diff options
Diffstat (limited to 'arch/s390/mm/gup.c')
| -rw-r--r-- | arch/s390/mm/gup.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c index 05c8abd864f1..9bce54eac0b0 100644 --- a/arch/s390/mm/gup.c +++ b/arch/s390/mm/gup.c @@ -39,7 +39,8 @@ static inline int gup_pte_range(pmd_t *pmdp, pmd_t pmd, unsigned long addr, VM_BUG_ON(!pfn_valid(pte_pfn(pte))); page = pte_page(pte); head = compound_head(page); - if (!page_cache_get_speculative(head)) + if (unlikely(WARN_ON_ONCE(page_ref_count(head) < 0) + || !page_cache_get_speculative(head))) return 0; if (unlikely(pte_val(pte) != pte_val(*ptep))) { put_page(head); @@ -77,7 +78,8 @@ static inline int gup_huge_pmd(pmd_t *pmdp, pmd_t pmd, unsigned long addr, refs++; } while (addr += PAGE_SIZE, addr != end); - if (!page_cache_add_speculative(head, refs)) { + if (unlikely(WARN_ON_ONCE(page_ref_count(head) < 0) + || !page_cache_add_speculative(head, refs))) { *nr -= refs; return 0; } @@ -151,7 +153,8 @@ static int gup_huge_pud(pud_t *pudp, pud_t pud, unsigned long addr, refs++; } while (addr += PAGE_SIZE, addr != end); - if (!page_cache_add_speculative(head, refs)) { + if (unlikely(WARN_ON_ONCE(page_ref_count(head) < 0) + || !page_cache_add_speculative(head, refs))) { *nr -= refs; return 0; } |