The quilt patch titled Subject: mm/gup: fix memfd_pin_folios hugetlb page allocation has been removed from the -mm tree. Its filename was mm-gup-fix-memfd_pin_folios-hugetlb-page-allocation.patch

This patch was dropped because it was merged into the mm-hotfixes-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------ From: Steve Sistare steven.sistare@oracle.com Subject: mm/gup: fix memfd_pin_folios hugetlb page allocation Date: Tue, 3 Sep 2024 07:25:20 -0700

When memfd_pin_folios -> memfd_alloc_folio creates a hugetlb page, the index is wrong. The subsequent call to filemap_get_folios_contig thus cannot find it, and fails, and memfd_pin_folios loops forever. To fix, adjust the index for the huge_page_order.

memfd_alloc_folio also forgets to unlock the folio, so the next touch of the page calls hugetlb_fault which blocks forever trying to take the lock. Unlock it.

Link: https://lkml.kernel.org/r/1725373521-451395-5-git-send-email-steven.sistare@... Fixes: 89c1905d9c14 ("mm/gup: introduce memfd_pin_folios() for pinning memfd folios") Signed-off-by: Steve Sistare steven.sistare@oracle.com Acked-by: Vivek Kasireddy vivek.kasireddy@intel.com Cc: David Hildenbrand david@redhat.com Cc: Jason Gunthorpe jgg@nvidia.com Cc: Matthew Wilcox willy@infradead.org Cc: Muchun Song muchun.song@linux.dev Cc: Peter Xu peterx@redhat.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/memfd.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)

--- a/mm/memfd.c~mm-gup-fix-memfd_pin_folios-hugetlb-page-allocation +++ a/mm/memfd.c @@ -79,10 +79,13 @@ struct folio *memfd_alloc_folio(struct f * alloc from. Also, the folio will be pinned for an indefinite * amount of time, so it is not expected to be migrated away. */ - gfp_mask = htlb_alloc_mask(hstate_file(memfd)); + struct hstate *h = hstate_file(memfd); + + gfp_mask = htlb_alloc_mask(h); gfp_mask &= ~(__GFP_HIGHMEM | __GFP_MOVABLE); + idx >>= huge_page_order(h);

- folio = alloc_hugetlb_folio_reserve(hstate_file(memfd), + folio = alloc_hugetlb_folio_reserve(h, numa_node_id(), NULL, gfp_mask); @@ -95,6 +98,7 @@ struct folio *memfd_alloc_folio(struct f free_huge_folio(folio); return ERR_PTR(err); } + folio_unlock(folio); return folio; } return ERR_PTR(-ENOMEM); _

Patches currently in -mm which might be from steven.sistare@oracle.com are