Re: [Question] A novel case happened when using mempool allocate memory.

From: Matthew Wilcox
Date: Wed Aug 01 2018 - 11:37:28 EST


On Wed, Aug 01, 2018 at 11:31:15PM +0800, zhong jiang wrote:
> Hi, Everyone
>
> I ran across the following novel case similar to memory leak in linux-4.1 stable when allocating
> memory object by kmem_cache_alloc. it rarely can be reproduced.
>
> I create a specific mempool with 24k size based on the slab. it can not be merged with
> other kmem cache. I record the allocation and free usage by atomic_add/sub. After a while,
> I watch the specific slab consume most of total memory. After halting the code execution.
> The counter of allocation and free is equal. Therefore, I am sure that module have released
> all meory resource. but the statistic of specific slab is very high but stable by checking /proc/slabinfo.

Please post the code.