diff options
| -rw-r--r-- | mm/hugetlb.c | 3 | ||||
| -rw-r--r-- | mm/memory.c | 8 | ||||
| -rw-r--r-- | mm/mprotect.c | 8 |
3 files changed, 16 insertions, 3 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 7fcdb98c9e68..bdbfeb6fb393 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5051,6 +5051,9 @@ again: entry = huge_pte_clear_uffd_wp(entry); set_huge_pte_at(dst, addr, dst_pte, entry); } else if (unlikely(is_pte_marker(entry))) { + /* No swap on hugetlb */ + WARN_ON_ONCE( + is_swapin_error_entry(pte_to_swp_entry(entry))); /* * We copy the pte marker only if the dst vma has * uffd-wp enabled. diff --git a/mm/memory.c b/mm/memory.c index 032ef700c3e8..3e836fecd035 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -828,7 +828,7 @@ copy_nonpresent_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, return -EBUSY; return -ENOENT; } else if (is_pte_marker_entry(entry)) { - if (userfaultfd_wp(dst_vma)) + if (is_swapin_error_entry(entry) || userfaultfd_wp(dst_vma)) set_pte_at(dst_mm, addr, dst_pte, pte); return 0; } @@ -3625,8 +3625,12 @@ static vm_fault_t pte_marker_clear(struct vm_fault *vmf) /* * Be careful so that we will only recover a special uffd-wp pte into a * none pte. Otherwise it means the pte could have changed, so retry. + * + * This should also cover the case where e.g. the pte changed + * quickly from a PTE_MARKER_UFFD_WP into PTE_MARKER_SWAPIN_ERROR. + * So is_pte_marker() check is not enough to safely drop the pte. */ - if (is_pte_marker(*vmf->pte)) + if (pte_same(vmf->orig_pte, *vmf->pte)) pte_clear(vmf->vma->vm_mm, vmf->address, vmf->pte); pte_unmap_unlock(vmf->pte, vmf->ptl); return 0; diff --git a/mm/mprotect.c b/mm/mprotect.c index 908df12caa26..61cf60015a8b 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -245,7 +245,13 @@ static unsigned long change_pte_range(struct mmu_gather *tlb, newpte = pte_swp_mksoft_dirty(newpte); if (pte_swp_uffd_wp(oldpte)) newpte = pte_swp_mkuffd_wp(newpte); - } else if (pte_marker_entry_uffd_wp(entry)) { + } else if (is_pte_marker_entry(entry)) { + /* + * Ignore swapin errors unconditionally, + * because any access should sigbus anyway. + */ + if (is_swapin_error_entry(entry)) + continue; /* * If this is uffd-wp pte marker and we'd like * to unprotect it, drop it; the next page |