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.com \
--cc=herbert@gondor.apana.org.au \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.