From: Marcin Wojtas <mw@semihalf.com>
Date: Thu, 3 Dec 2015 14:20:49 +0000 (+0100)
Subject: net: mvpp2: fix missing DMA region unmap in egress processing
X-Git-Tag: v4.4~75^2~80^2~2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=e864b4c7b184bde36fa6a02bb3190983d2f796f9;p=platform%2Fkernel%2Flinux-amlogic.git

net: mvpp2: fix missing DMA region unmap in egress processing

The Tx descriptor release code currently calls dma_unmap_single() and
dev_kfree_skb_any() if the descriptor is associated with a non-NULL skb.
This condition is true only for the last fragment of the packet.

Since every descriptor's buffer is DMA-mapped it has to be properly
unmapped.

Signed-off-by: Marcin Wojtas <mw@semihalf.com>

Fixes: 3f518509dedc ("ethernet: Add new driver for Marvell Armada 375
network unit")

Cc: <stable@vger.kernel.org> # v3.18+
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/net/ethernet/marvell/mvpp2.c b/drivers/net/ethernet/marvell/mvpp2.c
index d9884fd..95db519 100644
--- a/drivers/net/ethernet/marvell/mvpp2.c
+++ b/drivers/net/ethernet/marvell/mvpp2.c
@@ -4401,11 +4401,10 @@ static void mvpp2_txq_bufs_free(struct mvpp2_port *port,
 
 		mvpp2_txq_inc_get(txq_pcpu);
 
-		if (!skb)
-			continue;
-
 		dma_unmap_single(port->dev->dev.parent, buf_phys_addr,
 				 skb_headlen(skb), DMA_TO_DEVICE);
+		if (!skb)
+			continue;
 		dev_kfree_skb_any(skb);
 	}
 }