diff options
Diffstat (limited to '')
| -rw-r--r-- | mm/hugetlb.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 4b8f413e011d..25f4ac5ca6fe 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5438,7 +5438,8 @@ static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma, static vm_fault_t hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma, struct address_space *mapping, pgoff_t idx, - unsigned long address, pte_t *ptep, unsigned int flags) + unsigned long address, pte_t *ptep, + pte_t old_pte, unsigned int flags) { struct hstate *h = hstate_vma(vma); vm_fault_t ret = VM_FAULT_SIGBUS; @@ -5565,7 +5566,8 @@ retry: ptl = huge_pte_lock(h, mm, ptep); ret = 0; - if (!huge_pte_none(huge_ptep_get(ptep))) + /* If pte changed from under us, retry */ + if (!pte_same(huge_ptep_get(ptep), old_pte)) goto backout; if (anon_rmap) { @@ -5575,6 +5577,12 @@ retry: page_dup_file_rmap(page, true); new_pte = make_huge_pte(vma, page, ((vma->vm_flags & VM_WRITE) && (vma->vm_flags & VM_SHARED))); + /* + * If this pte was previously wr-protected, keep it wr-protected even + * if populated. + */ + if (unlikely(pte_marker_uffd_wp(old_pte))) + new_pte = huge_pte_wrprotect(huge_pte_mkuffd_wp(new_pte)); set_huge_pte_at(mm, haddr, ptep, new_pte); hugetlb_count_add(pages_per_huge_page(h), mm); @@ -5692,8 +5700,10 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, mutex_lock(&hugetlb_fault_mutex_table[hash]); entry = huge_ptep_get(ptep); - if (huge_pte_none(entry)) { - ret = hugetlb_no_page(mm, vma, mapping, idx, address, ptep, flags); + /* PTE markers should be handled the same way as none pte */ + if (huge_pte_none_mostly(entry)) { + ret = hugetlb_no_page(mm, vma, mapping, idx, address, ptep, + entry, flags); goto out_mutex; } |