From: Steffen Klassert <steffen.klassert@secunet•com>
To: Herbert Xu <herbert@gondor•apana.org.au>
Cc: <netdev@vger•kernel.org>
Subject: Re: IPv6 xfrm GSO fragmentation bug
Date: Mon, 31 Aug 2015 09:19:16 +0200 [thread overview]
Message-ID: <20150831071916.GG25499@secunet.com> (raw)
In-Reply-To: <20150830082432.GA25588@gondor.apana.org.au>
On Sun, Aug 30, 2015 at 04:24:32PM +0800, Herbert Xu wrote:
> Hi Steffen:
>
> I received a bug report regarding poor IPComp performance over
> IPv6:
>
> https://bugzilla.redhat.com/show_bug.cgi?id=1257952
>
> It appears to have been caused by
>
> commit dd767856a36e00b631d65ebc4bb81b19915532d6
> Author: Steffen Klassert <steffen.klassert@secunet•com>
> Date: Tue Oct 11 01:44:30 2011 +0000
>
> xfrm6: Don't call icmpv6_send on local error
>
> which addded an MTU check without a GSO override.
>
> Fixing it obviously isn't difficult, but I am wondering why I
> can't find a corresponding patch for IPv4. Do we need that check
> to be present in xfrm6_output at all? If we do why isn't it needed
> for IPv4 as well?
As far as I remember, this was to catch local message size
errors before __xfrm6_output calls ip6_fragment which would
use icmpv6_send for the error notification. IPv4 does not do
fragmentation in the xfrm4_output functions, so this mtu
check was not needed there.
I think just adding the gso checks should be fine.
next prev parent reply other threads:[~2015-08-31 7:19 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-08-30 8:24 IPv6 xfrm GSO fragmentation bug Herbert Xu
2015-08-31 7:19 ` Steffen Klassert [this message]
2015-08-31 7:35 ` Herbert Xu
2015-09-04 5:21 ` Herbert Xu
2015-09-07 10:00 ` Steffen Klassert
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=20150831071916.GG25499@secunet.com \
--to=steffen.klassert@secunet$(echo .)com \
--cc=herbert@gondor$(echo .)apana.org.au \
--cc=netdev@vger$(echo .)kernel.org \
/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