mm: make sure isolate_lru_page() is never called for tail page

The VM_BUG_ON_PAGE() would catch such cases if any still exists.

Signed-off-by: Kirill A. Shutemov <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/mm/vmscan.c b/mm/vmscan.c
index bb0cbd4c9f01f913a4779fd6ab3daf8bba4b207c..108bd119f2f6ba3f55247d7136684f937243b0c8 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1426,6 +1426,7 @@ int isolate_lru_page(struct page *page)
        int ret = -EBUSY;
 
        VM_BUG_ON_PAGE(!page_count(page), page);
+       VM_BUG_ON_PAGE(PageTail(page), page);
 
        if (PageLRU(page)) {
                struct zone *zone = page_zone(page);