From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <dsa@cumulusnetworks.com>
Subject: Re: [PATCH net-next V3 2/2] rtnl: Add support for netdev event
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Date: Tue, 2 May 2017 15:57:48 -0600
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Cc: Vladislav Yasevich <vyasevich@gmail.com>, netdev@vger.kernel.org,
        roopa <roopa@cumulusnetworks.com>
To: vyasevic@redhat.com, Jiri Pirko <jiri@resnulli.us>
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On 5/1/17 7:35 AM, Vlad Yasevich wrote:
> So, it looks like the notifier might be there to account for the ioctl/sysfs
> interfaces.

hmmm... I guess we have to leave it then.

> 
> Additionally, the message is not generated from do_setlink() if the devices is
> down, so notifier accounts for that as well.
> 
> I guess, basic question is whether data carried in NETDEV_CHANGEINFODATA is useful
> to user space?  If yes (I can possibly see some managements apps that might be interested
> in it), then we shouldn't just remove it.  Possible solutions to eliminate duplicates
> would be to move the notifier call into non-rtnl code paths...
> 
> Also, may be netdev_state_change() should call rtmsg_ifinfo() unconditionally?

Link up will generate a message, so userspace gets notified at some point.