Subject: Re: [PATCH net-next v5 08/22] ethtool: support for netlink notifications

From: Andrew Lunn <[email-masked]>
Date: Wed, 27 Mar 2019 10:51:48 +0100

On Wed, Mar 27, 2019 at 10:38:43AM +0100, Jiri Pirko wrote:
> Tue, Mar 26, 2019 at 07:17:20PM CET, [email-masked] wrote:
> >On Tue, Mar 26, 2019 at 05:34:00PM +0100, Jiri Pirko wrote:
> >> Mon, Mar 25, 2019 at 06:08:18PM CET, [email-masked] wrote:
> >> >+void ethtool_notify(struct net_device *dev, struct netlink_ext_ack *extack,
> >> >+		    unsigned int cmd, u32 req_mask, const void *data)
> >> >+{
> >> >+	if (unlikely(!ethnl_ok))
> >> 
> >> Why do you need this?
> >
> >If genetlink family registration fails, ethtool_notify() can be still
> >called from other code (e.g. the ethtool ioctl interface). In such case,
> >better bail out right away than fail somewhere later (probably after
> >preparing the message which can't be sent anyway).
> 
> Again, haven't seen this in any other gen netlink implementation. Why do
> they not need it?

Hi Jiri

All other gen netlink kill the machine dead if they cannot register
the socket.

    Andrew