Re: linux-next: Tree for Aug 6 [ wireless | iwlwifi | mac80211 ? ]

[Johannes Berg <johannes@sipsolutions.net>]

On Tue, 2013-08-06 at 23:45 +0200, Johannes Berg wrote:

> I think skb->protocol is probably getting set up wrong, and just putting
> back the last two lines
> 
>         skb->protocol = proto;
>         skb->dev = dev;
> 
> is probably sufficient to fix wifi. If skb->protocol isn't set to
> ETH_P_PAE, then we'd drop the packet in the wifi stack - might be worth
> printing out what it's set to at the point where the skb->protocol
> assignment above was removed.
> 
> I'm trying to wrap my head around all this right now but I don't yet see
> how the code after the patch would not get skb->protocol correct.

Actually, I think that's not it, but the code now behaves totally
differently?

Say this is the frame data with two points marked:

(1)                   (2)
 | dst | src | ethtype | ... |

As I understand it (in my admittedly rather tired state), previously we
had

skb_network_header() == (1)
skb_mac_header()     == (1)
skb->data            == (1)

After calling eth_type_trans(), we get

skb_network_header() == (1)
skb_mac_header()     == (1)
skb->data            == (2)

I think? Maybe I'm totally confused though.

johannes