) and the section size is at least 64 MiB >(SECTION_SIZE_BITS == 26), so their use case is not degraded. > >As folios and memory sections are naturally aligned to their order-2 size >in memory, consequently a single folio can no longer span multiple memory >sections on these problematic kernel configs. > >nth_page() is no longer required when operating within a single compound >page / folio. > >Reviewed-by: Zi Yan <ziy@xxxxxxxxxx> >Acked-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx> >Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Reviewed-by: Wei Yang <richard.weiyang@xxxxxxxxx> -- Wei Yang Help you, Help me
