Subject: Re: [PATCH iproute2] ip route: get: only set RTM_F_LOOKUP_TABLE flag for IPv4

From: David Ahern <[email-masked]>
Date: Mon, 14 Jan 2019 09:29:51 -0700

On 1/14/19 9:05 AM, Stephen Hemminger wrote:
> On Sat, 12 Jan 2019 12:54:06 -0800
> Jakub Kicinski <[email-masked]> wrote:
> 
>> Kernel ignores the RTM_F_LOOKUP_TABLE flag for all families
>> but IPv4.  Don't set it, otherwise it may fall foul of
>> strict checking policies.
>>
>> Signed-off-by: Jakub Kicinski <[email-masked]>
> 
> Doing the right thing is a good idea, but really I can't see
> the point of doing this. The kernel will always have to accept
> requests from older versions of iproute2 (it can never be stricter)
> because of ABI compatibility. So unless you can make a stronger
> case for this; no not applying it.
> 

iproute2 is often used as a reference model for features. Making
iproute2 correct is the right thing to do regardless of whether what the
kernel accepts.

Current master branch is the first iproute2 to use the strict checking,
and its first release with strict checking should have as many of these
little one offs as possible fixed.