Re: [PATCH net v2] net: Avoid calling WARN_ON() on -ENOMEM in netif_change_net_namespace()

[Eric Dumazet]

On Fri, Apr 4, 2025 at 9:29 AM Ivan Abramov <i.abramov@xxxxxxxxxxxxxxxxx> wrote:
>
> On Thu, 3 Apr 2025 11:05:31 -0700, Stanislav Fomichev wrote:
> > On 04/03, Ivan Abramov wrote:
> >> It's pointless to call WARN_ON() in case of an allocation failure in
> >> device_rename(), since it only leads to useless splats caused by deliberate
> >> fault injections, so avoid it.
>
> > What if this happens in a non-fault injection environment? Suppose
> > the user shows up and says that he's having an issue with device
> > changing its name after netns change. There will be no way to diagnose
> > it, right?
>
> Failure to allocate a few hundred bytes in kstrdup doesn't seem
> practically possible and happens only in fault injection scenarios. Other
> types of failures in device_rename will still trigger WARN_ON.

If you want to fix this, fix it properly.

Do not paper around the issue by silencing a warning.