From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cong Wang <xiyou.wangcong@gmail.com>
Subject: Re: Latest net-next kernel 4.19.0+
Date: Thu, 8 Nov 2018 10:35:37 -0800
Message-ID: <CAM_iQpXKBxit9obeF3RiCttEULTjU_L1D3jHV2=sLqwsvWYK8w@mail.gmail.com>
References: <59d5657c-ea0a-7b64-d5ff-5b55eb4fcccf@itcare.pl>
 <ec5c3923-a268-aa2c-fea1-350f8bce65c2@itcare.pl> <CAM_iQpWWZqur_dLC_eM7iX7BFDncrYFSXHohwxCt2xMaAjRpMQ@mail.gmail.com>
 <1e954663-ed05-4f33-4384-db880844f9d1@gmail.com> <db6848dc-cf1b-0989-570c-af5bdd1a7bd1@gmail.com>
 <CAG76SjY7fnFdgamBELATyO8NGnyNFYiX33SgLE6-q=eoBM8jKg@mail.gmail.com>
 <68f25a28-b79e-d3ae-6eef-50c354ad63ae@gmail.com> <b0a36d1f-5518-392c-d731-1ec66ec48f92@itcare.pl>
 <76dfbbda-d7f1-b13a-5921-c12c3b0f8e3e@gmail.com> <CAM_iQpUKTh51maAzht8M3LuJAYDRMRnsGn_+Db0rGG-scW2SnA@mail.gmail.com>
 <7f19ab59f1bbfe74cf3d056ccd9adf556cd09f60.camel@mellanox.com>
 <CAM_iQpXLNyHG1qo8y-53ZRwyeL30v0JANFWfK=2b58L8vpQMbw@mail.gmail.com> <f4759eda-8a47-3114-f944-69b9ff6c2e87@itcare.pl>
Mime-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Cc: Saeed Mahameed <saeedm@mellanox.com>,
        Eric Dumazet <eric.dumazet@gmail.com>,
        Linux Kernel Network Developers <netdev@vger.kernel.org>,
        Dimitris Michailidis <dmichail@google.com>
To: =?UTF-8?Q?Pawe=C5=82_Staszewski?= <pstaszewski@itcare.pl>
Return-path: <netdev-owner@vger.kernel.org>
Received: from mail-pg1-f195.google.com ([209.85.215.195]:44511 "EHLO
        mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1727196AbeKIEMg (ORCPT
        <rfc822;netdev@vger.kernel.org>); Thu, 8 Nov 2018 23:12:36 -0500
Received: by mail-pg1-f195.google.com with SMTP id w3-v6so9204845pgs.11
        for <netdev@vger.kernel.org>; Thu, 08 Nov 2018 10:35:49 -0800 (PST)
In-Reply-To: <f4759eda-8a47-3114-f944-69b9ff6c2e87@itcare.pl>
Sender: netdev-owner@vger.kernel.org
List-ID: <netdev.vger.kernel.org>

On Thu, Nov 1, 2018 at 3:59 PM Pawe=C5=82 Staszewski <pstaszewski@itcare.pl=
> wrote:
>
>
>
> W dniu 31.10.2018 o 22:17, Cong Wang pisze:
> > On Wed, Oct 31, 2018 at 2:05 PM Saeed Mahameed <saeedm@mellanox.com> wr=
ote:
> >> Cong, How often does this happen ? can you some how verify if the
> >> problematic packet has extra end padding after the ip payload ?
> > For us, we need 10+ hours to get one warning. This is also
> > why we never capture the packet that causes this warning.
> >
> >
> >> It would be cool if we had a feature in kernel to store such SKB in
> >> memory when such issue occurs, and let the user dump it later (via
> >> tcpdump) and send the dump to the vendor for debug so we could just
> >> replay and see what happens.
> >>
> > Yeah, the warning kinda sucks, it tells almost nothing, the SKB
> > should be dumped up on this warning.
> >
>
> So another vlan and same hw csum - this time this vlan have less traffic
> so i catch traffic with tcpdump
> Nov  1 23:46:22 kernel: vlan2805: hw csum failure
> but the problem is there is about 1986 frames in that second
> Will tcpdump output helps ?

Looks like you don't have any IP fragments.

Do you try Eric's debugging patch? Does it make a difference?

Also, if doable, can you try to remove vlan from your setup to see if
the warning will be gone?

Thanks!