From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <dsahern@gmail.com>
Subject: Re: [patch net-next RFC 1/9] net_sch: red: Add offload ability to RED
 qdisc
Date: Mon, 30 Oct 2017 13:24:20 -0600
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On 10/30/17 7:54 AM, Nogah Frankel wrote:
>>> diff --git a/include/uapi/linux/pkt_sched.h b/include/uapi/linux/pkt_sched.h
>>> index 0e88cc2..743c42a 100644
>>> --- a/include/uapi/linux/pkt_sched.h
>>> +++ b/include/uapi/linux/pkt_sched.h
>>> @@ -255,6 +255,7 @@ struct tc_red_qopt {
>>>  #define TC_RED_ECN		1
>>>  #define TC_RED_HARDDROP		2
>>>  #define TC_RED_ADAPTATIVE	4
>>> +#define TC_RED_OFFLOADED	8
>>>  };
>>>
>>>  struct tc_red_xstats {
>>
>> What keeps a user from setting this flag in the tc_red_qopt it
>> passes into the a change operation?
> 
> Nothing keeps the user from doing it, but it has no effect.
> The decision to offload is the driver's only.
> It is basically a read-only flag.
> 

If it is read-only, then attempts to set it from userspace should cause
the command to fail.