diff options
Diffstat (limited to 'mm/hugetlb.c')
| -rw-r--r-- | mm/hugetlb.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 3b08e34a775d..fe15e7d8220a 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4338,10 +4338,20 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, struct page *page; if (!*pagep) { - ret = -ENOMEM; + /* If a page already exists, then it's UFFDIO_COPY for + * a non-missing case. Return -EEXIST. + */ + if (vm_shared && + hugetlbfs_pagecache_present(h, dst_vma, dst_addr)) { + ret = -EEXIST; + goto out; + } + page = alloc_huge_page(dst_vma, dst_addr, 0); - if (IS_ERR(page)) + if (IS_ERR(page)) { + ret = -ENOMEM; goto out; + } ret = copy_huge_page_from_user(page, (const void __user *) src_addr, |