Subject: Re: [PATCH iproute2] vxlan: Add support for modifying vxlan device attributes

From: Stephen Hemminger <[email-masked]>
Date: Thu, 4 May 2017 17:07:43 -0700

On Thu,  4 May 2017 14:46:34 -0700
Girish Moodalbail <[email-masked]> wrote:

> Ability to change vxlan device attributes was added to kernel through
> commit 8bcdc4f3a20b ("vxlan: add changelink support"), however one
> cannot do the same through ip(8) command.  Changing the allowed vxlan
> device attributes using 'ip link set dev <vxlan_name> type vxlan
> <allowed_attributes>' currently fails with 'operation not supported'
> error.  This failure is due to the incorrect rtnetlink message
> construction for the 'ip link set' operation.
> 
> The vxlan_parse_opt() callback function is called for parsing options
> for both 'ip link add' and 'ip link set'. For the 'add' case, we pass
> down default values for those attributes that were not provided as CLI
> options. However, for the 'set' case we should be only passing down the
> explicitly provided attributes and not any other (default) attributes.
> 
> Signed-off-by: Girish Moodalbail <[email-masked]>
> ---

All these foo_set variables are ugly. This looks almost like machine
generated code. It doesn't read well.