Re: [PATCH v4 net-next] net:sched: add action inheritdsfield to skbedit

On 06/19/2018 08:01 AM, Jamal Hadi Salim wrote:

Per my previous comments, why do we need the
TCA_SKBEDIT_FLAGS TLV? Isnt SKBEDIT_F_INHERITDSFIELD
sufficient? i.e in tcf_skbedit_init() check for
d->flags&SKBEDIT_F_INHERITDSFIELD then set skb->priority
and flags|=SKBEDIT_F_INHERITDSFIELD

    Notice that, different from skbmod, there's no field parm->flags in 
skbedit. Skbedit infers the flags in d->flags from the presence of the 
parameters of each of its actions. But SKBEDIT_F_INHERITDSFIELD has no 
parameter and adding field parm->flags breaks backward compatibility 
with user space as pointed out by Marcelo Ricardo Leitner. Our solution 
was to add TCA_SKBEDIT_FLAGS, so SKBEDIT_F_INHERITDSFIELD and future 
flag-only actions can be added.

[ ]'s
Michel Machado