From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Paul Burton , "David S. Miller" Subject: [PATCH 4.4 097/101] net: ti: cpmac: Fix compiler warning due to type confusion Date: Tue, 10 Jan 2017 14:37:50 +0100 Message-Id: <20170110131526.549351770@linuxfoundation.org> In-Reply-To: <20170110131522.493717794@linuxfoundation.org> References: <20170110131522.493717794@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paul Burton commit 2f5281ba2a8feaf6f0aee93356f350855bb530fc upstream. cpmac_start_xmit() used the max() macro on skb->len (an unsigned int) and ETH_ZLEN (a signed int literal). This led to the following compiler warning: In file included from include/linux/list.h:8:0, from include/linux/module.h:9, from drivers/net/ethernet/ti/cpmac.c:19: drivers/net/ethernet/ti/cpmac.c: In function 'cpmac_start_xmit': include/linux/kernel.h:748:17: warning: comparison of distinct pointer types lacks a cast (void) (&_max1 == &_max2); \ ^ drivers/net/ethernet/ti/cpmac.c:560:8: note: in expansion of macro 'max' len = max(skb->len, ETH_ZLEN); ^ On top of this, it assigned the result of the max() macro to a signed integer whilst all further uses of it result in it being cast to varying widths of unsigned integer. Fix this up by using max_t to ensure the comparison is performed as unsigned integers, and for consistency change the type of the len variable to unsigned int. Signed-off-by: Paul Burton Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/ti/cpmac.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/net/ethernet/ti/cpmac.c +++ b/drivers/net/ethernet/ti/cpmac.c @@ -549,7 +549,8 @@ fatal_error: static int cpmac_start_xmit(struct sk_buff *skb, struct net_device *dev) { - int queue, len; + int queue; + unsigned int len; struct cpmac_desc *desc; struct cpmac_priv *priv = netdev_priv(dev); @@ -559,7 +560,7 @@ static int cpmac_start_xmit(struct sk_bu if (unlikely(skb_padto(skb, ETH_ZLEN))) return NETDEV_TX_OK; - len = max(skb->len, ETH_ZLEN); + len = max_t(unsigned int, skb->len, ETH_ZLEN); queue = skb_get_queue_mapping(skb); netif_stop_subqueue(dev, queue);