Re: [PATCH net-next 1/4] selftests: forwarding: Test redirecting gre or ipip packets to Ethernet

From: Guillaume Nault <gnault@redhat.com>
To: David Ahern <dsahern@gmail.com>
Cc: Ido Schimmel <idosch@idosch.org>,
	David Miller <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	netdev@vger.kernel.org, Shuah Khan <shuah@kernel.org>,
	linux-kselftest@vger.kernel.org
Subject: Re: [PATCH net-next 1/4] selftests: forwarding: Test redirecting gre or ipip packets to Ethernet
Date: Fri, 9 Jul 2021 18:21:23 +0200	[thread overview]
Message-ID: <20210709162123.GB19430@pc-23.home> (raw)
In-Reply-To: <391b6a56-b7e0-867c-617e-a05afec50b24@gmail.com>

On Wed, Jul 07, 2021 at 07:50:38PM -0600, David Ahern wrote:
> On 7/6/21 1:02 PM, Guillaume Nault wrote:
> > --- a/drivers/net/vxlan.c
> > +++ b/drivers/net/vxlan.c
> > @@ -3767,8 +3767,7 @@ static int vxlan_config_validate(struct net *src_net, struct vxlan_config *conf,
> >  		    (conf->flags & (VXLAN_F_RCV_FLAGS | VXLAN_F_IPV6)))
> >  			continue;
> >  
> > -		if ((conf->flags & VXLAN_F_IPV6_LINKLOCAL) &&
> > -		    tmp->cfg.remote_ifindex != conf->remote_ifindex)
> > +		if (tmp->cfg.remote_ifindex != conf->remote_ifindex)
> >  			continue;
> >  
> >  		NL_SET_ERR_MSG(extack,
> 
> Looking at the vxlan driver and that restriction is unnecessary. While
> IPv6 LLA requires a device index, allowing separate LINK attributes is a
> legit use case - as VRF shows.

I believe there's more to do than just my quick hack patch. At least
vxlan_vs_find_vni() probably needs to be modified too. At which point
VXLAN_F_IPV6_LINKLOCAL would become essentially unused and should be
removed.

> Do you want to send a formal patch to fix this one since you have it
> diagnosed?

I'll work on that after net-next reopens. I might try to make bareudp
compatible with VRF too, if time allows. If I get at least VXLAN and
bareudp to work in a multi-VRF setup, then I'll rebase the selftests on
the VRF infrastructure (and just remove the tests for tunnels still
incompatible with this setup).