On Thu, Jun 13, 2019 at 10:57:45AM -0700, Song Liu wrote:
> @@ -419,6 +419,11 @@ static struct page *follow_pmd_mask(struct
> vm_area_struct *vma,
> put_page(page);
> if (pmd_none(*pmd))
> return no_page_table(vma, flags);
> + } else { /* flags & FOLL_SPLIT_PMD */
> + spin_unlock(ptl);
> + ret = 0;
> + split_huge_pmd(vma, pmd, address);
> + pte_alloc(mm, pmd);pte_alloc() can fail and the failure should be propogated to the caller. -- Kirill A. Shutemov
