diff --git a/mm/slab.c b/mm/slab.c
index 2046da2..e3260db 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -592,6 +592,7 @@
 {
 	if (unlikely(PageCompound(page)))
 		page = (struct page *)page_private(page);
+	BUG_ON(!PageSlab(page));
 	return (struct kmem_cache *)page->lru.next;
 }
 
@@ -604,6 +605,7 @@
 {
 	if (unlikely(PageCompound(page)))
 		page = (struct page *)page_private(page);
+	BUG_ON(!PageSlab(page));
 	return (struct slab *)page->lru.prev;
 }
 
@@ -2669,15 +2671,6 @@
 	kfree_debugcheck(objp);
 	page = virt_to_page(objp);
 
-	if (page_get_cache(page) != cachep) {
-		printk(KERN_ERR "mismatch in kmem_cache_free: expected "
-				"cache %p, got %p\n",
-		       page_get_cache(page), cachep);
-		printk(KERN_ERR "%p is %s.\n", cachep, cachep->name);
-		printk(KERN_ERR "%p is %s.\n", page_get_cache(page),
-		       page_get_cache(page)->name);
-		WARN_ON(1);
-	}
 	slabp = page_get_slab(page);
 
 	if (cachep->flags & SLAB_RED_ZONE) {
@@ -3393,6 +3386,8 @@
 {
 	unsigned long flags;
 
+	BUG_ON(virt_to_cache(objp) != cachep);
+
 	local_irq_save(flags);
 	__cache_free(cachep, objp);
 	local_irq_restore(flags);