On Mon, May 11, 2026 at 05:03:08AM -0400, Michael S. Tsirkin wrote: > gather_surplus_pages() pre-allocates hugetlb pages into the pool > during mmap. Pass __GFP_ZERO so these pages are zeroed by the > buddy allocator, and HPG_zeroed is set by alloc_surplus_hugetlb_folio. > > Add bool *zeroed output to alloc_hugetlb_folio_reserve() so > callers can check whether the pool page is known-zero. memfd's > memfd_alloc_folio() uses this to skip the explicit folio_zero_user() > when the page is already zero. > > This avoids redundant zeroing for memfd hugetlb pages that were > pre-allocated into the pool and never mapped to userspace. >
Same thing here, seems more like what's actually wanted is to sink the folio_user_zero stuff into hugetlb.c rather than make memfd.c request for zeroing - and then have to check again anyway. ~Gregory
