From: Zi Yan <ziy@xxxxxxxxxx> Whenever a buddy page is found, page_is_buddy() should be called to check its validity. Add the missing check during pageblock merge check. Fixes: 1dd214b8f21c ("mm: page_alloc: avoid merging non-fallbackable pageblocks with others") Reported-by: Steven Rostedt <rostedt@xxxxxxxxxxx> Signed-off-by: Zi Yan <ziy@xxxxxxxxxx> --- mm/page_alloc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index bdc8f60ae462..6c6af8658775 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1108,6 +1108,9 @@ static inline void __free_one_page(struct page *page, buddy_pfn = __find_buddy_pfn(pfn, order); buddy = page + (buddy_pfn - pfn); + + if (!page_is_buddy(page, buddy, order)) + goto done_merging; buddy_mt = get_pageblock_migratetype(buddy); if (migratetype != buddy_mt -- 2.35.1