diff options
| -rw-r--r-- | mm/memory.c | 9 | ||||
| -rw-r--r-- | mm/rmap.c | 4 | ||||
| -rw-r--r-- | mm/swapfile.c | 14 |
3 files changed, 24 insertions, 3 deletions
diff --git a/mm/memory.c b/mm/memory.c index a4fc6e632d2c..97ddba866e43 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4341,6 +4341,15 @@ check_folio: if (unlikely(folio != swapcache && swapcache)) { folio_add_new_anon_rmap(folio, vma, address, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); + } else if (!folio_test_anon(folio)) { + /* + * We currently only expect small !anon folios, which are either + * fully exclusive or fully shared. If we ever get large folios + * here, we have to be careful. + */ + VM_WARN_ON_ONCE(folio_test_large(folio)); + VM_WARN_ON_FOLIO(!folio_test_locked(folio), folio); + folio_add_new_anon_rmap(folio, vma, address, rmap_flags); } else { folio_add_anon_rmap_ptes(folio, page, nr_pages, vma, address, rmap_flags); diff --git a/mm/rmap.c b/mm/rmap.c index c0c99f91ade1..41012fe7a05a 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1422,7 +1422,9 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, VM_WARN_ON_FOLIO(!exclusive && !folio_test_locked(folio), folio); VM_BUG_ON_VMA(address < vma->vm_start || address + (nr << PAGE_SHIFT) > vma->vm_end, vma); - __folio_set_swapbacked(folio); + + if (!folio_test_swapbacked(folio)) + __folio_set_swapbacked(folio); __folio_set_anon(folio, vma, address, exclusive); if (likely(!folio_test_large(folio))) { diff --git a/mm/swapfile.c b/mm/swapfile.c index ae1d2700f6a3..38bdc439651a 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1908,8 +1908,18 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd, VM_BUG_ON_FOLIO(folio_test_writeback(folio), folio); if (pte_swp_exclusive(old_pte)) rmap_flags |= RMAP_EXCLUSIVE; - - folio_add_anon_rmap_pte(folio, page, vma, addr, rmap_flags); + /* + * We currently only expect small !anon folios, which are either + * fully exclusive or fully shared. If we ever get large folios + * here, we have to be careful. + */ + if (!folio_test_anon(folio)) { + VM_WARN_ON_ONCE(folio_test_large(folio)); + VM_WARN_ON_FOLIO(!folio_test_locked(folio), folio); + folio_add_new_anon_rmap(folio, vma, addr, rmap_flags); + } else { + folio_add_anon_rmap_pte(folio, page, vma, addr, rmap_flags); + } } else { /* ksm created a completely new copy */ folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); |