public inbox for netdev@vger.kernel.org 
 help / color / mirror / Atom feed
From: Hannes Frederic Sowa <hannes@stressinduktion•org>
To: RongQing Li <roy.qing.li@gmail•com>
Cc: Gao feng <gaofeng@cn•fujitsu.com>, netdev@vger•kernel.org
Subject: Re: [PATCH] ipv6: clear RTF_EXPIRES when call ip6_rt_copy
Date: Wed, 18 Dec 2013 07:20:00 +0100	[thread overview]
Message-ID: <20131218062000.GC27460@order.stressinduktion.org> (raw)
In-Reply-To: <CAJFZqHxB8PscqXnX9oxpHf8zFyW1hyCZVZTn_=DoKebN3X2ZGA@mail.gmail.com>

On Wed, Dec 18, 2013 at 10:21:12AM +0800, RongQing Li wrote:
> On Wed, Dec 18, 2013 at 10:09 AM, Gao feng <gaofeng@cn•fujitsu.com> wrote:
> > On 12/18/2013 09:58 AM, RongQing Li wrote:
> >> On Wed, Dec 18, 2013 at 8:48 AM, Gao feng <gaofeng@cn•fujitsu.com> wrote:
> >>> On 12/17/2013 09:48 PM, Hannes Frederic Sowa wrote:
> >>>> On Tue, Dec 17, 2013 at 03:46:24PM +0800, Gao feng wrote:
> >>>>> The from of new cloned rt should not be set if it's impossible for the ort
> >>>>> to be expired.
> >>>>
> >>>> Actually, why do you think so? What could go wrong?
> >>>>
> >>>
> >>> I just don't want rt6_check_expired to check some impossible expired routes.
> >>>
> >>
> >> What is wrong if we set from for new cloned rt by checking if ort has
> >> RTF_EXPIRES flag?
> >
> >
> > The RTF_EXPIRES flag may be changed by router advertisment package,
> > the ort may become expired after you hadn't set from for new cloned rt.
> >
> > we should set from even this kind of ort doesn't have RTF_EXPIRES flag.
> 
> 
> Thanks;
> 
> Do we want to set from only from RA route?  if so,  we should check
> ort with RTF_ADDRCONF|RTF_DEFAULT, or RTF_ADDRCONF | RTF_ROUTEINFO,

Nope, as I said, also prefix routes which did get installed by hand locally
can have an expiration. I don't see any flag combination which ensure a
potential from does never expire. IMHO we should always from.

Also, in case we overwrite a route and the route is already in there, we reset
the expiry values: search for rt6_set_expires in fib6_add_rt2node.

We had the same problem with ECMP routes. We only wanted to add non-expiration
routes but we could not find a combination which did ensure that. In the end
we now also add non-expiration routes to an ecmp set (see commit
307f2fb95e9b96).

Greetings,

  Hannes

  reply	other threads:[~2013-12-18  6:20 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-12-16  8:31 [PATCH] ipv6: clear RTF_EXPIRES when call ip6_rt_copy roy.qing.li
2013-12-16 13:47 ` Eric Dumazet
2013-12-17  3:25 ` Gao feng
2013-12-17  3:32   ` RongQing Li
2013-12-17  5:57     ` Gao feng
2013-12-17  6:42       ` RongQing Li
2013-12-17  7:02         ` Hannes Frederic Sowa
2013-12-17  7:46           ` Gao feng
2013-12-17  8:30             ` Hannes Frederic Sowa
2013-12-17  9:23               ` Gao feng
2013-12-17 13:48             ` Hannes Frederic Sowa
2013-12-18  0:48               ` Gao feng
2013-12-18  1:58                 ` RongQing Li
2013-12-18  2:09                   ` Gao feng
2013-12-18  2:21                     ` RongQing Li
2013-12-18  6:20                       ` Hannes Frederic Sowa [this message]
2013-12-18  8:40                         ` Gao feng
2013-12-19  0:37                           ` Hannes Frederic Sowa
2013-12-19  0:47                             ` RongQing Li
2013-12-19  4:40                             ` [PATCH v2] ipv6: always set the new created dst's from in ip6_rt_copy roy.qing.li
2013-12-19 12:43                               ` Hannes Frederic Sowa
2013-12-19 23:36                               ` David Miller
2013-12-18  7:59                 ` [PATCH] ipv6: clear RTF_EXPIRES when call ip6_rt_copy Hannes Frederic Sowa

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20131218062000.GC27460@order.stressinduktion.org \
    --to=hannes@stressinduktion$(echo .)org \
    --cc=gaofeng@cn$(echo .)fujitsu.com \
    --cc=netdev@vger$(echo .)kernel.org \
    --cc=roy.qing.li@gmail$(echo .)com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox