From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Perches <joe@perches.com>
Subject: Re: [PATCH 2/2] ksz884x: fix Endian
Date: Sun, 08 Jul 2012 22:44:56 -0700
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Cc: Ben Hutchings <bhutchings@solarflare.com>, netdev@vger.kernel.org,
	Tristram.Ha@micrel.com
To: RongQing Li <roy.qing.li@gmail.com>
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On Mon, 2012-07-09 at 13:26 +0800, RongQing Li wrote:
> 2012/7/7, Ben Hutchings <bhutchings@solarflare.com>:
> > On Thu, 2012-07-05 at 10:06 +0800, roy.qing.li@gmail.com wrote:
> >> ETH_P_IP is host Endian, skb->protocol is big Endian, when
> >> compare them, we should change skb->protocol from big endian
> >> to host endian, ntohs, not htons.
[]
> >> diff --git a/drivers/net/ethernet/micrel/ksz884x.c
[]
> >> @@ -4882,7 +4882,7 @@ static netdev_tx_t netdev_tx(struct sk_buff *skb,
> >> struct net_device *dev)
> >>  	if (left) {
> >>  		if (left < num ||
> >>  				((CHECKSUM_PARTIAL == skb->ip_summed) &&
> >> -				(ETH_P_IPV6 == htons(skb->protocol)))) {
> >> +				(ETH_P_IPV6 == ntohs(skb->protocol)))) {
> >
> > This should really be changed to the idiomatic 'skb->protocol ==
> > htons(ETH_P_IPV6)'.  For the current code, the compiler will probably
> > generate a run-time byte-swap for little-endian systems.

True.  Perhaps this would be better written as:

	if (left) {
		if (left < num ||
		    (ip->ip_summed == CHECKSUM_PARTIAL &&
		     skb->protocol == htons(ETH_P_IPV6))) {

			etc...