diff options
Diffstat (limited to 'mm/rmap.c')
| -rw-r--r-- | mm/rmap.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/mm/rmap.c b/mm/rmap.c index 15a55304aa3b..846fc79f3ca9 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -490,6 +490,12 @@ void __init anon_vma_init(void) * page_remove_rmap() that the anon_vma pointer from page->mapping is valid * if there is a mapcount, we can dereference the anon_vma after observing * those. + * + * NOTE: the caller should normally hold folio lock when calling this. If + * not, the caller needs to double check the anon_vma didn't change after + * taking the anon_vma lock for either read or write (UFFDIO_MOVE can modify it + * concurrently without folio lock protection). See folio_lock_anon_vma_read() + * which has already covered that, and comment above remap_pages(). */ struct anon_vma *folio_get_anon_vma(struct folio *folio) { |