From: Paul Burton <paul.burton@xxxxxxxxxx> 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 <paul.burton@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/ti/cpmac.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/ti/cpmac.c b/drivers/net/ethernet/ti/cpmac.c index 44d5a7bee0d7..755ddd586189 100644 --- a/drivers/net/ethernet/ti/cpmac.c +++ b/drivers/net/ethernet/ti/cpmac.c @@ -543,7 +543,8 @@ 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); @@ -553,7 +554,7 @@ static int cpmac_start_xmit(struct sk_buff *skb, struct net_device *dev) 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); -- 2.9.0