mm: fix madivse_pageout mishandling on non-LRU page

MADV_PAGEOUT tries to isolate non-LRU pages and gets a warning from isolate_lru_page below. Fix it by checking PageLRU in advance. ------------[ cut here ]------------ trying to isolate tail page WARNING: CPU: 0 PID: 6175 at mm/folio-compat.c:158 isolate_lru_page+0x130/0x140 Modules linked in: CPU: 0 PID: 6175 Comm: syz-executor.0 Not tainted 5.18.12 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:isolate_lru_page+0x130/0x140 Link: https://lore.kernel.org/linux-mm/[email protected]/ Link: https://lkml.kernel.org/r/[email protected] Fixes: 1a4e58c ("mm: introduce MADV_PAGEOUT") Signed-off-by: Minchan Kim <[email protected]> Reported-by: 韩天ç`� <[email protected]> Suggested-by: Yang Shi <[email protected]> Acked-by: Yang Shi <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
otyshchenko1 · Sep 26, 2022 · 58d426a · 58d426a
1 parent bedf034
commit 58d426a
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/mm/madvise.c b/mm/madvise.c
@@ -451,8 +451,11 @@ static int madvise_cold_or_pageout_pte_range(pmd_t *pmd,
 			continue;
 		}
 
-		/* Do not interfere with other mappings of this page */
-		if (page_mapcount(page) != 1)
+		/*
+		 * Do not interfere with other mappings of this page and
+		 * non-LRU page.
+		 */
+		if (!PageLRU(page) || page_mapcount(page) != 1)
 			continue;
 
 		VM_BUG_ON_PAGE(PageTransCompound(page), page);