Re: [PATCH v1] vxcan: Support per-netns device unregistration.

On Mon, Jul 13, 2026 at 9:57 AM Oliver Hartkopp <[email protected]> wrote:
> On 12.07.26 23:34, [email protected] wrote:
> > Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
> > - [Low] The patch calls the undefined function `unregister_netdevice_queue_net()`, resulting in a compilation error.
> > --
> >
> > --- Patch [1]: [PATCH v1] vxcan: Support per-netns device unregistration. ---
> > commit 882fcd31630d9ce6b0a57cc99738c2ad0579763f
> > Author: Kuniyuki Iwashima <[email protected]>
> >
> > vxcan: Support per-netns device unregistration.
> >
> > This commit updates vxcan_dellink() to unregister local and peer devices
> > safely across different namespaces by using xchg(). The change aims to
> > prevent double-queuing of device destruction when RTNL is removed.
> >
> >> diff --git a/drivers/net/can/vxcan.c b/drivers/net/can/vxcan.c
> >> --- a/drivers/net/can/vxcan.c
> >> +++ b/drivers/net/can/vxcan.c
> >
> > [ ... ]
> >
> >> @@ -281,24 +284,25 @@ static int vxcan_newlink(struct net_device *dev,
> >>
> >>   static void vxcan_dellink(struct net_device *dev, struct list_head *head)
> >>   {
> >
> > [ ... ]
> >
> >>      unregister_netdevice_queue(dev, head);
> >>
> >> -    if (peer) {
> >> -            priv = netdev_priv(peer);
> >> -            RCU_INIT_POINTER(priv->peer, NULL);
> >> -            unregister_netdevice_queue(peer, head);
> >> -    }
> >> +    priv = netdev_priv(peer);
> >> +    dev = unrcu_pointer(xchg(&priv->peer, NULL));
> >> +    if (dev)
> >> +            unregister_netdevice_queue_net(dev_net(dev), peer, head);
> >
> > [Severity: Low]
> > Is this missing a prerequisite patch? It appears that
> > unregister_netdevice_queue_net() is not defined anywhere in the kernel
> > tree, which leads to a compilation error when building vxcan.c.
>
> The referenced veth.c patch was applied to net-next:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=d7fda2c776b2a969b9d78c5ad00e30824df43add
>
> where also unregister_netdevice_queue_net() exists.
>
> So this is a net-next resp. can-next patch.

Yes, I meant this is for can-next, but I was not sure how frequently
the tree is synced against net-next and what's the best approach here.