From 7a197d346a44384a1a858a98ef03766840e561d4 Mon Sep 17 00:00:00 2001 From: Jane Chu Date: Mon, 2 Mar 2026 13:10:15 -0700 Subject: [PATCH] Documentation: fix a hugetlbfs reservation statement Documentation/mm/hugetlbfs_reserv.rst has if (resv_needed <= (resv_huge_pages - free_huge_pages)) resv_huge_pages += resv_needed; which describes this code in gather_surplus_pages() needed = (h->resv_huge_pages + delta) - h->free_huge_pages; if (needed <= 0) { h->resv_huge_pages += delta; return 0; } which means if there are enough free hugepages to account for the new reservation, simply update the global reservation count without further action. But the description is backwards, it should be if (resv_needed <= (free_huge_pages - resv_huge_pages)) instead. Link: https://lkml.kernel.org/r/20260302201015.1824798-1-jane.chu@oracle.com Fixes: 70bc0dc578b3 ("Documentation: vm, add hugetlbfs reservation overview") Signed-off-by: Jane Chu Cc: David Hildenbrand Cc: Hillf Danton Cc: Jonathan Corbet Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mike Rapoport Cc: Muchun Song Cc: Oscar Salvador Cc: Shuah Khan Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- Documentation/mm/hugetlbfs_reserv.rst | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Documentation/mm/hugetlbfs_reserv.rst b/Documentation/mm/hugetlbfs_reserv.rst index 4914fbf07966..a49115db18c7 100644 --- a/Documentation/mm/hugetlbfs_reserv.rst +++ b/Documentation/mm/hugetlbfs_reserv.rst @@ -155,7 +155,7 @@ are enough free huge pages to accommodate the reservation. If there are, the global reservation count resv_huge_pages is adjusted something like the following:: - if (resv_needed <= (resv_huge_pages - free_huge_pages)) + if (resv_needed <= (free_huge_pages - resv_huge_pages) resv_huge_pages += resv_needed; Note that the global lock hugetlb_lock is held when checking and adjusting