diff options
| -rw-r--r-- | mm/page_alloc.c | 25 |
1 files changed, 17 insertions, 8 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 6d1c8b06b458..087ba3e417ec 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1024,24 +1024,33 @@ void __meminit reserve_bootmem_region(unsigned long start, unsigned long end) static bool free_pages_prepare(struct page *page, unsigned int order) { - bool compound = PageCompound(page); - int i, bad = 0; + int bad = 0; VM_BUG_ON_PAGE(PageTail(page), page); - VM_BUG_ON_PAGE(compound && compound_order(page) != order, page); trace_mm_page_free(page, order); kmemcheck_free_shadow(page, order); kasan_free_pages(page, order); + /* + * Check tail pages before head page information is cleared to + * avoid checking PageCompound for order-0 pages. + */ + if (unlikely(order)) { + bool compound = PageCompound(page); + int i; + + VM_BUG_ON_PAGE(compound && compound_order(page) != order, page); + + for (i = 1; i < (1 << order); i++) { + if (compound) + bad += free_tail_pages_check(page, page + i); + bad += free_pages_check(page + i); + } + } if (PageAnon(page)) page->mapping = NULL; bad += free_pages_check(page); - for (i = 1; i < (1 << order); i++) { - if (compound) - bad += free_tail_pages_check(page, page + i); - bad += free_pages_check(page + i); - } if (bad) return false; |