mm/slub: Add debugging to verify correct cache use on kmem_cache_free()

Add additional debugging to check that the objects is actually from the cache the caller claims. Doing so currently trips up some other debugging code. It takes a lot to infer from that what was happening. Reviewed-by: Glauber Costa <[email protected]> Signed-off-by: Christoph Lameter <[email protected]> [ [email protected]: Use pr_err() ] Signed-off-by: Pekka Enberg <[email protected]>
chewitt · Sep 5, 2012 · 7957610 · 7957610
1 parent e21827a
commit 7957610
Showing 1 changed file with 7 additions and 0 deletions.
diff --git a/mm/slub.c b/mm/slub.c
@@ -2614,6 +2614,13 @@ void kmem_cache_free(struct kmem_cache *s, void *x)
 
 	page = virt_to_head_page(x);
 
+	if (kmem_cache_debug(s) && page->slab != s) {
+		pr_err("kmem_cache_free: Wrong slab cache. %s but object"
+			" is from  %s\n", page->slab->name, s->name);
+		WARN_ON_ONCE(1);
+		return;
+	}
+
 	slab_free(s, page, x, _RET_IP_);
 
 	trace_kmem_cache_free(_RET_IP_, x);