Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753444AbbKZSJg (ORCPT ); Thu, 26 Nov 2015 13:09:36 -0500 Received: from mail-lf0-f46.google.com ([209.85.215.46]:34196 "EHLO mail-lf0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753309AbbKZSI2 (ORCPT ); Thu, 26 Nov 2015 13:08:28 -0500 From: Marcin Wojtas To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, netdev@vger.kernel.org Cc: davem@davemloft.net, linux@arm.linux.org.uk, sebastian.hesselbarth@gmail.com, andrew@lunn.ch, jason@lakedaemon.net, thomas.petazzoni@free-electrons.com, gregory.clement@free-electrons.com, simon.guinot@sequanux.org, nadavh@marvell.com, alior@marvell.com, xswang@marvell.com, myair@marvell.com, nitroshift@yahoo.com, mw@semihalf.com, jaz@semihalf.com, tn@semihalf.com, Subject: [PATCH v2 net 4/6] net: mvneta: fix error path for building skb Date: Thu, 26 Nov 2015 19:08:11 +0100 Message-Id: <1448561293-16431-5-git-send-email-mw@semihalf.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1448561293-16431-1-git-send-email-mw@semihalf.com> References: <1448561293-16431-1-git-send-email-mw@semihalf.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1647 Lines: 47 In the actual RX processing, there is same error path for both descriptor ring refilling and building skb fails. This is not correct, because after successful refill, the ring is already updated with newly allocated buffer. Then, in case of build_skb() fail, hitherto code left the original buffer unmapped. This patch fixes above situation by swapping error check of skb build with DMA-unmap of original buffer. Signed-off-by: Marcin Wojtas Cc: # v4.2+ Fixes a84e32894191 ("net: mvneta: fix refilling for Rx DMA buffers") --- drivers/net/ethernet/marvell/mvneta.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index 0c3d923..62cf971 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -1580,12 +1580,16 @@ static int mvneta_rx(struct mvneta_port *pp, int rx_todo, } skb = build_skb(data, pp->frag_size > PAGE_SIZE ? 0 : pp->frag_size); - if (!skb) - goto err_drop_frame; + /* After refill old buffer has to be unmapped regardless + * the skb is successfully built or not. + */ dma_unmap_single(dev->dev.parent, phys_addr, MVNETA_RX_BUF_SIZE(pp->pkt_size), DMA_FROM_DEVICE); + if (!skb) + goto err_drop_frame; + rcvd_pkts++; rcvd_bytes += rx_bytes; -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/