Re: [PATCH net-next] hyperv: Add handler for RNDIS_STATUS_NETWORK_CHANGE event

[Vitaly Kuznetsov <vkuznets@redhat.com>]

Haiyang Zhang <haiyangz@microsoft.com> writes:

>> -----Original Message-----
>> From: Richard Weinberger [mailto:richard.weinberger@gmail.com]
>> Sent: Tuesday, October 27, 2015 6:36 PM
>> To: David Miller <davem@davemloft.net>
>> Cc: Haiyang Zhang <haiyangz@microsoft.com>; olaf@aepfle.de; Greg Kroah-
>> Hartman <greg@kroah.com>; netdev@vger.kernel.org; jasowang@redhat.com;
>> driverdev-devel@linuxdriverproject.org; LKML <linux-
>> kernel@vger.kernel.org>
>> Subject: Re: [PATCH net-next] hyperv: Add handler for
>> RNDIS_STATUS_NETWORK_CHANGE event
>> 
>> On Mon, Jun 23, 2014 at 10:10 PM, David Miller <davem@davemloft.net>
>> wrote:
>> > From: Haiyang Zhang <haiyangz@microsoft.com>
>> > Date: Mon, 23 Jun 2014 16:09:59 +0000
>> >
>> >> So, what's the equivalent or similar command to "network restart" on
>> SLES12? Could
>> >> you update the command line for the usermodehelper when porting this
>> patch to SLES
>> >> 12?
>> >
>> > No, you are not going to keep the usermodehelper invocation in your
>> driver
>> > please remove it.  It is absolutely inappropriate, and I strictly do
>> not want
>> > to keep it in there because other people will copy it and then we'll
>> have a
>> > real mess on our hands.
>> 
>> Sorry for digging up this old thread.
>> While talking with some guys about usermodehelper abuses I came across
>> this gem.
>> Mainline still contains that "/etc/init.d/network restart" code.
>> Haiyang, care to cleanup?
>
> Hi Richard and others,
>
> Thanks for the reminder. I will clean up the usermode helper.
>
> Do you have suggestions of trigger DHCP refresh from kernel mode? Any 
> sample code in the existing kernel code?
>

I think it's wrong to call dhcp refresh from kernel. What happens when
we reconnect normal hardware adapter to another network? Link goes down
and then up and userspace is supposed to react accordingly. I think we
should emulate something similar for RNDIS_STATUS_NETWORK_CHANGE.

-- 
  Vitaly