On (09/23/16 10:38), Alexander Duyck wrote: > > So basically what I was thinking is we do something like reserving > NET_IP_ALIGN and continue writing headers to skb->data, but we force > the tracking for the inner headers into frag[0] so that we can keep > the inner headers aligned without messing up the alignment for outer > headers. In theory the inner offset and all that would still be > functional but might need a few tweaks. You could probably even use > the skb->encapsulation bit to indicate you are doing this. You could > almost think of it as us doing something like the inverse of > pskb_pull_tail. The general idea here is we want to actually leave > the data in skb->data, but just reference it from frag[0] so that we > don't accidentally pull in the 2 byte padding for alignment when > transmitting the frame.
yes, I think something along this line could do the trick.. I tried hacking it a bit today for vxlan, and it could be extended for all these encaps protocols. Let me fix/test this more next week, maybe we can discuss in Tokyo. --Sowmini