[PATCH RFC 11/35] mm: sanity-check maximum folio size in folio_set_order()
David Hildenbrand <[email protected]>
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Let's sanity-check in folio_set_order() whether we would be trying to create a folio with an order that would make it exceed MAX_FOLIO_ORDER. This will enable the check whenever a folio/compound page is initialized through prepare_compound_head() / prepare_compound_page(). Signed-off-by: David Hildenbrand <[email protected]> --- mm/internal.h | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/internal.h b/mm/internal.h index 45b725c3dc030..946ce97036d67 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -755,6 +755,7 @@ static inline void folio_set_order(struct folio *folio, unsigned int order) { if (WARN_ON_ONCE(!order || !folio_test_large(folio))) return; + VM_WARN_ON_ONCE(order > MAX_FOLIO_ORDER); folio->_flags_1 = (folio->_flags_1 & ~0xffUL) | order; #ifdef NR_PAGES_IN_LARGE_FOLIO -- 2.50.1