diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c index 13dab0c1645c..3776aca22082 100644 --- a/arch/s390/mm/gup.c +++ b/arch/s390/mm/gup.c @@ -20,9 +20,9 @@ static inline int gup_pte_range(pmd_t *pmdp, pmd_t pmd, unsigned long addr, unsigned long end, int write, struct page **pages, int *nr) { + struct page *head, *page; unsigned long mask; pte_t *ptep, pte; - struct page *page; mask = (write ? _PAGE_PROTECT : 0) | _PAGE_INVALID | _PAGE_SPECIAL; @@ -37,12 +37,14 @@ static inline int gup_pte_range(pmd_t *pmdp, pmd_t pmd, unsigned long addr, return 0; VM_BUG_ON(!pfn_valid(pte_pfn(pte))); page = pte_page(pte); - if (!page_cache_get_speculative(page)) + head = compound_head(page); + if (!page_cache_get_speculative(head)) return 0; if (unlikely(pte_val(pte) != pte_val(*ptep))) { - put_page(page); + put_page(head); return 0; } + VM_BUG_ON_PAGE(compound_head(page) != head, page); pages[*nr] = page; (*nr)++;