Let's simplify and only print the page mapcount: we already print the large folio mapcount and the entire folio mapcount for large folios separately; that should be sufficient to figure out what's happening. While at it, print the page mapcount also if it had an underflow, filtering out only typed pages. Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> --- mm/debug.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/mm/debug.c b/mm/debug.c index d064db42af54..69e524c3e601 100644 --- a/mm/debug.c +++ b/mm/debug.c @@ -55,15 +55,10 @@ static void __dump_folio(struct folio *folio, struct page *page, unsigned long pfn, unsigned long idx) { struct address_space *mapping = folio_mapping(folio); - int mapcount = atomic_read(&page->_mapcount) + 1; + int mapcount = atomic_read(&page->_mapcount); char *type = ""; - /* Open-code page_mapcount() to avoid looking up a stale folio */ - if (mapcount < 0) - mapcount = 0; - if (folio_test_large(folio)) - mapcount += folio_entire_mapcount(folio); - + mapcount = page_type_has_type(mapcount) ? 0 : mapcount + 1; pr_warn("page: refcount:%d mapcount:%d mapping:%p index:%#lx pfn:%#lx\n", folio_ref_count(folio), mapcount, mapping, folio->index + idx, pfn); -- 2.44.0