Hi guys! Yes, that's exactly it! Thank you very much, so now I know what is happening 😊.
Thanks again for your help! BR, Jan Szewczyk -----Original Message----- From: David Ahern <dsah...@gmail.com> Sent: Wednesday, July 10, 2019 21:13 To: Stefano Brivio <sbri...@redhat.com>; Jan Szewczyk <jan.szewc...@ericsson.com> Cc: da...@davemloft.net; netdev@vger.kernel.org; Wei Wang <wei...@google.com>; Martin KaFai Lau <ka...@fb.com>; Eric Dumazet <eduma...@google.com> Subject: Re: Question about linux kernel commit: "net/ipv6: move metrics from dst to rt6_info" On 7/10/19 1:09 PM, Stefano Brivio wrote: > Jan, > > On Wed, 10 Jul 2019 12:59:41 +0000 > Jan Szewczyk <jan.szewc...@ericsson.com> wrote: > >> Hi! >> I digged up a little further and maybe it's not a problem with MTU >> itself. I checked every entry I get from RTM_GETROUTE netlink message >> and after triggering "too big packet" by pinging ipv6address I get >> exactly the same messages on 4.12 and 4.18, except that the one with >> that pinged ipv6address is missing on 4.18 at all. What is weird - >> it's visible when running "ip route get to ipv6address". Do you know >> why there is a mismatch there? > > If I understand you correctly, an implementation equivalent to 'ip -6 > route list show' (using the NLM_F_DUMP flag) won't show the so-called > route exception, while 'ip -6 route get' shows it. > > If that's the case: that was broken by commit 2b760fcf5cfb ("ipv6: > hook up exception table to store dst cache") that landed in 4.15, and > fixed by net-next commit 1e47b4837f3b ("ipv6: Dump route exceptions if > requested"). For more details, see the log of this commit itself. > ah, good point. My mind locked on RTM_GETROUTE as a specific route request not a dump.