pci_alloc_consistent calls dma_alloc_coherent directly.
In commit 
518a2f1925c3
("dma-mapping: zero memory returned from dma_alloc_*"),
dma_alloc_coherent has already zeroed the memory.
So memset is not needed.
Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
 
                goto error;
        }
        rrpriv->rx_ctrl_dma = dma_addr;
-       memset(rrpriv->rx_ctrl, 0, 256*sizeof(struct ring_ctrl));
 
        rrpriv->info = pci_alloc_consistent(pdev, sizeof(struct rr_info),
                                            &dma_addr);
                goto error;
        }
        rrpriv->info_dma = dma_addr;
-       memset(rrpriv->info, 0, sizeof(struct rr_info));
        wmb();
 
        spin_lock_irqsave(&rrpriv->lock, flags);