Subject: Re: [PATCH net-next v11 0/3] netdevsim: link and forward skbs between ports

From: Jakub Kicinski <[email-masked]>
Date: Fri, 16 Feb 2024 06:44:13 -0800

On Fri, 16 Feb 2024 11:38:17 +0100 Paolo Abeni wrote:
> On Thu, 2024-02-15 at 11:43 -0800, David Wei wrote:
> > This patchset adds the ability to link two netdevsim ports together and
> > forward skbs between them, similar to veth. The goal is to use netdevsim
> > for testing features e.g. zero copy Rx using io_uring.
> > 
> > This feature was tested locally on QEMU, and a selftest is included.  
> 
> this apparently causes rtnetlink.sh self-tests failures:
> 
> https://netdev.bots.linux.dev/flakes.html?tn-needle=rtnetlink-sh
> 
> example failure:
> 
> https://netdev-3.bots.linux.dev/vmksft-net/results/467721/18-rtnetlink-sh/stdout
> 
> the ipsec_offload test (using netdevsim) fails.
> 
> @Jakub: it looks like the rtnetlink.sh test is currently ignored by
> patchwork, skimming over the recent failures they are roughly
> correlated to this series submission: the test looks otherwise
> reasonably stable to me.

Wow, great detective work! This is what the diff says:

#     1c1
# < SA count=2 tx=0
# ---
# > SA count=2 tx=3

I'm guessing that because we clear IFF_NOARP and ipsec code doesn't
connect any peer it can't transmit? Any suggestions how to fix it?
Insert a neigh entry manually?