HWSIM_ATTR_COOKIE
if (nla_put_u64_64bit(skb, HWSIM_ATTR_COOKIE, cookie, HWSIM_ATTR_PAD))
!info->attrs[HWSIM_ATTR_COOKIE] ||
ret_skb_cookie = nla_get_u64(info->attrs[HWSIM_ATTR_COOKIE]);
[HWSIM_ATTR_COOKIE] = { .type = NLA_U64 },