On Mon, Nov 6, 2023 at 11:46 PM Yunsheng Lin linyunsheng@huawei.com wrote:
On 2023/11/6 10:44, Mina Almasry wrote:
+void __netdev_devmem_binding_free(struct netdev_dmabuf_binding *binding) +{
size_t size, avail;gen_pool_for_each_chunk(binding->chunk_pool,netdev_devmem_free_chunk_owner, NULL);size = gen_pool_size(binding->chunk_pool);avail = gen_pool_avail(binding->chunk_pool);if (!WARN(size != avail, "can't destroy genpool. size=%lu, avail=%lu",size, avail))gen_pool_destroy(binding->chunk_pool);Is there any other place calling the gen_pool_destroy() when the above warning is triggered? Do we have a leaking for binding->chunk_pool?
gen_pool_destroy BUG_ON() if it's not empty at the time of destroying. Technically that should never happen, because __netdev_devmem_binding_free() should only be called when the refcount hits 0, so all the chunks have been freed back to the gen_pool. But, just in case, I don't want to crash the server just because I'm leaking a chunk... this is a bit of defensive programming that is typically frowned upon, but the behavior of gen_pool is so severe I think the WARN() + check is warranted here.
dma_buf_unmap_attachment(binding->attachment, binding->sgt,DMA_BIDIRECTIONAL);dma_buf_detach(binding->dmabuf, binding->attachment);dma_buf_put(binding->dmabuf);kfree(binding);+}