On Wed, Jun 6, 2018 at 2:11 PM, David Miller <da...@davemloft.net> wrote: > From: Alexander Aring <ar...@mojatatu.com> > Date: Wed, 6 Jun 2018 14:09:20 -0400 > >> okay, then you want to have this patch for net-next? As an optimization? >> >> Of course, when it's open again. > > Like you, I have questions about where this adjustment is applied and > why. So I'm not sure yet. > > For example, only IPV6 really takes it into consideration and as you > saw only really for the fragmentation path and not the normal output > path. > > This needs more consideration and investigation.
This is the unconditional skb_put in ieee802154_tx. In many cases there is some tailroom due to SKB_DATA_ALIGN in __alloc_skb, so it may take a specific case to not have even 2 bytes of tailroom available.
