Subject: Re: [PATCH net-next v3 4/5] net/tc: introduce TC_ACT_REINJECT.

From: Jiri Pirko <[email-masked]>
Date: Wed, 25 Jul 2018 14:59:51 +0200

Wed, Jul 25, 2018 at 02:16:12PM CEST, [email-masked] wrote:

[...]

>> diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
>> index 2081e4219f81..36ccfe2a303a 100644
>> --- a/include/net/pkt_cls.h
>> +++ b/include/net/pkt_cls.h
>> @@ -7,6 +7,9 @@
>>   #include <net/sch_generic.h>
>>   #include <net/act_api.h>
>> +/* TC action not accessible from user space */
>> +#define TC_ACT_REINJECT		(TC_ACT_VALUE_MAX + 1)
>
>Lets say in the future we add a new opcode.
>Will old kernel, new iproute2 (new value) work?

This is safe. See patch #2.