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Sashiko AI review found 1 potential issue to consider: - [Medium] mm/khugepaged: missing folio_is_common_memory() check in collapse_file() -- commit 5cdd71b37e4c9e4d2c7bf61d7c51d7ba89a07fb5 Author: Gregory Price (Meta) mm/khugepaged: restrict collapse to common memory This commit replaces the zone_device checks in anonymous THP scan and isolation paths with page_is_common_memory() and adds a folio_is_common_memory() check to collapse_scan_file(). > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index 4bbe319ef86fa..b4bd29f25c145 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c [ ... ] > @@ -2741,6 +2741,12 @@ static enum scan_result collapse_scan_file(struct = mm_struct *mm, > break; > } > =20 > + if (unlikely(!folio_is_common_memory(folio))) { > + result =3D SCAN_PAGE_NULL; > + failed_pfn =3D folio_pfn(folio); > + folio_put(folio); > + break; > + } > node =3D folio_nid(folio); > if (collapse_scan_abort(node, cc)) { > result =3D SCAN_SCAN_ABORT; [Severity: Medium] Should collapse_file() also check folio_is_common_memory(folio) after locking each folio, matching __collapse_huge_page_isolate()? collapse_scan_file() drops its folio reference on each iteration and skips missing page-cache indices and swapped-out shmem entries, and collapse_single_pmd() drops mmap_read_lock() before calling collapse_pmd() -> collapse_file(). Folios that are faulted into holes, migrated, or instantiated by shmem_get_folio() or page_cache_sync_readahead() on a node outside N_MEMORY_COMMON after the pre-scan will still be isolated and collapsed by collapse_file(). --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261114070959.3490= 008-1-gourry@gourry.net?part=3D10