Re: [PATCH net-next v5 01/22] rtnetlink: provide permanent hardware address in RTM_NEWLINK

From: Michal Kubecek
Date: Tue Mar 26 2019 - 06:31:25 EST


On Tue, Mar 26, 2019 at 11:08:36AM +0100, Jiri Pirko wrote:
>
> I don't think we should put permaddr if driver did not set it. 2
> solutions:
> 1) provide a helper that driver will use to set the perm_addr. This
> helper sets a "valid bit". Then you only put IFLA_PERM_ADDRESS
> in case the "valid bit" is set.
> 2) Assuming that no driver would set permaddr to all zeroes,
> don't put IFLA_PERM_ADDRESS in case permadd is all zeroes.

I already replied to similar suggestion in v4 discussion:

http://patchwork.ozlabs.org/patch/1060164/#2117512

But I don't have really strong opinion about this. The problem with not
being able to distinguish between "no/unknown permanent address" and
"old kernel not providing the information" is going to become less
important over time.

Michal