slub: enforce MAX_ORDER
slub_max_order may not be equal to or greater than MAX_ORDER.
Additionally, if a single object cannot be placed in a slab of
slub_max_order, it still must allocate slabs below MAX_ORDER.
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
diff --git a/mm/slub.c b/mm/slub.c
index 7ab54ec..0e1247e 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1909,7 +1909,7 @@
* Doh this slab cannot be placed using slub_max_order.
*/
order = slab_order(size, 1, MAX_ORDER, 1);
- if (order <= MAX_ORDER)
+ if (order < MAX_ORDER)
return order;
return -ENOSYS;
}
@@ -2522,6 +2522,7 @@
static int __init setup_slub_max_order(char *str)
{
get_option(&str, &slub_max_order);
+ slub_max_order = min(slub_max_order, MAX_ORDER - 1);
return 1;
}