From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hangbin Liu <liuhangbin@gmail.com>
Subject: Re: [PATCH net] ipv6: no need to return rt->dst.error if it is not
 null entry.
Date: Wed, 26 Jul 2017 17:18:53 +0800
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Cc: network dev <netdev@vger.kernel.org>,
        Roopa Prabhu <roopa@cumulusnetworks.com>,
        David Ahern <dsahern@gmail.com>
To: Cong Wang <xiyou.wangcong@gmail.com>
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On Tue, Jul 25, 2017 at 10:49:05AM -0700, Cong Wang wrote:
> On Mon, Jul 24, 2017 at 5:08 PM, Hangbin Liu <liuhangbin@gmail.com> wrote:
> > But what we want in inet6_rtm_getroute() and rt6_dump_route() is to
> > get/dump the route info. So we should get the info even it's unreachable or
> > prohibit.
> 
> If you want to dump prohibit/blackhole entry, then you have to check
> for null_entry, and rt->dst.error check is still needed because we

I could not reproduce the NULL rt6i_idev issue after you route init fix, So
I think it's also safe to dump null_entry now. There is a v3 patch. After
the patch, we could dump unreachable route info like:

+ ip netns exec client ip -6 route get 2003::1
unreachable 2003::1 dev lo table unspec proto kernel metric 4294967295 error -101

> could return error on other normal entries too, IOW, your v2 is correct
> if dumping prohibit/blackhole is expected.

Would you hlep review the v3 patch? I prepare not touch the check in
function rt6_dump_route() now.

Thanks
Hangbin