Re: [PATCH] mm: Add additional consistency check

From: Christoph Lameter
Date: Tue Apr 11 2017 - 12:16:51 EST


On Tue, 11 Apr 2017, Michal Hocko wrote:

> static inline void *index_to_obj(struct kmem_cache *cache, struct page *page,
> @@ -3813,14 +3818,18 @@ void kfree(const void *objp)
> {
> struct kmem_cache *c;
> unsigned long flags;
> + struct page *page;
>
> trace_kfree(_RET_IP_, objp);
>
> if (unlikely(ZERO_OR_NULL_PTR(objp)))
> return;
> + page = virt_to_head_page(obj);
> + if (CHECK_DATA_CORRUPTION(!PageSlab(page)))

There is a flag SLAB_DEBUG_OBJECTS that is available for this check.
Consistency checks are configuraable in the slab allocator.

Mentioned that before and got this lecture about data consistency checks.