From: Jakub Kicinski <kuba@kernel.org>
To: Chris Arges <carges@cloudflare.com>
Cc: Weiming Shi <bestswngs@gmail.com>,
Eric Dumazet <edumazet@google.com>,
Paolo Abeni <pabeni@redhat.com>,
netdev@vger.kernel.org, kernel-team@cloudflare.com,
jgriege@cloudflare.com
Subject: Re: [REGRESSION] net: add xmit recursion limit to tunnel xmit functions
Date: Wed, 1 Apr 2026 17:38:43 -0700 [thread overview]
Message-ID: <20260401173843.7a2bb607@kernel.org> (raw)
In-Reply-To: <acwp_cVAflwTQCBh@20HS2G4>
On Tue, 31 Mar 2026 15:09:33 -0500 Chris Arges wrote:
> Commit 6f1a9140ecda ("net: add xmit recursion limit to tunnel xmit functions")
> introduces a regression in our systems using legitimate multi-level tunnel
> encapsulation stacks. Our testing was with stable 6.12.y and 6.18.y where this
> patch was backported.
>
> One of the usecases we have are packets being sent to a GRE device, then
> MPLS/LWT route, then IPIP device, then SIT/FOU device. What we observed is that
> packets are getting dropped at the last device and we get the message "Dead
> loop on virtual device" sent from the iptunnel_xmit function.
Last device meaning limit of 5 would have worked for you?
I don't think there was any hard math behind the 4 so ++
on the limit may be simplest, but I defer to Paolo..
next prev parent reply other threads:[~2026-04-02 0:38 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-03-31 20:09 [REGRESSION] net: add xmit recursion limit to tunnel xmit functions Chris Arges
2026-04-02 0:38 ` Jakub Kicinski [this message]
2026-04-02 9:31 ` Paolo Abeni
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=20260401173843.7a2bb607@kernel.org \
--to=kuba@kernel.org \
--cc=bestswngs@gmail.com \
--cc=carges@cloudflare.com \
--cc=edumazet@google.com \
--cc=jgriege@cloudflare.com \
--cc=kernel-team@cloudflare.com \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
/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.