[PATCH] slab: remove broken PageSlab check from kfree_debugcheck

The PageSlab debug check in kfree_debugcheck() is broken for compound
pages.  It is also redundant as we already do BUG_ON for non-slab pages in
page_get_cache() and page_get_slab() which are always called before we free
any actual objects.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/slab.c b/mm/slab.c
index c6100628a6ef7be2325a55e18f69b80a5a0f2006..aea1cd25314b7bbf446b8e8d3826dee5ed181259 100644 (file)
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -2814,19 +2814,11 @@ failed:
  */
 static void kfree_debugcheck(const void *objp)
 {
-       struct page *page;
-
        if (!virt_addr_valid(objp)) {
                printk(KERN_ERR "kfree_debugcheck: out of range ptr %lxh.\n",
                       (unsigned long)objp);
                BUG();
        }
-       page = virt_to_page(objp);
-       if (!PageSlab(page)) {
-               printk(KERN_ERR "kfree_debugcheck: bad ptr %lxh.\n",
-                      (unsigned long)objp);
-               BUG();
-       }
 }
 
 static inline void verify_redzone_free(struct kmem_cache *cache, void *obj)